HOW DOES COPYRIGHT AFFECT SCIENCE?
EVIDENCE FROM THE WORLD WAR II BOOK REPUBLICATION
PROGRAM*
BARBARA BIASI, STANFORD, AND
PETRA MOSER, STANFORD AND NBER
APRIL 13, 2015
EARLY AND PRELIMINARY DRAFT
COMMENTS MUCH APPRECIATED – THANKS!
This paper examines the effects of copyright violations under the World War I Book
Republication Program (BRP) on the production of new scientific knowledge. Under the
BRP, US publishers could print legal copies of books with German-owned copyrights. We
find that citations to BRP books increased dramatically after 1942, whereas citations to Swiss
books– which could not be copied due to Switzerland’s neutrality – remained low.
Comparisons across research fields indicate that citations increased most for fields in which
knowledge production was more dependent on human capital (mathematics), and less for
fields more dependent on physical capital (chemistry). Notably, a 10-percent reduction in the
price of a book was associated with an 90 percent increase in citations across all books and
264 percent in mathematics.
KEYWORDS: SCIENCE, KNOWLEDGE CREATION, HUMAN CAPITAL, CUMULATIVE INVENTION,
COPYRIGHT, OPEN ACCESS.
JEL CODES:!J24, N32, O14, O31, O34
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*
We wish to thank seminar participants at Stanford and Frank Mueller-Langer for helpful comments.
Moser gratefully acknowledge financial support from the National Science Foundation through NSF
CAREER grant 1151180.
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Electronic copy available at: http://ssrn.com/abstract=2542879
Copyrights protect a broad spectrum of cultural goods ranging from scientific articles and
web content to novels, music, and video games. As the share of copyrighted products
continues to grow, understanding the effects of copyrights becomes critically important.
Historical analyses of copyrights suggest that the adoption of copyright can increase the
quantity and quality of creative work (Giorcelli and Moser 2014). Yet, stronger copyrights
may also create substantial welfare costs by limiting access and discouraging the use of
copyrighted knowledge and cultural goods (e.g., Akerlof et al. 2002; Varian 2005). These
potential welfare losses are particularly severe for science, because the creation of new
knowledge depends on scientists’ ability to access prior knowledge in a process of
cumulative invention (Scotchmer 1991, 2004).
Public interest in open access policies, which make copyrighted journal articles
available for free, is growing rapidly even though there is little systematic evidence on the
effectiveness of these policies (e.g., Evans and Reimer 2009). Empirical analyses in other
fields have shown that improvements in access to biological materials (Furman and Stern
2011) and genetically engineered research mice (Murray, et al. 2009) have encouraged
scientific research. Yet there is no comparable evidence on the effects of reductions in the
costs to access scientific knowledge (which is protected by copyrights) on the production of
new scientific knowledge. Historical analyses have shown that copyrights increase the price
of books (Li, MacGarvie, and Moser 2014) without, however, being able to examine the
effects of access costs on the creation of new knowledge.
To address these issues, this paper examines the effects of the US World War II Book
Republication Program (BRP) on the creation of new knowledge in chemistry and
mathematics. Under the 1942 BRP, 535 science books, which German nationals had
copyrighted in the United States, were licensed to US publishers. The program thus enabled
US publishers to reproduce the verbatim content of German-owned science books (without
the content of German copyright owners) and sell them for a lower price to libraries and
private buyers.
To examine the effects of the BRP on the production of new knowledge we examine
changes in citations to BRP books after 1942, using a new data set of 495 comparable Swiss
books as a control. Like Germany, Switzerland was a significant research source for research
in chemistry and mathematics. Due to Switzerland’s neutrality during the war, Swiss-owned
copyrights were not subject to the BRP, so that the costs of accessing Swiss books remained
high, while access to BRP books became significantly cheaper.
2!
Electronic copy available at: http://ssrn.com/abstract=2542879
Citations data reveal a dramatic increase after 1941 in new research that builds on
knowledge in BRP books, without a comparable change for Swiss data. Citations to BRP
books increased by an additional 0.500 citations per book and year after 1941, compared with
citations to Swiss books. Relative to an average of 0.174 citations per year until 1941, this
implies a 287 percent increase. Geographic data on citations indicate a substantial expansion
in the geographic scope of citations to BRP books. Books that had previously been cited
almost exclusively in metropolitan centers of the North Eastern United States such as
Washington, New York and Baltimore began to be cited in smaller cities (Fort Belvoir VA),
as well as the Midwest (Madison WI) and California (Berkeley). By comparison, citations to
Swiss books remain geographically concentrated in the East around New York, Boston, and
Princeton.
A simple model of cumulative knowledge production, in which scientists decide
whether to build on prior knowledge to produce new knowledge, yields two predictions:
First, the production of new knowledge is weakly decreasing in the costs that scientists must
pay to access existing knowledge (e.g., in the price of accessing a journal article or book).
Price data are available for 492 of 535 books republished under the BRP. These data indicate
that the same book sold for roughly 27 percent less once a US publisher was allowed to
replicate the content of the book. Intensity regressions, which interact the baseline
difference-in-differences estimator with a measure for the decline in price, suggest that a 10percent decline in price was associated with 0.156 additional citations. Compared with an
average of 0.174 citations per year until 1941, this implies a 95 percent increase.
The second prediction is that the effects of cheap access are larger for disciplines in
which knowledge-production is less intensive in physical capital (such as mathematics) than
in disciplines that are more capital-intensive (such as chemistry). In chemistry, the
production of new knowledge depends on laboratory space and other types of physical capital
that are necessary to perform chemical analysis. Unless access to these types of physical
capital increases, too, the benefits of access to prior knowledge are more limited. Triple
differences regressions with an interaction for mathematics confirm this prediction. Citations
to BRP books in mathematics increased by an additional 0.993 per year after 1941, compared
with chemistry. Relative to a mean of 0.174 citations per year until 1941, this implies a 5.7fold increase.
Estimates based on citations to BRP books may, however, overstate the effects of
access to copyrighted materials if books that became more influential after 1942 were more
likely to be re-published under the BRP, or if the research fields that were relevant to Swiss
3!
science became less productive after 1942. To address this issue, we first restrict the sample
to books in the Swiss National Library. Estimates with the restricted sample of books that
were relevant to Switzerland imply a 7.6 fold increase in citations. Next, we estimate intentto-treat regressions to compare citations to German books (that were available for replication)
with citations to Swiss books. We also compare changes in citations for German BRP books
and other German books in the Swiss National Library. These tests indicate that BRP books
were negatively selected (due to their focus on German chemicals) so that OLS estimates will
underestimate the true effects of cheaper access on the use of copyrighted knowledge. A final
test re-estimates the baseline specification with a matched sample of BRP books and Swiss
books (using publication years, research subjects, and publication language as matching
variables).
The remainder of this paper is structured as follows. Section I presents a simple
model of knowledge production, which predicts the effects of changes in price on the creation
of new knowledge, and examines differences across disciplines that are more and less capital
intensive. Section II describes the 1942 Book Replication, and Section III presents the data.
Section IV summarizes the main empirical results, and Section V presents alternative test for
selection. Section VI concludes.
I. THEORETICAL PREDICTIONS
This section presents a simple model of the effects of copyrights on the creation of
new scientific knowledge. For simplicity, let us first consider a single discipline, in which
the production of new knowledge at time t (yt) uses two inputs, prior knowledge (yt-1) and
physical capital (kt, for example in the form of laboratory space). To access prior knowledge
scientists (or R&D workers) must pay p, and to use physical capital scientists must pay r.
The knowledge production function is then yt = f(yt-1, kt).
A scientist decides whether to produce new knowledge and receive the payoff
f(yt-1, kt) –p –rkt (in the form of reputation or monetary compensation) or not to produce new
knowledge and produce a payoff of 0. If the scientist decides to produce new knowledge, he
chooses physical capital to maximize
max$k,Ω$${Ω×[f(yt/1,$kt)$–$p$–$rkt]$+$(1/$Ω)×0} (1)
where Ω={0,1} is a binary variable equal to 1 if new knowledge is produced, and 0 otherwise.
The optimal level of physical capital kt* satisfies the first-order condition
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fk(yt/1,$kt*)$=$r (2)
and the scientist chooses to produce new knowledge if and only if
fk(yt/1,$kt*)$–$p$–$rkt*$≥$0 (3)
At the threshold price p’ = fk(yt-1, kt*) – rkt* scientists are indifferent between producing and
not producing new knowledge yt that builds on prior knowledge yt-1. Scientists produce new
knowledge if and only if p ≤ p’, so that the probability that prior knowledge will be used to
create new knowledge P(p ≤ p’) is a weakly decreasing function in p.
Prediction 1: The creation of new knowledge yt that builds on prior knowledge yt-1 is
(weakly) decreasing in p, the costs of accessing prior knowledge yt-1.
Next we consider the case of two disciplines, which differ in their elasticity of knowledge to
capital. With constant returns to scale, the knowledge production function for the more
capital-elastic discipline (say chemistry) is
yc,t$=$yc,t/1 kt1/γ$
where yc,t is new knowledge and yc,t-1 is prior knowledge. Analogously, we define the
production function for the less capital- elastic discipline (mathematics) as
"
ym,t$=$ym,t/1$=kt1/=$
where ym,t is new knowledge and ym,t-1 is prior knowledge, and γ<µ.
In this case, threshold prices are
!
!! = !
!
!! = !
!!!
!
!!!
!
!!!
!
!!,!!!
!!!
!
(4)
!!,!!! (5)
If prior knowledge is equally valuable across disciplines,1 so that !!,!!! = !!,!!! , and if r ≥ 1
– γ, then !! ! ≥ !! ! . This implies
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1
If !!,!!! < !!,!!! the result does not change. If !!,!!! > !!,!!! and the value of prior knowledge in the
capital-intensive discipline is sufficiently large compared with mathematics then incentives to produce new
knowledge in the capital-intensive discipline are large enough to create a decline in the threshold price that
affects the capital-intensive industry more. Similarly incentives to produce can increase disproportionately
more for the capital-intensive discipline when ! < 1 − ! and physical capital is cheap enough.
5!
Prediction 2: A decline in the costs p of accessing prior knowledge has a (weakly) larger
effect on the production of new knowledge if the elasticity of knowledge with respect to
capital is smaller.2
II. THE WORLD WAR II BOOK REPUBLICATION PROGRAM
A. A Brief History of Copyrights
In 17th-century England, the Stationers’ Company – a group of publishers who had
perpetual monopoly rights over printing – established a registration system to keep track of
works that the Crown had authorized for publication. This system was replaced by the 1709
Statute of (Queen) Anne, which granted authors rather than publishers the right to control
reprints of their work for a limited term of 14 years, renewable for another 14 years if the
author survived the first 14-year term (Deazley 2008).
Modeled after Britain’s Statute of Anne, the US Copyright Act of 1790 offered 14
years of exclusive rights to US authors, with the possibility to renew copyrights for an
additional 14 years. In 1891, the International Copyright Act extended protection to books
by foreign nationals provided that the books had been typeset in the United States
(Manufacturing Clause, Columbia Law Association 1950, p.686). On April 15 1892, the
United States entered a bilateral agreement with Germany (United States Copyright Office,
Circular 38A); this treaty granted national treatment (equal rights to US nationals) to German
nationals in the United States (Kawohl 2008, pp.436-439). In 1909, the U.S. Copyright Act
was revised to extend protection to all works of authorship, including music (Varian 2005, p.
124); in addition, it extended protection to 28 years, renewable for additional 28 years. This
law remained in place until the passage of the 1976 Copyright Act, which extended the length
of copyrights to the duration of the authors’ life plus 50 years after death.
B. The World War II Book Replication Program
On December 18, 1941, 11 days after Japan’ attack on Pearl Harbor, Franklin D.
Roosevelt signed the First War Power Act, which effectively put the 1919 (First War)
Trading with the Enemy Act back into effect, and allowed the US government to seize all
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!!
2!More
generally, p’ is weakly increasing in
:
!!!
!
=
!!
!
!"# !!!"# !!
≥ 0!if!r ≥ 1 −
!.
Intuitively, this implies that the effect of a decline in the price of existing knowledge on knowledge production
is higher for fields that are more cumulative: fields in which the production of new knowledge is more
dependent on access to existing knowledge.
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enemy-owned property.3 Sections 301 and 302 of Title III of the First War Powers Act of
1941,
“granted to the President operating through such agency as he might choose, the power
to investigate, nullify and regulate transactions involving property in which foreign
countries or nationals thereof have an interest and to vest any property or interest of
any foreign country or national thereof in any agency or person whom the President
may designate; such property or interest to be held, used, administered, liquidated, sold
or otherwise dealt with in the interest of and for the benefit of the United States.”
(Myron 1945, p. 77)
On July 6, 1942, the President issued Executive Order No. 9193, which authorized the US
Alien Property Custodian to “direct, manage, supervise, control or vest the following classes
of property: […] Patents, patent applications, copyrights, copyright applications, trademarks,
or trademark applications or rights” (Myron 1945, p. 76). Under this Act the Alien Property
Custodian appropriated more than 10,0000 books with enemy-owned copyrights to US
publishers between 1942 and 1944:
“During the fiscal year 1943 such vesting orders covering some 10,000 titles of
copyrighted works (mostly scientific works and music) have been recorded in the
Copyright Office ….In a number of cases licenses have been issued for the republication
or other use of such vested works.” (Forty-sixth Annual Record of the Register of
Copyrights 1944, p. 8)
These licenses were non-exclusive, and were typically granted for a non-extendable period of
six months (Myron 1945, p. 85).
III. DATA
The main data cover citations between 1920 and 1970 to 535 licensed BRP books and
a control group of 495 Swiss books in the same disciplines.
A. 535 Books that Became Subject to the BRP
For BRP books, information on the title, author, publication year and location,
German publisher, and US publishers for BRP books are drawn from the records of the Alien
Property Custodian (1944, pp. 1- 102). Citations are available for 454 of these books; more
than half of them (236 books, 52 percent) cover chemistry, and 12 percent (55 books) cover
mathematics.
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3 This TWEA delegated “the seizure and control of all property located in the United States owing or belonging
to or held for, by, on account of, or on behalf of, or for the benefit of, a person in an enemy country or enemyoccupied territory or a person proclaimed by the President to be an enemy” (Myron 1945, p. 76). Paul V. Myron
was the Chief of the Estates and Trusts Sec. in the office of the Alien Property Custodian (1942-43), and the
Assistant to the Custodian (1944-45).
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For 492 of 535 BRP books (92 percent), the records of the Alien Property Custodian
also include information on the original and the BRP price of the book. For example,
Waerden, Bartel Leendert Van Der
Moderne Algebra. Berlin, Springer, 1931-1937.
Subject: Algebra.
Original price: $12.80. Republication: $6.00.
Licensee: Frederick Ungar Publishing Co.
On average, these 492 books sold for an original price of $35.10 (with a standard
deviation of 156.43 and a median of $10) and for a BRP price of $16.32 (standard deviation
of 16.32, median $7.5); 423 books with citations data sold for an original price of $38
(standard deviation 168.33, median 10.3). Two hundred and twenty-three chemistry books
with citations data and price information sold for an average original price of $53.31
(standard deviation 202.88, median $11.5) and a BRP price of $23.35 (standard deviation
49.51, median $8.5). Fifty-five books in mathematics with citations data sold for an original
price of $9.84 (standard deviation 5.77, median $8), and a BRP price of $20.23 (standard
deviation of 45.08, median $7.55).
On average, 462 books that experienced a price decline sold for 26.9 percent less
under the BRP (standard deviation 18.4, median $23.9, Figure 1). The book with the largest
price decline, F. Bosnjacovic’s Technische Thermodynamik, sold for an original price of
$1,650 and $15 under the BRP. The book with the median price decline, R. Glocker’s
Materialprüfung mit Röntgenstrahlen unter besonderer Berücksichtigung der
Röntgenmetallkunde (1936) sold for an original price of $13.20, and a BRP price of $9.65.
For 18 books price did not change under the BRP; seven of these books are encyclopedias
and dictionaries. Another 14 books in chemistry (but no books in mathematics) sold for a
higher price under the BRP, all of these books fall in the bottom quartile of original price.
B. Control Group: 495 Swiss Books in the Same Fields
To construct a control group of books that were not subject to the BRP we collect all
books in chemistry and mathematics with publication years between 1921 and 1940 from the
catalog of the Swiss National Library of Bern (Katalog 1921-40).4 This search yields 1,683
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4
Between 1920 and 1970 in Switzerland copyrights were regulated by the Copyright Law of 1922 which
granted protection to authors for 30 years, and subsequently by the Copyright Law of 1955, which extended
copyrights 50 years. This extension was applied to books published before 1955, which were still on copyright
by that date. As a result, the books listed in the catalog of the Swiss National Library and published after 1925
were still on copyright in Switzerland in 1970; books published between 1921 and 1924, on the other hand, saw
their copyright expiring between 1951 and 1954.
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books in chemistry (section 54 of the Swiss National Library) and 447 books in mathematics
(section 51).
To compare knowledge creation for BRP and Swiss books in the same research fields,
we match BRP and Swiss books to 64 mutually exclusive subjects, using the original
classification of the BRP records and the Swiss National Library. The BRP records (Alien
Property Custodian 1942) assign 535 books to 447 topics (such as “catalysis” and “nonEuclidian geometry”); 274 books in chemistry cover 235 topics, and 60 books in mathematics
cover 47 topics; 201 books in 14 other disciplines cover 165 topics (Appendix Table A1).
The Swiss National Library distinguishes 128 topics within chemistry and 28 topics
within mathematics. We combine these topics into 64 mutually exclusive subjects to match
the classification of BRP books.
C. Outcome Variable: 13,956 Books that Cite BRP and Swiss Books 1920-1970
To measure changes in the production of knowledge that builds on prior knowledge,
we accessed Google scholars to collect information on publications with publication years
between 1920 and 1970 that cite the 535 BRP books and 2,130 Swiss books. The algorithm
searches “articles, theses, books, abstracts and court opinions, from academic publishers,
professional societies, online repositories, universities and other web sites.”5 We search
Google Scholars using the title of a book and the author(s) last name(s) as keywords. For
example, to capture books which build on knowledge in
Fischer, Hans
Die Chemie des Pyrrols. Leipzig, Akad. Verlagsgesellschaft, 1934-1940.
Subject: Pyrrol.
Original price: $42.00. Republication: $25.25, set.
Licensee: J. W. Edwards.
we search for books that cite the title (“die Chemie des Pyrrols”) and the author “Fischer.”6
This search yields:
Die Chemie des Pyrrols
H Fischer, H Orth – Akademische, Leipzig, 1937
Cited by 86
We then compare the publication year of the book that is listed in Google Scholar with the
publication year of the book that is listed in the records of the Alien Property Custodian. In
the case of Chemie des Pyrrols, the publication year of the search output (1937) falls into the
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5
Available at http://scholar.google.com, accessed from July 1st to September 25th, 2014.
Hans Fischer (1881–1945, Nobel in chemistry in 1930) was an organic chemist who determined the structures
of pigments in blood and bile as well as chlorophyll in leaves; these substances are derived from pyrrole.
6
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range of publication years that are listed in the BRP records (1934-1940). If Google Scholar
returns more than one match, we collect citations for the version of the book that is closest to
the publication year of the licensed books.7
Eighty-five percent of all BRP books (454 of 535) receive at least one citation
between 1930 and 1970. Among 334 BRP books in chemistry and mathematics 291 (86
percent) are cited at least once, including 236 books in chemistry (81 percent) and 55 in
mathematics (92 percent). Among 2,130 titles with in the Swiss National Library, 567 books
are cited at least once, including 412 books in mathematics (27 percent), 155 books in
chemistry (73.3 percent), and 55 books published in Germany. Until 1941 the average BRP
book receives 0.592 citations per year (Appendix Figure A1, with a standard deviation of
1.250) the average Swiss book is cited 0.060 times a year until 1941, (with a standard
deviation of 0.290). The median BRP book and the median Swiss book received 1 citation
per year until 1941.
We also collect data on citations by English-language books and citations by books in
other languages, to examine whether English-language books (which were more likely to
benefit from the US BRP) were more affected by the BRP. We collect these data by
checking each of the 8,850 citations to BRP books and create a count of citations by Englishlanguage books. 3,817 of 8,850 total citations to BRP books in chemistry and mathematics
are by English-language books, including 317 citations before 1942, and 3,500 afterwards.
Forty-two of 55 books in mathematics (76 percent) and 175 of 236 books in chemistry (74
percent) are cited by at least one English-language book between 1920 and 1970.
The two books with the largest number of English language citations are Topologie by
Paul Alexandroff and Heinz Topf (1935) and Eindeutige Analytische Funktionen by Rolf
Nevanlinna (1936), with 179 English-language citations each. Topologie receives a total of
310 citations in any language; of its 179 English-language citations, only 4 occur before 1942
(44 percent of 9 total citations in any language until 1941), and 175 occur after 1942 (58
percent of a total of 301 citations in any language after 1941). Eindeutige Analytische
Funktionen receives a total of 293 citations; among its 179 English-language citations only 4
occur until 1941 (40 percent of 10 citations in any language until 1941), and 175 occur
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7
Compared with Thomson Reuters’ Web of Science (formerly ISI Web of Knowledge,
http://webofknowledge.com and http://wokinfo.com/nextgenwebofscience), Google Scholar offers more
complete coverage for foreign works, which is essential for our analysis. For roughly five percent of books in
our sample, more than one edition was published in the year that is closest to the original publication year. For
those books, we analyze citations for the edition with the largest number of citations. For 133 books, Google
reports erroneous citations from publications that precede the publication year of the cited books. We omit
these citations from the sample by checking individual citations.
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afterwards (62 percent of 301 total citations after 1941). A third title (in chemistry) received
178 English-citations: Sylloge fungorum omnium hucusque cognitorum by Pier Andrea
Saccardo (1931). It received a total of 282 citations in any language; 49 English language
citations occurred until 1941 (67 percent of 73 total citations in any language until 1941), and
129 after 1941 onwards (62 percent of 209 total citations in any language after 1941)
D. Controls: Language and Publisher Fixed Effects
The large majority of books (519 of 535) were published in German, which had been
the “lingua franca” of the scientific community: “Physicists and chemists in Britain and the
USA could not do without reading German if they wanted to keep abreast of developments in
their fields” (Sarkowski 2001, p. 26). Another 12 books were published in English, 2 in
French and 1 in Latin. There are no noticeable differences between books published in
German, English, French and Latin.8 We leave all books in the sample, and estimate
robustness checks with language fixed effects.
An additional control variable captures variation across publishers, which may have
varied in their marketing and distribution strategies. Seventeen US firms republished books
under the BRP. Among them, J.W. Edwards published 485 of 535 BRP books (90 percent,
Table 1), including 223 titles in chemistry with at least one citation and 37 titles in
mathematics with at least one citation. Books by J.W. Edwards experienced a 24.7 percent
decline on average Dover published another 19 books (5.4 percent of 535 licensed books
total), including 15 in mathematics and 3 in chemistry (5 percent).
Fifty-six publishers distributed the books in the Swiss National Library (Appendix
Table A1). Among them, the ETH Zurich published 370 books including 342 titles in
chemistry and 28 in mathematics. Orell Fussli, published another 27 books in mathematics.
Fifty-four other publishers distributed the remaining 146 books.
We also collect information on the original German publishers for the BRP books,
which we use to identify books in the Swiss National Library that were eligible for the BRP.
A total of 56 German publishers distributed 535 books that were licensed under the BRP
(Appendix Table A2).9
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8
Two French books are Les applications pratiques de la luminescence, fluorescence, phosphorescence, lumiere
noire by M. Déribéré, and La filtration industrielle by G. Genin. The Latin book is Sylloge fungorum omnium
hucusque cognitorum by P. Saccardo. Two of the 12 English books report tables of trigonometric functions;
one is a dictionary of English and Italian The latest modern Italian-English and English-Italian dictionary with
pronunciation by Andrea Lysle de Roever, published by G. E. Stechert & Company in 1943.
9
Robustness checks repeat the baseline specifications with fixed effects for German publishers (Appendix Table
A6) Springer published 233 books (44 percent of all BRP), including 87 in chemistry (37 percent) and 35 in
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E. Robustness: Books by Émigré Mathematicians
We also collect biographical data for all 56 authors of 60 books in Mathematics to
examine whether the arrival of émigré scientists from Germany may have encouraged the
diffusion of knowledge in BRP books. The standard biographical source for émigrés is the
International Biographical Dictionary of Central European Émigrés 1933-1945 by Strauss et
al. (1983); it reports migration dates and countries for 6 of 56 authors of BRP math books.
Another 45 authors are included in the Mathematics Genealogy Project (MGP), which lists
university affiliations, along with the names of advisers and advisees for!a total of 186,596
mathematicians, beginning in the 17th century.10 Based on information from the MGP, we
define émigrés to the United States as BRP authors who advised students at a US university
after 1932.11 Six authors of 5 BRP math books are appear as émigrés in the Dictionary of
Central European Émigrés (Appendix Table A5): Richard Courant (1888-1972, emigrated
1934 after being dismissed from Universität Göttingen in 1932), Philipp Frank (1884-1966,
emigrated 1938), Max Herzberger (1899-1982, emigrated 1935 after his dismissal from the
C. Zeiss Company in 1932), Richard von Mises (1883-1953, emigrated 1939), John von
Neumann (1903-1957, emigrated 1933), George Polya (1887-1985, emigrated 1940), and
George Szego (1895-1985, emigrated 1934).12
US émigrés published three BRP books in mathematics that received at least 1
citation: Richard Courant’s Methoden der Mathematischen Physik (1931, 258 citations, Table
A6), Max Herzberger’s Strahlenoptik (1931, 2 citations), John von Neumann’s
Mathematische Grundlagen der Quantenmechanik (1932, 56 citations), and George Polya
and George Szego’s Aufgaben der Lehrsätze aus der Analysis (1925, 39 citations). These
books sold for $28.24, $7.75, $7.85, and $14.40 originally (compared with an average of
$9.44 for the full sample) and experienced a 45.05 percent decline (with a reproduction price
of $14, $6.5, $3.5, and $6.00 each) in price until 1941, compared with 25.9 percent for the
full sample). Copies of all four books were available for sale on Amazon in February 2015.13!
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mathematics (64 percent). The Akademische Verlagsgesellschaft accounted for another 76 books, including 42
in chemistry and 4 in mathematics.
10
http://genealogy.math.ndsu.nodak.edu, accessed February 1st to 18th, 2015.
12
Two additional authors of BRP books emigrated to Switzerland: Stefan Cohn-Vossen (1902-1936) emigrated
to Switzerland in 1933 after having been dismissed and continued to the USSR in 1935, and Rolf Nevanlinna
(1895-1980) moved to Switzerland after the end of the war, in 1947.
13
Available for sale on http://www.amazon.com accessed February 18th, 2015.
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IV. RESULTS
Until 1941, citation counts followed a similar trend for BRP and Swiss books even
though BRP books were more heavily cited. Citations to BRP books increased from 0.381 in
1932 to 0.652 in 1938 and declined back to 0.510 in 1941. Similarly citations to Swiss books
increased from 0.054 in 1932 to 0.065 in 1938 and declined back to 0.059 in 1941. To allow
for non-linear differences in trends, we estimate pre-trends flexibly through interactions
between BRP books and a year dummy (Table 3, column 5) and present specifications with
linear pre-trends as a robustness check (Appendix Table A7). Between 1941 and 1945, when
the allied bombing campaign destroyed many research facilities in Germany, citations to BRP
books declined from 0.510 in 1941 to 0.450 in 1942, 0.540 in 1943, and 0.292 in 1945.14 At
the same time, citations to Swiss books increased from 0.059 in 1941 to 0.113 in 1942, 0.077
in 1943 and 0.046 in 1945.
After 1945, citations to BRP books increase dramatically, reach a peak of 1.280
citations in 1960, and remain high around 1.100 citation per year until the end of the sample
in 1970. By comparison, citations Swiss books experienced a substantially smaller increase
to 0.145 citations in 1964 and remain flat around 0.15 until 1970 (Figure 2).
A. Baseline estimates
To investigate these changes more systematically we estimate OLS regressions:
cit = α BRPi + β BRPi × postt + δ1 mathi +δ2 pubyear i + τt + εit
(7)
where the dependent variable !!" counts citations to book i per year t between 1930 and 1970.
The indicator variable BRP equals 1 for books that US publishers republished under the Book
Republication Program in 1942; postt is an indicator variable that equals 1 for years between
1942 and 1970. Under the assumption that changes in citations would have been comparable
for BRP and Swiss books after 1941, if BRP had not been replicated and sold for a lower
price, the coefficient β measures the effect of the Book Republication program on the
production of new scientific knowledge. The control variable pubyear is a vector of
publication year fixed effects, which control for the year in which book i was published; it
controls for variation in citations across the life cycle of a book. The variable mathi indicates
books in mathematics. Citation year fixed effects !! !control for unobservable variation in
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
14
Bombings reached a peak of 130 tons per months at the beginning of 1945 (Webster and Frankland 1961,
Annex). Waldinger (2014) finds that a 10 percent increase in the destruction of physical capital reduced
research output by 0.05 standard deviations.
13!
citations over time that is common across BRP and Swiss books, for example as a result of
changes in scientific productivity overall or in the number of new scientific publications
(which could cite BRP and Swiss books per year). Standard errors are clustered at the level
of publication years for citing books, with 29 distinct clusters.
Baseline estimates indicate that BRP books received 0.500 additional citations per
year after 1941 compared with books from Switzerland (Table 3, column 2, significant at 1
percent). Relative to an average of 0.174 citations per year until 1941 for the full sample of
786 BRP and Swiss books, this implies a 287 percent increase. Including language fixed
leaves the estimates unchanged at 0.503 (Table 3, column 3, significant at 1 percent).
Including both publisher fixed effects and language fixed increases the estimate to 0.542
(Table 3, column 4, significant at 1 percent), which implies a 311 percent increase.
Alternative specifications, in which the dependent variable is the natural logarithms of
citations, indicate a 147 percent increase in citations (Appendix Table A13, significant at 1
percent).
B. Pre-trends and Time-varying Effects
We also re-estimate the baseline specification with controls for pre-trends in citations.
Specifically, we repeat the main specification allowing for a nonparametric differential pretrend in citations for BRP books (Σt < 1942 BRPi × τt ). Controlling a differential pre-trends
reduces the size of the estimates to 0.379 (Table 3, column 5), which (relative to a pre-1942
mean of 0.174 citations) implies a 218 percent increase.15
To further examine the timing of the observed increase in citations, we estimate
!! !separately for two-year intervals allowing it to be different from zero until 1941.
cit = α BRPi + Σt βt BRPi × τt + δ1 mathi +δ2 pubyear i + τt + εit
(8)
where the indicator variable !! denotes two-years intervals (1920-21, …., 1968-69), and
1942-43 is the excluded period. Time-varying estimates indicate no significant differences in
citations to BRP and Swiss books until 1941. Time varying estimates are not statistically
significant and vary between -0.698 in 1930-31 and 0.107 in 1938-39 (Figure 3). In the final
years of the war (1944-45), citations to BRP books decline by 0.149 (significant at 1 percent).
Beginning in 1948-49, estimates are positive and statistically significant increase with 0.344
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
15
Alternative specifications with a linear pre-trend (t × BRPi) imply 35.287 additional citations (with a p-value
of 0.147, Appendix Table A7, column 1).
14!
additional citations. Estimates continue to increase to 0.710 additional citations in 1960-61,
and remain large and significant until the final period, with 0.710 additional citations.
C. Robustness: Restricting the Sample to English-language Citations
We also compare changes in citations by English-language authors – who should have
been more likely to benefit from the US BRP program – with citations by books in other
languages, such as French or German. These comparisons indicate a significant differential
increase in citations to BRP books by English-language authors: The average BRP books is
cited 0.153, 0.197, and 0179 times by an English language book in 1935, 1940, and 1942
respectively, and 0.323, 0.285, and 0.270 times by a book in another language (Figure 7).
After 1941 citations by English-language books increase dramatically, to 0.591 citations in
1959, and remain around 0.550 until 1970 By comparison, citations by books in other
languages increase significantly less, to 0.512 in 1959, and remain around 0.5 until 1970. To
test whether this differential increase is statistically significant, we estimate:!
!
citesilt = α Englishl + β Englishl × postt
+ δ1 mathi + δ2 mathi +δ3 pubyeari + τt + εit (12)
where citesilt measures citations to BRP book i in language l and year t, and l = {English,
Other}. Englishl is an indicator variable for citations to BRP book i by English-language
books; postt is defined as above, and the coefficient β for the interaction Englishl × postt
measures the additional increase after 1941 in citations to BRP books by English-language.
OLS estimates for β indicate that BRP books receive 0.074 additional English-language
citations per year compared with citations in other languages (Table 8, column 1, significant
at 1 percent). Compared with an average of 0.550 citations until 1941, this implies a 13
percent increase. Controlling for publisher fixed effects leaves the estimate unchanged (at
0.072, Table 8, column 2, significant at 1 percent).
To examine differences across fields, we re-estimate equation (12) with an additional
interaction term Englishl × mathi× postt with an indicator variable for BRP books in
mathematics. OLS estimates indicate that BRP books in mathematics receive 0.272 additional
citations from English-language books after 1941, compared with BRP books in chemistry
books (Table 8, column 3, significant at 1 percent). Compared with an average of 0.550, this
corresponds to an additional increase by 49 percent increase. The inclusion of publisher
15!
fixed effects increases the estimate to 0.308 additional citations (Table 8, column 4,
significant at 1 percent).
We also estimate a differential effect for BRP books that experienced a larger decline
in price in 1942:
citesilt = α Englishl + β Englishl × postt + φ Englishl × p declinei × postt
+ δ1 mathi + δ2 mathi +δ3 pubyeari +δ4 p declinei + τt + εit (13)
These regressions indicate that a 10 percent decline in price in 1942 is associated with 0.056
additional citations per year by English-language books after 1941. Compared with a pre1942 average of 0.550 citations per year, this implies a 10 percent increase in citations by
English-language books (Table 8, column 5, significant at 1 percent). Including an additional
interaction term for BRP books in mathematics Englishl × p declinei × mathi ×postt indicate
that a 10 percent decline in price leads is associated with 0.162 additional English citations
for BRP books in mathematics books compared with chemistry (Table 8, column 7,
significant at 1 percent), which corresponds to a 29 percent increase in citations.
D. The Response of Citations to Changes in Price
To investigate the effects of changes in the costs of prior knowledge on the
production of new knowledge we estimate OLS regressions with an interaction term that
captures the decline in price under the BRP:
citesit = α BRPi + β BRPi × postt +γ price declinei + θ price declinei ×BRPi × postt
+ δ1 mathi +δ2 pubyeari + τt + εit (9)
where the variable price declinei measures the difference between the original price and BRP
price for book i divided by the original price.
These regressions indicate that a 10-percent the decline in price is associated with
0.156 additional citations per year after 1941 (Table 4, column 2, significant at 1 percent).
Compared with an average of 0.174 citations per year until 1941 for 263 books with price
data, this implies a 90 percent increase. Re-estimating the baseline model without the
interaction term (equation 7) for books with price data yields estimates that are nearly
identical to estimates for the full sample (0.544 in Table 3, column 6, significant at 1 percent,
compared with 0.542 for the full sample in Table 3, column 4).
We also estimate time-varying effects for this specification:
16!
citesit = α BRPi + β BRPi × postt +γ price declinei + Σt θt price declinei ×BRPi ×
postt + δ1 mathi +δ2 pubyeari + τt + εit (10)
Time varying estimates indicate no significant differences in citations until 1941 (Figure 4).
Between 1943 and 1945, citations to BRP books experience no significant change in citations
(with an estimated decline of 0.000 citations per year, not statistically significant). Citations
start to increase after 1948, with an estimated 0.279 additional citations in 1956-7 for a 10percent reduction in price in 1942.
E. Heterogenous Effect across Fields: Mathematics vs. Chemistry
We also examine whether improved access created heterogeneous effects in chemistry
and mathematics. These comparisons indicate that the effect of improved access to
copyrighted knowledge was substantially larger for mathematics (a field that is more intense
in human capital and less dependent on physical capital) and smaller for chemistry (a field
that is more dependent on physical capital, for example in the form of laboratory space).
In chemistry, citations to licensed books increased from 0.592 citations per year until
1941 to 0.753 per year after 1941 (Figure 5, top panel). Citations to Swiss books increased
from 0.060 per year until 1941 to 0.090 after 1941. In the final years of the war, citations for
BRP books decline from 0.472 in 1942 to 0.245 in 1945, and citations to Swiss books
declined from 0.097 in 1942 to 0.052. After 1945, citations to BRP increased to 1.004 in
1960, and stayed at that level until 1970.
By comparison, BRP books in mathematics experienced a substantially larger
differential increase in citations after 1941. Until 1941, BRP books in math received 0.409
citations per year and Swiss books receive 0.060 (Figure 5, bottom panel). After 1941,
citations to BRP books increase dramatically from 0.490 citations in 1945 to 2.47 in 1960,
while citations to Swiss books decline to 0.026 in 1945 and 0.177 in 1960.
To investigate these effects more systematically, we estimate
citesit = α BRPi + β BRPi × postt + δ1 mathi +φ mathi × BRPi × postt
+δ2 pubyeari + τt + εit (12)
where mathi is an indicator variable equal to 1 for books in mathematics.
The coefficient φ for the interaction term mathi × BRPi × postt tests prediction (2) of
the theoretical model. If the production of new knowledge benefits more from reductions in
the price of access in disciplines that are less capital-intensive, φ should be positive. An
estimate of 0.982 for φ fails to reject this hypothesis (Table 5, column 1, significant at 5
percent). BRP books in mathematics books receive 1.243 additional citations per year after
17!
1941 (BRP x post + BRP x math x post, Table 5, column 1, significant at 5 percent); relative
to an average of 0.174 citations per year until 1941, this implies a 7.1-fold increase. By
comparison, BRP books in chemistry received only 0.261 additional citations compared with
Swiss books after 1941 (BRP x post, Table 5, column 1, significant at 1 percent); relative to
an average of 0.174 citations per year until 1941, this implies a 1.5-fold increase. Controlling
for language fixed effects increases the estimate for BRP x Mathematics x post to 0.993
(Table 5, column 2, significant at 5 percent) and leaves the estimate for BRP x post
unchanged at 0.262 (significant at 1 percent).16
Estimates with an additional interaction term for price indicate that a 10-percent
decline in price is associated with an additional 0.384 increase in citations for BRP books in
mathematics (BRPi × mathi × decline in p × postt, Table 5, column 1, significant at 5
percent ). For a 10-percent decline in price BRP books in mathematics receive 0.459
additional citations after 1942 (BRPi × decline in p × postt + BRPi × mathi × decline in p ×
postt, Table 6, column 1, significant at 5 percent). Relative to a mean of 0.174 citations until
1941, this implies a 264 percent increase. By comparison, BRP books in chemistry receive
0.075 additional citations for chemistry, but the coefficient is not statistically significant
(with a p-value of 0.12).
F. Heterogenous Effects for Books by US Émigrés
A potential complementary channel for the diffusion of scientific knowledge is the
arrival of émigré scientists who fled the Nazi regime after 1933 and arrived in the United
States in the 1930s and 1940s (e.g., Moser, Voena, and Waldinger 2014). To examine this
channel, we examine biographical data for the authors of mathematics, and separately
estimate changes in citations to mathematics BRP books by émigrés and other German
mathematicians.
Summary statistics indicate that books by émigrés were more heavily cited until 1941
and experienced explosive growth in citations until. Until 1941, BRP books by émigrés
receive roughly 37 percent more citations than BRP books by other German scientists, and
citations to both types of books grow at comparable rates. Books by émigré mathematicians
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
16
Controlling for language and publisher fixed effects leads to a small decline in the estimate for BRP x
Mathematics x post (0.736 Table 5, column 3, significant at 10 percent) and increases the estimate for BRP x
post to 0.366 (significant at 1 percent). Controlling for pre-trends leaves the estimate for BRP x Mathematics x
post substantially unchanged at 0.983 (Table 5, column 4, significant at 5 percent), and reduces the estimate for
BRP x post to 0.176 (significant at 10 percent). Controlling for linear pre-trends increases the estimate for
mathematics books to 0.955 (Appendix Table A7, column 2, significant at 5 percent), whereas the estimate for
chemistry is not statistically significant.
18!
receive 0.5 citations per book in 1934, and 0.75 citations in 1940 and 1941, whereas books by
other German chemists receive 0.35 citations in 1934, 0.325 in 1940 and 0.689 in 1941. After
the end of the war, citations to books by non-US émigrés increase to 2 citations in 1953, and
remain high around 2 citations until 1965. Citations to books by US émigrés, however,
increase dramatically more to 3.25 citations per year in 1953, drop to 1 citation in 1964, and
return to 3.5 citations in 1970 (Figure 6).
To systematically evaluate the differential change in citations for émigré BRP books,
we re-estimate the baseline specification on the subsample of mathematics books, with an
additional interaction term for émigrés to the United States:
citesit = α BRPi + β BRPi × postt +γ US emigrei +φ US emigrei × BRPi × postt
+δ2 pubyeari + τt + εit (11)
where US emigrei equals 1 for books whose author moved to the United States after 1932.
The coefficient
measures the incremental increase in citations after 1941 for books by US
émigrés. OLS estimates for φ indicate that BRP books by émigrés receive 0.932 additional
citations per year compared with other BRP books (Table 7, column 1, significant at 1
percent). Compared with an average of 0.155 citations for all BRP books until 1941, this
implies a 6-fold increase.
OLS estimates of the coefficient φ for the interaction US emigre x BRP x post,
indicate that BRP mathematics books by émigré German authors scientists received 0.932
additional citations per year after 1941 (Table 7, column 1, significant at 1 percent).
Estimates of
indicate that BRP mathematics books by other (non-émigré) German authors
scientists received 1.233 additional citations per year after after 1941 (BRP x post,Table 7,
column 1, significant at 1 percent). Relative to a baseline estimate of 1.243 (Table 7, column
1) this estimate suggests that only a small portion of the observed increase in citations was
driven by émigrés.
Intent-to-treat estimates of the effect of migration to any country indicate that BRP
books by non-émigré authors, regardless of the country, receive 1.041 additional citations per
year after 1941 (Table 7, column 4, significant at 1 percent), which implies a 7-fold increase
compared with an average of 0.155 citations until 1941). BRP books by émigrés, on the
other hand, receive 2.113 additional citations per year (Table 7, column 4, significant at 1
percent). Controlling for language fixed effects slightly increases the estimate of
additional citations per year, and slightly reduces the estimate of
to 1.051
to 2.079 (Table 7,
19!
column 5, significant at 1 percent). The inclusion of publisher fixed effects further increases
the estimate of
to 1.137 additional citations per year, and reduces the estimate of
to
1.965 additional citations (Table 7, column 6, significant at 1 percent).
G. An Expansion in the Geographic Scope of Citations
Citations data indicate a substantial westward expansion in the geographic scope of
citations to BRP books. Bartel L. van der Waerden’s Moderne Algebra (Springer, 1931) was
one of the most widely used textbooks in abstract algebra (Behan and Sigmund 2008, p. 33),
and is ranked 7th in terms of citations among books under the BRP, with 224 citations. Data
on the location of the citing publication are available for 175 of these citations. These data
indicate that until 1941, citations to Moderne Algebra were geographically concentrated in
Washington DC (3 citations), Princeton NJ (2 citations), Baltimore MD (1 citation), Bethesda
MD (1 citation), and Durham NC (1 citations) until 1941 (Appendix Figure A2A). After
1941, the geographic scope of citations expands to include Cambridge MA (3 citations), Fort
Belvoir VA (2 citations), New York NY (6 citations), Philadelphia PA (9 citations), Madison
WI (1 citations), Ann Arbor MI (3 citations), San Francisco CA (1 citation), Stanford CA (1
citation), Berkeley CA (5 citations), and Santa Monica CA (1 citation).
The German book Topologie by Paul Alexandroff and Heinz Topf, originally
published by Springer in Germany, and licensed to J. W. Edwards received 310 citations;
data on the location of the citing publication are available for 264 of them. Similar to
Moderne Algebra, publications that cite Topologie were geographically concentrated until
1941in Princeton NJ (1 citation), Ann Arbor MI (1 citation), Washington DC (1 citation), and
Durham NC (1 citation, Appendix Figure A2C). After 1941, the geographic scope of
publications that cite Topologie expands to include Cambridge MA (2 citations), New York
NY (3 citations), Fort Belvoir VA (2 citations), Philadelphia PA (6 citations), Gainesville FL,
Chicago IL, Ann Arbor MI (3 citations), and Berkeley CA (6 citations).
By comparison the scope of citations to Swiss books remains substantially more
limited. For example, the Eduard Stiefel’s Richtungsfelder und Fernparallelismus in ndimensionalen Mannigfaltigkeiten (E.T.H., 1935) is among the most cited Swiss books.
Stiefel (1909-1978) was a mathematics professor in Zurich, and well-known as the coinventor of the conjugate gradient method and the study of characteristic classes. Geographic
data are available for 38 of 47 publications that cite Richtungsfelder.17 Similar to Moderne
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
17
Stiefel founded the Institute for Applied Mathematics in Zurich, and taught at the ETH from 1948 until his
death in 1978.
20!
Algebra, citations are geographically until 1941 concentrated in Washington DC (1 citation)
and Cambridge MA (1 citation, Appendix Figure A2B). Unlike Moderne Algebra and
Topologie, however, the geographic scope of citations remains narrow after 1941 in
Washington DC (10 citations), and Princeton NJ (7 citations). Another Swiss book Das
Randverhalten der Ableitung der Abbildungsfunktion bei konformer Abbildung by Stephan E.
Warschawski (1932) receives 42 citations between 1921 and 1970 (Appendix Figure A2D).
Location data are available for 36 of these citations. Similarly to Richtungsfelder, citations to
this book until 1941 are concentrated, with one single citation in Washington DC. After
1941, the scope of citations extends to Waltham MA (1 citation), New York NY (2 citations),
Durham NC (1 citation), Indiana (2 citations), Denton TX (1 citation), and Berkeley CA (3
citations).
H. Robustness: Excluding Dissertations from the Control
Compared with the sample of licensed German books, Swiss entries in the catalog
include a larger number of PhD dissertations (875) and master’s theses (407, Appendix Table
A2).18 In robustness checks (Appendix Tables A10 and A11) we re-estimate our baseline
specifications excluding dissertations and theses, which tend to be cited less).19
V. TESTS FOR SELECTION
A potential issue with interpreting the baseline estimates is that they may overstate the
effect of reductions in the costs of access to prior knowledge if books that experienced a
larger increase in citations after 1941 were more likely to be selected for the BRP. A related
issue is that books in the control group were selected for their relevance for the Swiss market
and may have experienced a smaller increase in citations after 1941 due to this selection.
We also re-estimate the baseline specification with a matched sample of 205 BRP
books and 69 Swiss books (based on Mahalanobis propensity score matching using
publication year, research subject, and publication language as matching variables).
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
18
Excluding dissertations and masters’ theses from the sample, average Swiss book is cited 0.088 a year, with a
standard deviation of 0.356, and the median book is cited once a year.
19
Dissertations account for 255 Swiss books in chemistry (67 percent) and 49 books in math (42 percent).
Estimates are robust to excluding dissertations: OLS estimates indicate that BRP books received 0.534
additional citations per year after 1941 compared with Swiss books (Appendix Table A10, column 2, significant
at 1 percent). Regressions with an interaction term for price indicate that a 10 percent decline in price is
associated with 0.151 additional citations (Appendix Table A11, column 1, significant at 1 percent). These
results are robust to controlling for language fixed effects, publisher fixed effects, and pre-trends in citations. !
21!
Estimates with the matched sample indicate that BRP books received 0.587 additional
citations, which implies a 135 percent increase.
A. Restricting the Sample to Books in the Swiss National Library
To address these issues, we first restrict the sample to 495 Swiss and 11 BRP books in
the Swiss National Library; both types of books are selected for their relevance to
Switzerland. Only 11 of these books were republished under the BRP, including 6 in
chemistry and 5 in mathematics (Appendix Table A12).
Summary statistics indicate that the differential increase in citations for BRP books is
even larger for books in the Swiss National Library compared with the full sample, possibly
the restricted sample includes a larger share of BRP books in math. On average, citations to
BRP books increased by 225 percent from 0.520 per year until 1941 to 1.690 afterwards
(Appendix Figure A5), while citations to Swiss books increased by only 61 percent from
0.067 until 1941 to 0.108 afterwards. Ten BRP books in the Swiss National Libraries
received 1.67 citations on average in 1932, 1.000 in 1934, 0.111 in 1936, and 0.727 in 1940.
Swiss books not in the BRP receive 0.054 citations in 1932, 0.074 in 1934, 0.096 in 1936,
and 0.085 in 1940. Citations drop to 0 for BRP books and to 0.046 for Swiss books in 1945.
After 1945 citations to BRP books increase to 2.636 citations per year in 1964, and remain
around 1 until 1970. By comparison, Swiss books receive 0.145 citations in 1964, and
remain below 0.2 through the remainder of the sample.
Estimates with this restricted sample indicate that BRP books received 0.675
additional citations after 1941 (Table 9, column 1, significant at 10 percent). Compared with
an average of 0.089 citations per year until 1941 for all books in the Swiss National Library,
this implies a 7.6 fold increase, whereas estimates for the full sample imply only a 2.9 fold
increase.
B. Intent-to-treat Regressions for Books with German-owned Copyrights
In the next step of the analysis we investigate the direction of selection within the
sample books in the Swiss National Library to compare citations to 55 German books (that
were available for replication) with citations to 495 Swiss books (that were not available for
replication). German books are the treated variable. Eleven of 55 German books in the
Swiss National Library were licensed to US publishers under the BRP. Compared with BRP
books, German books in the Swiss library include a higher share of mathematics, with 27
books in in chemistry and 28 in mathematics.
22!
Summary statistics indicate a substantial increase in citations for books with Germanowned copyrights after 1941 (Appendix Figure A6). Citations to German books increase
from an average of 0.277 citations per year until 1941 to 0.423 afterwards, while citations to
Swiss books increase from 0.067 before 1942 to 0.108 afterwards. Citations to both Swiss
and German books decline in the final year of World War II. Citations to German books
increase to 0.800 citations in 1958, and remain around high, with 0.436 citations in 1970. By
comparison, Swiss books receive 0.128 citations in 1958, and remain around 0.130 through
the remainder of the sample.
With the caveat that these effects are estimated for a substantially smaller sample,
they suggest that BRP books are negatively selected. Due to the small size of the Swiss
sample, OLS are not statistically significant (with a p-value of 0.2) but the coefficient is large
at 0.146 (Table 9, column 3), implying a 292 percent increase. Compared with an uptake
ratio of 1 in 5, this estimate implies a treatment on the treated (TOT) estimate of 0.146/0.20,
which equals 0.730. Compared with an OLS estimate of 0.500 (Table 3, column 2) this
suggests that BRP books may have been negatively selected.
C. German Books in Switzerland but not in BRP as a control for German Books in BRP
We also compare changes in citations for 11 German books that were selected for the
BRP with changes for 44 German books in the Swiss National Library that were not selected.
Both groups of books were of interest to Swiss and German science, but only BRP books
were replicated in 1942. Citations to BRP and other German books were extremely close
until 1941. In 1930, for example, BRP books received 0.400 citations and other German
books in the Swiss National Library received 0.323 citations (Figure 8). After 1945, citations
to BRP books increase dramatically and citations to other German books experience no
comparable change. Citations to BRP books increase to 2.000 in 1949, 1.450 in 1952 and
1.180 in 1955, whereas citations to other German books experience a much more limited and
slower increase in citations, with 0.227 citations in 1949 and 1952, and 0.363 citations in
1955.
OLS regressions indicate that BRP books receive 0.668 additional citations per year
after 1941 compared with other German books, (Table 9, column 5, p-value of 0.12).
Compared with an average of 0.237 citations per year until 1941 for all German books in the
Swiss National Library this implies a 282 percent increase.
D. Propensity Score Matching
23!
We also re-estimate the baseline specification with a matched sample, using
Mahalanobis propensity score matching with publication years, publication languages, and
research fields as matching variables. The matched sample includes 205 BRP books in math
and chemistry and 69 Swiss books (Appendix Table A13). Forty-five of 205 BRP books (22
percent), and 24 of 69 Swiss books (35 percent) are in mathematics.20
With a coefficient of 0.560 (Table 10, column 1, significant at 1 percent) baseline
estimates for the matched sample are slightly larger than the estimates for the full sample
(0.500, Table 3, column 2, significant at 1 percent). Compared with a pre-1942 average of
0.436 citations per year, this implies a 128 percent increase. Controlling for language and
publisher fixed effects increases the size of the estimate to 0.587 (Table 10, column 2,
significant at 1 percent), which implies a 1.35-fold increase.
Regressions with an interaction term for price indicate that a 10-percent decline in
price was associated with 0.140 additional citations per year after 1941 (Table 10, column 3,
significant at 1 percent). This effect is slightly smaller than the OLS estimate of the full
sample (0.156, significant at 1 percent, Table 4). Compared with a pre-1942 average of
0.417 citations per year to books in the matched sample, it implies a 34 percent increase.
Controlling for language and publisher fixed effect increases the effect to 0.154 additional
citations per year (Table 10, column 4, significant at 1 percent).
VI. CONCLUSIONS
This paper has examined the effects of the 1942 Book Republication Program (BRP),
which allowed US publishers to replicate the content of German science books, on the
production of new knowledge. Citations data indicate a dramatic increase in citations to
German science books after 1941 compared with a control group of comparable Swiss
science books whose copyrights remained intact. This effect is larger for books that
experienced a larger decline in price under the BRP. These findings indicate that policies
which reduce the costs of accessing scientific content – such as making journal articles
available for free online – can in fact encourage the production of new scientific knowledge.
In the case of the BRP, copyrights were transferred to another publisher who made
additional copies of the same book, and sold them for a lower – albeit positive - price. This
suggests that policies that reduce the costs of accessing copyrighted contents can encourage
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
20
See Appendix Tables A5 and A6 for summary statistics, and Appendix Figures A3, A4 and A5 for citations
per year both disciplines.
24!
diffusion and the production of new knowledge – without making these materials available
for free.
Another result of our analysis is that reductions in access costs are more effective for
disciplines, in which the creation of new knowledge is more dependent on human capital and
less dependent on physical capital. A simple model of knowledge production predicts a
differential boost to the creation of new knowledge for disciplines that are less capital
intensive. Citations data confirm this prediction: Citations to BRP books increased
substantially more for mathematics (which depends almost exclusively on human capital)
than chemistry (which is more dependent on laboratory space and other types of physical
capital). These findings indicate that the welfare benefits of reduced access costs are largest
in less capital-intensive industries.
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27!
0
20
Frequency
40
60
FIGURE 1 – PERCENTAGE DECLINE IN PRICE FOLLOWING COMPULSORY LICENSING
0
.2
.4
.6
Decline in P (%)
.8
1
Notes: The x-axis variable decline in price measures the percentage decline in price
for 462 books by German authors that were published in the United States and became
subject to the Book Replication Program (BRP) in 1942. It is calculated as {(p
original – p reproduction)/p original}. Price data are drawn from the records of the
Alien Property Custodian (1942). Price data are available for 492 of 535 books that
became subject to the program. In addition to the 462 books that experienced a
decline in price, 48 experienced no change in price, and 25 experienced a price
increase.
FIGURE 2 – CITATIONS PER YEAR
Notes: Citations per year for 291 BRP books in chemistry and mathematics that
were published in Germany between 1920 and 1944 and subject to BRP, and to 495
Swiss books in chemistry and mathematics in the National Swiss Library. To collect
citations to these books we accessed Google Scholar (http://scholar.google.com)
between July 1st and September 25th, 2014.
FIGURE 3 – TIME-VARYING EFFECT OF BRP ON CITATIONS PER YEAR
Notes: Point estimates and 95% confidence intervals for the coefficients in the OLS
regression cit = α BRPi + Σt βt BRPi × τt + +δ pubyear i + τt + εit .The baseline
year is 1942. The subscript i denotes each book, t denotes year of publication of the
citing books, !"#! =1 for 275 books licensed in 1942 under the effect of the TWEA,
the variable τ! is an indicator variable for each two-years period following 1920, the
variable pubyear is a vector of publication year fixed effects, which control for the
year in which book i was published, the variable mathi indicates books in
mathematics. The sample includes citations for 291 BRP books in chemistry and
mathematics that were published in Germany between 1920 and 1944 and subject to
BRP, and to 495 Swiss books in chemistry and mathematics in the Swiss National
Library. To collect citations to these books we accessed Google Scholar
(http://scholar.google.com) between July 1st and September 25th, 2014.
FIGURE 4 – TIME-VARYING EFFECTS OF A DECLINE IN PRICE DECLINE ON CITATIONS
Notes: Point estimates and 95% confidence intervals for the coefficients θ! in the
OLS regression cit = α BRPi + β BRPi × postt +γ price declinei + Σt θt price declinei
×BRPi × postt +δ pubyeari + τt + εit.!The baseline year is 1942. The subscript i
denotes each book, t denotes year of publication of the citing books, !"#! =1 for 291
books published in Germany and subject to the BRP, the variable τ! is an indicator
variable for each two-years period following 1920, the variable price declinei
measures the difference between the original price that the German publisher
changed in the United States for book i and the price that the US publisher charged
under the BRP divided by the price that the German publisher had charged, the
variable pubyeari is a vector of publication year fixed effects, which control for the
year in which book i was published. The sample includes citations for 291 BRP
books in chemistry and mathematics that were published in Germany between 1920
and 1944 and licensed to a US publisher in 1942, and to 495 Swiss books in
chemistry and mathematics in the National Swiss Library. To collect citations to
these books we accessed Google Scholar (http://scholar.google.com) between July
1st and September 25th, 2014.
FIGURE 5 – AVERAGE CITATIONS PER YEAR, CHEMISTRY (TOP PANEL) AND MATHEMATICS (BOTTOM
PANEL)
Notes: Top figure: citations per year for 236 BRP books in chemistry that were
published in Germany between 1920 and 1944 and subject to the BRP, and to 412
Swiss books in chemistry in the National Swiss Library. Bottom figure: citations per
year for 55 BRP books in mathematics that were published in Germany between
1920 and 1944 and subject to BRP, and to 155 Swiss books in mathematics in the
National Swiss Library. To collect citations to these books we accessed Google
Scholar (http://scholar.google.com) between July 1st and September 25th, 2014.
FIGURE 6 – CITATIONS PER YEAR – US EMIGRES VS. NON-US EMIGRES
Notes: Citations per year for 5 BRP books in chemistry and mathematics by authors
who migrated to the US during their career, and 286 BRP books by authors who did
not migrate to the US. To collect citations to these books we accessed Google
Scholar (http://scholar.google.com) between July 1st and September 25th, 2014.
FIGURE 7 – AVERAGE CITATIONS PER YEAR – ENGLISH VS. OTHER LANGUAGES
Notes: Citations per year in English language and in other languages for 236 books
in chemistry and 55 books in mathematics in the Swiss National Library, published
in Germany subject to BRP. To collect citations to these books we accessed Google
Scholar (http://scholar.google.com) between July 1st and September 25th, 2014.
FIGURE 8 – AVERAGE CITATIONS PER YEAR – GERMAN BOOKS IN SWISS “KATALOG”
Notes: Citations per year for 11 books in chemistry and mathematics in the Swiss
National Library published in Germany subject to BRP, and to 44 books published in
Germany but not subject to BRP. To collect citations to these books we accessed
Google Scholar (http://scholar.google.com) between July 1st and September 25th,
2014.
FIGURE 9 – AVERAGE CITATIONS PER YEAR – AVERAGE CITATIONS PER YEAR – MATCHED SAMPLE
Notes: Citations per year for 205 BRP books in chemistry and mathematics that
were published in Germany between 1920 and 1944 and licensed to a US publisher
in 1942, and to 69 Swiss books in chemistry and mathematics in the Swiss National
Library. This subsample is obtained using a Mahalanobis matching procedure based
on year of publication, field, language and finer subjects. To collect citations to these
books we accessed Google Scholar (http://scholar.google.com) between July 1st and
September 25th, 2014.
FIGURE 10 – AVERAGE CITATIONS PER YEAR – MATCHED SAMPLE, MATHEMATICS (TOP PANEL) AND
CHEMISTRY (BOTTOM PANEL)
Notes: Top panel: citations per year for 45 BRP books in mathematics that were
published in Germany between 1920 and 1944 and licensed to a US publisher in
1942, and to 24 Swiss books in mathematics in the Swiss National Library. Bottom
panel: citations to per year for 160 BRP books in chemistry that were published in
Germany between 1920 and 1944 and licensed to a US publisher in 1942, and to 42
Swiss books in chemistry in the Swiss National Library. This subsample is obtained
using a Mahalanobis matching procedure based on year of publication, field,
language and finer subjects. To collect citations to these books we accessed Google
Scholar (http://scholar.google.com) between July 1st and September 25th, 2014. !
TABLE 1 – U.S.US LICENSEES OF BOOKS UNDER THE “BOOK REPUBLICATION PROGRAM”
Licensee
J. W. Edwards
Dover Publications
Frederick Ungar Publishing Company
Philosophical Library
Mary S. Rosenberg
Prof. R. Courant
Academic Press, Inc.
D. Van Nostrand
Dr. R. A. Kehoe, U of Cincinnati
Elsevier
G. E. Stechert & Company
G. P. Putnam's Sons
G.E. Stechert
Grune & Stratton
Interscience Publishers.
Schwarz Laboratories, Inc.
Williams & Wilkins
Others
Full sample
Mathematics
Chemistry
N
Original p
BRP p
N
Original p
BRP p
N
Original p
BRP p
485
19
7
4
3
2
1
1
1
1
1
1
1
1
1
1
1
4
37.38
9.58
19.58
3.34
28.16
21.08
27.20
10.00
15.12
9.07
3.00
10.50
2.00
11.20
17.28
3.20
11.75
17.11
4.34
13.32
3.25
14.25
10.75
17.00
7.50
4.00
3.75
4.00
6.00
0.48
5.00
6.00
5.00
5.00
37
15
1
0
0
1
0
1
0
0
0
0
0
0
0
0
0
0
9.54
9.14
12.80
--28.24
-10.00
----------
7.87
3.98
6.00
--14.00
-7.50
----------
223
3
0
3
0
0
1
0
1
1
0
0
0
0
1
0
1
2
55.52
13.92
-3.65
--27.20
-15.12
9.07
----17.28
-11.75
24.10
6.67
-3.00
--17.00
-4.00
3.75
----6.00
-5.00
Notes: List of the US publishers of 535 BRP books. “Others” include 4 books with missing licensee information. The mathematics and chemistry samples refer
to books with citation data. BRP books are collected from the Report of the Alien Property Custodian (1942).!
!
TABLE 2 – COMPARISON OF MEANS
CITATIONS PER BOOK AND YEAR BRP AND SWISS BOOKS
1920-41
1942-1970
Difference
Full
Sample
(N=786)
!
!
!
!
0.416
(1.440)
0.940
(2.167)
0.107
(0.455)
0.856***
(0.022)
!
BRP
(N=291)
!
!
!
Swiss
(N=495)
!
!
!
Difference
!
!
!
!
!
Chemistry
(N=618)
!
!
0.171
(0.679)
0.550
(1.250)
0.060
(0.290)
0.507***
(0.021)
0.244***
(0.070)
0.391***
(0.054)
0. 048***
(0.006)
0.489***
(0. 018)
!
!
0.343
(1.159)
0.753
(1.743)
0.090
(0.365)
0.663***
(0.017)
!
BRP
(N=236)
!
!
!
Swiss
(N=382)
!
!
!
Difference
!
!
!
!
!
Mathematics
(N=168)
!
!
0.175
(0.708)
0.592
(1.338)
0.060
(0.292)
0.532***
(0.021)
0.168***
(0.016)
0.161**
(0.051)
0.030***
(0.006)
0.131***
(0.036)
!
0.155
(0.542)
0.409
(0.885)
0.060
(0.281)
0.349***
(0.031)
!
0.682
(2.109)
1.741
(3.317)
0.167
(0.673)
1.574***
(0.070)
!
0.527***
(0.056)
1.332***
(0.168)
0.107***
(0.021)
1.225***
(0.116)
!
!
!
!
!
!
BRP
(N=55)
!
Swiss
(N=113)
!
Difference
!
Notes: Means and standard deviations (in parentheses) of citations per year to 291 BRP books in
the fields of chemistry and mathematics, and to 495 books in the Swiss National Library
published in Switzerland in the same fields. Book data are collected from the Report of the Alien
Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen
oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H.
Huber. Citations data are collected from Google Scholar (http://scholar.google.com), accessed
July 1st-September 25th, 2014. from Google Scholar (http://scholar.google.com), accessed July
1st-September 25th, 2014.!!
!
!
TABLE 3 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
Full Sample (1-5)
(1)
(2)
(3)
(4)
(5)
Sample w.
price data
(6)
BRP
0.398*** 0.396*** 0.400*** 1.784*** 0.516***
1.524***
(0.071) (0.076) (0.078) (0.380) (0.094)
(0.378)
BRP x post 0.481*** 0.500*** 0.503*** 0.542*** 0.379***
0.544***
(0.094) (0.098) (0.099) (0.106) (0.079)
(0.106)
Mathematics
0.283** 0.289**
0.173
0.284**
0.166
(0.114) (0.114) (0.104) (0.114)
(0.103)
Citat. year
Yes
Yes
Yes
Yes
Yes
Yes
FE
Pub. year FE
Yes
Yes
Yes
Yes
Yes
Yes
Language FE
No
No
Yes
Yes
No
Yes
Publisher FE
No
No
No
Yes
No
Yes
Pre-trend
No
No
No
No
Yes
No
R-squared
0.131
0.138
0.139
0.194
0.139
0.196
N
29,971
29,971
29,971
28,451
29,971
28,076
Pre-42 mean
.174
.174
.174
.179
.174
.179
Standard errors are clustered at the level of publication years.
*** p<0.01, ** p<0.05, * p<0.1
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to
1970. The variable BRP equals 1 for 291 BRP books in the fields of chemistry and
mathematics. The control consists of 495 books in the Swiss National Library published in
Switzerland in the same fields. The variable post equals 1 for years after 1942. The variable
Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to US licensees
for BRP books, and to Swiss publishers for Swiss books. Book data are collected from the
Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches
Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols.
1921-1939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com) accessed July 1st-September 25th, 2014.
!
!
TABLE 4 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
(1)
(2)
(3)
(4)
(5)
BRP
0.267** 0.273** 0.281** 4.188*** 0.372***
(0.107)
(0.107)
(0.108)
(0.663)
(0.094)
BRP x post
0.026
0.043
0.042
0.007
-0.052
(0.120)
(0.121)
(0.122)
(0.127)
(0.111)
Decline in p
0.491
0.465
0.448
-0.135
0.446
(0.391)
(0.380)
(0.377)
(0.528)
(0.393)
BRP x Decline in p x post
1.562*** 1.565*** 1.575*** 1.805*** 1.565***
(0.453)
(0.446)
(0.448)
(0.506)
(0.448)
Mathematics
0.268** 0.274**
0.203
0.269**
(0.106)
(0.106)
(0.103)
(0.107)
Citation Year FE
Yes
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Yes
Language FE
No
No
Yes
Yes
No
Publisher FE
No
No
No
Yes
No
Pre trend
No
No
No
No
Yes
R-squared
0.215
0.221
0.223
0.266
0.223
N
29,596
29,596
29,596
28,076
29,596
Pre-1942 Mean
.174
.174
.174
.179
.174
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to
1970. The variable BRP equals 1 for 291 BRP books in the fields of chemistry and
mathematics. The control consists of 495 books in the Swiss National Library published in
Switzerland in the same fields. The variable post equals 1 for years after 1942. The variable
Mathematics equals 1 for books of mathematics. The variable decline in p measures the
difference between the original price that the German publisher changed in the United States
for book i and the price that the US publisher charged under the BRP divided by the price that
the German publisher had charged. Publisher fixed effects refer to US licensees for BRP
books, and to Swiss publishers for Swiss books. Book data are collected from the Report of
the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der
schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and
1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 5 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
Full Sample
(1)
BRP
BRP x post
Mathematics
BRP x Math x post
(2)
(3)
(4)
0.399*** 0.405*** 5.869*** 0.481***
(0.072) (0.074) (0.669) (0.087)
0.261*** 0.262*** 0.366*** 0.176*
(0.092) (0.091) (0.106) (0.091)
0.018
0.020
-0.048
0.018
(0.032) (0.032) (0.052) (0.033)
0.982** 0.993** 0.736* 0.983**
(0.403) (0.393) (0.366) (0.403)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Sample w/ price
info
(5)
1.983***
(0.664)
0.359***
(0.105)
-0.043
(0.051)
0.716*
(0.365)
Yes
Yes
Citation Year FE
Publication Year
FE
Language FE
No
Yes
Yes
No
Yes
Publisher FE
No
No
Yes
No
Yes
Pre-Trend
No
No
No
Yes
No
R-squared
0.215
0.216
0.260
0.216
0.260
N
29,971
29,971
28,451
29,971
28,076
Pre-1942 Mean
.174
.174
.179
.174
.179
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to
1970. The variable BRP equals 1 for 291 BRP books in the fields of chemistry and
mathematics. The control consists of 495 books in the Swiss National Library published in
Switzerland in the same fields. The variable post equals 1 for years after 1942. The variable
Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to US licensees
for BRP books, and to Swiss publishers for Swiss books. Book data are collected from the
Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches
Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols.
1921-1939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 6 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
(1)
BRP
(2)
(3)
0.282** 0.293** 4.290***
(0.112)
(0.113)
(0.733)
BRP x post
0.013
0.012
0.005
(0.129)
(0.131)
(0.135)
Decline in p
0.374
0.355
0.440
(0.412)
(0.409)
(0.644)
BRP x Decline in p x post
0.747
0.757
0.820
(0.478)
(0.480)
(0.587)
Mathematics
-0.012
-0.009
-0.010
(0.046)
(0.046)
(0.070)
BRP x math x Decline in p x post
3.844** 3.853*** 3.822***
(1.392)
(1.386)
(1.277)
Citation Year FE
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Language FE
No
Yes
Yes
Publisher FE
No
No
Yes
Pre-Trend
No
No
No
R-squared
0.254
0.255
0.286
N
29,596
29,596
28,076
Pre-1942 Mean
.174
.174
.179
Standard errors are clustered at the year of publication level
*** p<0.01, ** p<0.05, * p<0.1
(4)
0.358***
(0.104)
-0.059
(0.113)
0.348
(0.428)
0.750
(0.487)
-0.013
(0.047)
3.857***
(1.391)
Yes
Yes
No
No
Yes
0.256
29,596
.174
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to
1970. The variable BRP equals 1 for 291 BRP books in the fields of chemistry and
mathematics. The control consists of 495 books in the Swiss National Library published in
Switzerland in the same fields. The variable post equals 1 for years after 1942. The variable
Mathematics equals 1 for books of mathematics. The variable decline in p measures the
difference between the original price that the German publisher changed in the United States
for book i and the price that the US publisher charged under the BRP divided by the price that
the German publisher had charged. Publisher fixed effects refer to US licensees for BRP
books, and to Swiss publishers for Swiss books. Book data are collected from the Report of
the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der
schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and
1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 7 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
BRP
BRP x post
US Emigre
US emigre x BRP x post
(1)
(2)
(3)
(4)
(5)
(6)
0.212***
(0.048)
1.233***
(0.100)
-0.034
(0.086)
0.932**
(0.406)
0.244***
(0.049)
1.245***
(0.100)
-0.004
(0.087)
0.886**
(0.407)
5.885***
(0.838)
1.370***
(0.103)
-0.636***
(0.173)
0.422
(0.330)
0.207***
(0.048)
1.041***
(0.094)
0.232***
(0.048)
1.051***
(0.094)
4.993***
(0.825)
1.137***
(0.099)
0.071
(0.086)
2.113***
(0.396)
0.093
(0.087)
2.079***
(0.396)
-0.301*
(0.156)
1.965***
(0.399)
Yes
Yes
No
No
0.230
8,069
0.511
Yes
Yes
Yes
No
0.232
8,069
0.511
Yes
Yes
Yes
Yes
0.321
7,499
0.540
Emigre
Emigre x BRP x post
Citation Year FE
Publication Year FE
Language FE
Publisher FE
R-squared
N
Pre-42 mean
Yes
Yes
No
No
0.207
8,069
0.511
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
0.209
0.308
8,069
7,499
0.511
0.540
Robust standard errors in parentheses
*** p<0.01, ** p<0.05, * p<0.1
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The variable BRP equals 1 for 60 BRP books in mathematics.
The control consists of 495 books in the Swiss National Library published in Switzerland in the same fields. The variable post equals 1 for years after 1942.
The variable US Emigre equals 1 for 7 books published by authors who migrated to the US during their career. The variable Emigre equals 1 for 14 books
published by authors who migrated during their career. Publisher fixed effects refer to US licensees for BRP books, and to Swiss publishers for Swiss books.
Book data are collected from the Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen oder
die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 8 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
(1)
English
English x post
math
English x math x post
p decline
English x p decline x post
(2)
(5)
(6)
(3)
-0.191*** -0.190*** -0.191*** -0.190*** -0.192***
(0.028)
(0.030)
(0.028)
(0.030)
(0.028)
0.074** 0.072**
0.020
0.011
-0.072*
(0.034)
(0.036)
(0.033)
(0.034)
(0.038)
0.453*** 0.230*** 0.340*** 0.101** 0.432***
(0.032)
(0.032)
(0.036)
(0.039)
(0.031)
0.272*** 0.308***
(0.061)
(0.058)
0.764***
(0.057)
0.564***
(0.097)
English x p decline x math x post
Citation Year FE
Publication Year FE
Language FE
Publisher FE
Linear Pre-Trend
Flex. Pre-Trend
R-squared
N
Mean of Dep. Var.
Yes
Yes
Yes
No
No
No
0.083
19,136
0.464
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
No
No
No
No
No
No
No
No
0.123
0.085
0.125
0.105
19,004
19,136
19,004
18,442
0.465
0.464
0.465
0.474
Robust standard errors in parentheses
*** p<0.01, ** p<0.05, * p<0.1
(4)
(7)
(8)
-0.191*** -0.192*** -0.191***
(0.030)
(0.028)
(0.029)
-0.080** -0.062*
-0.071*
(0.039)
(0.038)
(0.039)
0.280*** 0.251*** 0.169***
(0.032)
(0.031)
(0.034)
0.630*** 0.772*** 0.704***
(0.064)
(0.058)
(0.064)
0.589*** 0.167* 0.255***
(0.094)
(0.092)
(0.092)
1.620*** 1.329***
(0.200)
(0.185)
Yes
Yes
Yes
Yes
No
No
0.136
18,310
0.476
Yes
Yes
Yes
No
No
No
0.114
18,442
0.474
Yes
Yes
Yes
Yes
No
No
0.142
18,310
0.476
Notes: The dependent variable counts citations to book i in year t and language l, for years from 1920 to 1970, to 236 books in chemistry and 55 books in
mathematics licensed to US publishers under the BRP. The variable English equals 1 for English-language citations. The variable post equals 1 for years
after 1942. The variable math equals 1 for mathematics books. The variable decline in p measures the difference between the original price that the German
publisher changed in the United States for book i and the price that the US publisher charged under the BRP divided by the price that the German publisher
had charged. Publisher fixed effects refer to US licensees for BRP books, and to Swiss publishers for Swiss books. Book data are collected from the Report of
the Alien Property Custodian (1942). Citations data are collected from Google Scholar (http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 9 – OLS, DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
BRP
BRP x post
(1)
BRP vs.
Swiss
(2)
BRP vs.
Swiss
0.363*
(0.177)
0.675
(0.393)
-0.480
(0.320)
0.676
(0.417)
(3)
German
vs. Swiss
(4)
German
vs. Swiss
(5)
BRP vs.
German
(6)
BRP vs.
German
0.187
(0.148)
0.668
(0.423)
0.040
(0.330)
0.675
(0.440)
German
0.161**
-0.114
(0.064)
(0.073)
German x post
0.146
0.119
(0.110)
(0.111)
Mathematics
0.061
0.092*
0.055
0.088*
-0.008
(0.040) (0.045)
(0.038)
(0.046)
(0.179)
Citat. year FE
Yes
Yes
Yes
Yes
Yes
Publ. year FE
Yes
Yes
Yes
Yes
Yes
Language FE
No
Yes
No
Yes
No
Publisher FE
No
Yes
No
Yes
No
R-squared
0.089
0.152
0.052
0.128
0.315
N
20,290
18,836
22,196
20,660
2,341
Pre-42 mean
.069
.067
.082
.081
.237
Standard errors are clustered at the year of publication level
*** p<0.01, ** p<0.05, * p<0.1
0.129
(0.220)
Yes
Yes
Yes
Yes
0.404
2,259
.242
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970.
In the sample “BRP vs. Swiss” the variable BRP equals 1 for 11 BRP books in the Swiss
National Library published in Germany in the fields of chemistry and mathematics, and the
control consists of 495 books in the Swiss National Library published in Switzerland in the
same fields. In the sample “German vs. Swiss” the variable German equals 1 for 55 books in
the Swiss National Library published in Germany in the fields of chemistry and mathematics,
and the control consists of 495 books in the Swiss National Library published in Switzerland in
the same fields. In the sample “BRP vs. German” the variable BRP equals 1 for 11 BRP books
in the Swiss National Library published in Germany in the fields of chemistry and mathematics,
and the control consists of 44 books in the Swiss National Library published in German in the
same fields and not subject to the BRP. The variable post equals 1 for years after 1942. The
variable Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to US
licensees for BRP books, and to Swiss publishers for Swiss books. Book data are collected
from the Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches
Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 19211939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
TABLE 10– OLS MATCHED SAMPLE,
DEPENDENT VARIABLE IS CITATIONS PER BOOK AND YEAR
BRP
(1)
(2)
0.475***
(0.136)
0.560***
(0.136)
6.481***
(0.124)
0.587***
(0.132)
(3)
(4)
0.320*
9.148***
(0.162)
(0.744)
BRP x post
0.126
0.114
(0.159)
(0.155)
Decline in p
0.552
0.077
(0.382)
(0.555)
BRP x Decline in p x post
1.391***
1.543***
(0.493)
(0.547)
Mathematics
0.649**
0.375
0.650**
0.463*
(0.254)
(0.254)
(0.242)
(0.254)
Citation Year FE
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Language FE
No
Yes
No
Yes
Publisher FE
No
Yes
No
Yes
Pre-Trend
No
No
No
No
R-squared
0.143
0.210
0.275
0.327
N
10,142
9,695
10,112
9,665
Pre-1942 Mean
.417
.436
.417
.436
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to
1970. The variable BRP equals 1 for 205 BRP books in the fields of chemistry and
mathematics. The control consists of 69 books in the Swiss National Library published in
Switzerland in the same fields. The control does not include dissertations and theses. The
sample is obtained using a Mahalanobis matching procedure based on year of publication,
field, language and finer subjects. The variable post equals 1 for years after 1942. The
variable Mathematics equals 1 for books of mathematics. The variable decline in p measures
the difference between the original price that the German publisher changed in the United
States for book i and the price that the US publisher charged under the BRP divided by the
price that the German publisher had charged. Publisher fixed effects refer to US licensees for
BRP books, and to Swiss publishers for Swiss books. Book data are collected from the Report
of the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der
schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and
1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
!
APPENDIX
APPENDIX FIGURE A1 – DISTRIBUTION OF PRE-1942 CITATIONS
Notes: Citations to 291 German BRP books in chemistry and mathematics and 495
Swiss books in the same fields. BRP books are collected from the Report of the
Alien Property Custodian (1942), and Swiss books are from Katalog.
Systematisches Verzeichnis der schweizerischen oder die Schweiz betreffenden
Veroffentlichungen (vols. 1921-1939 and 1931-1940). To collect citations we
accessed Google Scholar (http://scholar.google.com), accessed July 1st-September
25th, 2014.
APPENDIX FIGURE A2 – CITATIONS PER YEAR
Notes: Citations per year for 454 BRP books in various fields that were published in
Germany between 1920 and 1944 and subject to BRP, and to 495 Swiss books in
chemistry and mathematics in the Swiss National Library. To collect citations to
these books we accessed Google Scholar (http://scholar.google.com) between July
1st and September 25th, 2014.
!
!
APPENDIX FIGURE A3A –CITATIONS TO MODERNE ALGEBRA BY B. L. VAN DER
WAERDEN
Notes: The figure shows the location of citations to Moderne Algebra by Bartel L.
van der Waerden (1931). Green pins denote citations preceding 1942, red dots
denote citations between 1942 and 1970. Citations data are collected from Google
Scholar (http://scholar.google.com), accessed July 1st-September 25th, 2014.
APPENDIX FIGURE A3B– CITATIONS TO RICHTUNGSFELDER UND FERNPARALLELISMUS
IN N-DIMENSIONALEN MANNIGFALTIGKEITEN BY EDUARD STIEFEL
Notes: The figure shows the location of citations to Richtungsfelder und
Fernparallelismus in n-dimensionalen Mannigfaltigkeiten by Eduard Stiefel (1935).
Green pins denote citations preceding 1942, red dots denote citations between 1942
and
1970.
Citations
data
are
collected
from
Google
Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
APPENDIX FIGURE A3C –CITATIONS TO TOPOLOGIE BY PAUL ALEXANDROFF
AND HEINZ TOPF
Notes: The figure shows the location of citations to Topologie by Paul Alexandroff
and Heinz Topf (1935). Green pins denote citations preceding 1942, red dots denote
citations between 1942 and 1970. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
APPENDIX FIGURE A3D – CITATIONS TO DAS RANDVERHALTEN DER ABLEITUNG DER
ABBILDUNGSFUNKTION BEI KONFORMER ABBILDUNG BY STEPHAN E. WARSCHAWSKI
Notes: The figure shows the location of citations to Das Randverhalten der Ableitung
der Abbildungsfunktion bei konformer Abbildung by Stephan E. Warschawski (1932).
Green pins denote citations preceding 1942, red dots denote citations between 1942
and
1970.
Citations
data
are
collected
from
Google
Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014.
FIGURE A4 – AVERAGE CITATIONS PER YEAR IN ENGLISH LANGUAGE, CHEMISTRY
(TOP PANEL) AND MATHEMATICS (BOTTOM PANEL)
Notes: Citations per year in English language and in other languages for 236
books in chemistry (top panel) and 55 books in mathematics (bottom panel) in
the Swiss National Library, published in Germany subject to BRP. To collect
citations
to
these
books
we
accessed
Google
Scholar
st
th
(http://scholar.google.com) between July 1 and September 25 , 2014.
APPENDIX FIGURE A5 – AVERAGE CITATIONS PER YEAR –BOOKS IN SWISS “KATALOG”
Notes: Citations per year for 11 books in chemistry and mathematics in the
National Swiss Library published in Germany and subject to BRP, and to 495 Swiss
books in chemistry and mathematics. To collect citations to these books we
accessed Google Scholar (http://scholar.google.com) between July 1st and
September 25th, 2014.
APPENDIX FIGURE A6 – AVERAGE CITATIONS PER YEAR – BOOKS IN SWISS “KATALOG”
Notes: Citations per year for 55 books in chemistry and mathematics in the Swiss
National Library published in Germany, and to 495 Swiss books in chemistry and
mathematics. To collect citations to these books we accessed Google Scholar
(http://scholar.google.com) between July 1st and September 25th, 2014.
APPENDIX TABLE A1 – PUBLISHERS OF SWISS BOOKS
Publisher
Dissertations
Theses
ETH
Orell Fussli
Springer
Teubner
Thieme
Akadem. Verlagsg.
Borntraeger
Haupt
Payot
Enke
Rascher
Rouge
de Gruyter
Hermann
Blanchard
Huber
Steinkopff
Wepf
Birkhauser
Deuticke
Francke
Habilitationsschr
Habilitscher
Impr. Reunies
Kant
La Concorde
Vieweg
Winter
Other
N
875
407
370
27
20
8
8
7
7
6
6
5
5
5
5
4
3
3
3
3
2
2
2
2
2
2
2
2
2
2
28
Mathematics
All
Final Sample
119
31
41
17
28
19
27
9
17
0
8
0
0
0
2
0
0
0
1
1
4
0
0
0
3
2
5
3
5
0
4
0
3
0
3
1
0
0
3
1
2
2
0
0
2
0
2
2
2
2
0
0
2
0
2
1
0
0
0
0
23
9
All
756
366
342
0
3
0
8
5
7
5
2
5
2
0
0
0
0
0
3
0
0
2
0
0
0
2
0
0
2
2
5
Chemistry
Final Sample
169
86
93
0
0
0
0
0
0
1
1
0
1
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
2
Notes: List of publishers of 2,130 books in the Swiss National Library in the fields of chemistry
and mathematics. “Others” include 28 publishers publishing 28 books (9 in the final sample of
mathematics and 2 in chemistry). Data is collected from Katalog…. Systematisches Verzeichnis
der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and
1931-1940), Bern, H. Huber.
APPENDIX TABLE A2 – ORIGINAL PUBLISHERS OF BOOKS UNDER THE BOOK REPUBLICATION PROGRAM
Publisher
Springer
Akadem. Verlagsg.
Steinkopff
Enke
Barth
Hirzel
Borntraeger
Thieme
de Gruyter
Oldenbourg
Teubner
Knapp
Lehmann
Vieweg
Philosophical Library
Deuticke
Spamer
Voss
Others
Full sample
Mathematics
Chemistry
N
Original p
BRP p
N
Original p
BRP p
N
Original p
BRP p
233
76
29
27
26
15
11
11
11
9
8
6
5
5
4
3
3
3
46
34.86
26.11
83.33
8.48
13.48
10.01
21.65
53.51
123.70
5.79
6.51
8.45
12.91
33.15
3.34
33.17
38.40
11.00
17.52
19.03
6.57
7.96
9.83
8.86
15.55
30.89
40.28
5.07
6.00
7.00
10.60
21.97
3.25
20.27
35.45
7.80
35
4
2
0
3
1
1
0
1
2
4
0
0
0
0
0
0
0
2
10.49
8.79
4.30
-12.25
4.60
8.00
-12.65
4.90
6.10
--------
6.66
7.66
3.75
-9.67
3.85
5.75
-11.50
4.83
4.99
--------
87
42
14
19
12
4
7
7
5
0
1
5
4
3
3
1
2
3
17
67.55
35.51
10.47
8.66
17.50
21.27
14.13
77.00
255.61
-6.80
8.58
14.20
37.92
3.65
70.72
51.00
11.00
29.13
21.32
6.74
7.81
12.53
17.19
12.94
42.34
74.79
-6.50
7.20
11.31
26.25
3.00
40.00
46.58
7.80
Notes: List of the original publishers of BRP books. The “full” sample contains all 535 listed BRP books. The “mathematics” and “chemistry” samples
contains 55 books in mathematics and 236 books in chemistry for which we collect citations data. “Others” include 38 publishers publishing a total of 46
books (17 in the final sample of chemistry and 2 in the final sample of mathematics). BRP books are collected from the Report of the Alien Property
Custodian (1942).
APPENDIX TABLE A3 – SUBJECTS OF BOOKS UNDER THE “BOOK REPUBLICATION PROGRAM”
Subject
Aeronautics
Biology
Botany
Chemistry
Engineering
History
Language
Literature
Materials
Mathematics
Medicine
Metallurgy
Meteorology
Pharmacology
Physics
Telecommunications
N
4
15
3
275
91
1
6
1
50
63
27
1
4
2
187
6
Notes: List of subject classes for 535 BRP books.
199 out of 535 books are assigned to more than on
subject class. BRP books are collected from the
Report of the Alien Property Custodian (1942).
!
!
APPENDIX TABLE A4 – AVERAGE CITATIONS FOR BRP BOOKS
BRP books
w. price data
w/o price data
Difference
Pre-1942
Post-1942
Difference
0.212
(0.752)
0.551
(1.251)
0.000
(0.000)
0.551
(0.560)
0.498
(1.547)
0.968
(2.205)
0.338
(0.808)
0.630***
(0.115)
0.665***
(0.090)
0.417***
(0.055)
0.338
(0.362)
0.079
(0.919)
Notes: Means and standard deviations (in parentheses) of citations per year to 278 BRP books in the
fields of chemistry and mathematics with price data, and 13 BRP books in the same fields with
missing price data. BRP books are collected from the Report of the Alien Property Custodian (1942).
Citations data are collected from Google Scholar (http://scholar.google.com), accessed July 1stSeptember
25th,
201
APPENDIX TABLE A5 – ÉMIGRÉ AUTHORS
Name
Cohn-Vossen
Courant
Frank
Herzberger
Nr. of Books
Stefan
1
Richard
2
Philipp
1
Max
1
von Mises
von
Neumann
Nevanlinna
Polya
Szego
Richard
Johann
1
1
Country (year) of emigration
Switzerland (1933), USSR (1935)
UK (1933), USA (1934)
USA (1938)
Netherlands (1934), UK (1935), USA
(1935)
USA (1939)
USA (1933)
Rolf
George
Gabor
1
1
1
Switzerland (1947)
USA (1940)
USA (1934)
Dismissed
Yes
Yes
No
Yes
No
No
No
No
No
Notes: List of authors of BRP books in mathematics who migrated during their career. Information on
migration from Strauss et al. (1983) and the Mathematics Genealogy Project, accessed February 1st-14th at
http://genealogy.math.ndsu.nodak.edu.
APPENDIX TABLE A6 – BOOKS BY ÉMIGRÉ AUTHORS
Title
Methoden der mathematischen Physik
Strahlenoptik
Anschauliche Geometrie
Mathematische Grundlagen der
Quantenmechanik
Eindeutige analytische Funktionen
Differenzrechnung
Aufgaben und Lehrsatze aus der Analysis
Author
Publication
Year
Citations
Original
Price
Reproduction
Courant R.; Hilbert
Herzberger M.
Hilbert D.; CohnVossen
Neumann J.
1931
1931
1932
Nevanlinna R.
Norlund N.
Polya G.; Szego G.
US
Emigre
Decline
258
2
42
28.24
7.75
10.32
14
6.5
3.5
0.504
0.161
0.661
Yes
Yes
1932
56
7.85
3.5
0.554
Yes
1936
1924
1925
293
0
39
11.75
10.8
14.4
9.65
10.8
6
0.179
0.000
0.583
Yes
Notes: List of BRP books whose authors migrated during their career. Book data are collected from the Report of the Alien Property Custodian (1942).
Information on migration from Strauss et al. (1983) and the Mathematics Genealogy Project, accessed February 1st-14th at
http://genealogy.math.ndsu.nodak.edu.
APPENDIX TABLE A7 – OLS, DEPENDENT VARIABLE IS CITATIONS PER YEAR
(1)
BRP
0.387***
(0.062)
0.408***
(0.066)
(2)
(3)
(4)
0.404***
0.404***
2.046***
(0.068)
(0.069)
(0.411)
BRP x post
0.428***
0.429***
0.454***
(0.069)
(0.069)
(0.072)
Mathematics
0.298**
0.304**
0.223*
(0.115)
(0.116)
(0.109)
Citation Year FE
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Language FE
No
No
Yes
Yes
Publisher FE
No
No
No
Yes
Pre-Trend
No
No
No
No
R-squared
0.108
0.114
0.115
0.149
N
35,260
35,260
35,260
33,740
Pre-1942 Mean
.196
.196
.196
.202
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
(5)
0.493***
(0.071)
0.339***
(0.052)
0.299**
(0.116)
Yes
Yes
No
No
Yes
0.115
35,260
.196
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The
variable BRP equals 1 for 454 BRP books in various fields. The control consists of 495 books in the
Swiss National Library published in Switzerland in the same fields. The variable post equals 1 for
years after 1942. The variable Mathematics equals 1 for books of mathematics. Publisher fixed
effects refer to U.S. licensees for BRP books, and to Swiss publishers for Swiss books. Book data are
collected from the Report of the Alien Property Custodian (1942) and from Katalog….
Systematisches Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen
(vols. 1921-1939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com),
accessed
July
1st-September
25th,
2014.
APPENDIX TABLE A8 – OLS, DEPENDENT VARIABLE IS CITATIONS PER YEAR
BRP
(1)
(2)
(3)
-0.254*
(0.130)
0.501***
(0.099)
1.703***
(0.374)
0.542***
(0.107)
-0.133
(0.131)
0.379***
(0.079)
(4)
-0.464**
(0.174)
0.042
(0.125)
0.504
(0.384)
1.565***
(0.447)
0.273**
0.157
0.273**
0.255**
(0.114)
(0.103)
(0.114)
(0.106)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
No
No
Yes
No
No
Yes
Yes
Yes
Yes
No
No
Yes
No
0.142
0.198
0.143
0.226
29,971
28,451
29,971
29,596
.174
.179
.174
.174
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
BRP x post
Decline in p
BRP x Decline in p x post
Mathematics
Citation Year FE
Publication Year FE
Language FE
Publisher FE
German Publisher
Pre-Trend
R-squared
N
Pre-1942 Mean
(5)
(6)
4.814***
(0.656)
0.012
(0.131)
-0.095
(0.530)
1.790***
(0.509)
0.186*
(0.103)
Yes
Yes
Yes
Yes
Yes
No
0.271
28,076
.179
-0.399**
(0.144)
-0.055
(0.112)
0.474
(0.398)
1.575***
(0.452)
0.256**
(0.106)
Yes
Yes
No
No
Yes
Yes
0.228
29,596
.174
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The variable BRP equals 1 for 291 BRP books in the fields of
chemistry and mathematics. The control consists of 495 books in the Swiss National Library published in Switzerland in the same fields. The variable post
equals 1 for years after 1942. The variable Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to U.S. licensees for BRP books, and
to Swiss publishers for Swiss books. Book data are collected from the Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches
Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber. Citations data are
collected from Google Scholar (http://scholar.google.com), accessed July 1st-September 25th, 2014.
!
!
APPENDIX TABLE A9 – OLS, DEPENDENT VARIABLE IS CITATIONS PER YEAR
BRP
BRP x post
Mathematics
BRP x Mathematics x post
Decline in p
Full Sample
(3)
(1)
(2)
-34.391
(23.592)
35.287
(23.638)
0.285**
(0.114)
-6.603
(20.767)
7.263
(20.783)
0.019
(0.033)
0.982**
(0.403)
-11.031
(20.006)
11.347
(20.013)
0.268**
(0.107)
(4)
-6.356
(19.438)
6.652
(19.445)
-0.012
(0.047)
0.381
(0.411)
BRP x Decline in p x post
0.741
(0.475)
BRP x Mathematics x Decline in p x post
3.843**
(1.392)
Citation Year FE
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Linear Pre-Trend
Yes
Yes
Yes
Yes
R-squared
0.142
0.218
0.225
0.258
N
29,971
29,971
29,596
29,596
Pre-1942 Mean
.174
.174
.174
.174
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
w/o Dissertations
(5)
(6)
-34.391
(23.592)
35.287
(23.638)
0.285**
(0.114)
0.476
(0.380)
1.554***
(0.441)
-11.031
(20.006)
11.347
(20.013)
0.268**
(0.107)
0.476
(0.380)
1.554***
(0.441)
Yes
Yes
Yes
0.142
29,971
.174
Yes
Yes
Yes
0.225
29,596
.174
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The variable BRP equals 1 for 291 BRP books in the fields of
chemistry and mathematics. The control consists of 495 books in the Swiss National Library published in Switzerland in the same fields. The variable post
equals 1 for years after 1942. The variable Mathematics equals 1 for books of mathematics. The variable decline in p measures the difference between the
original price that the German publisher changed in the US for book i and the price that the US publisher charged under the BRP divided by the price that the
German publisher had charged. Publisher fixed effects refer to U.S. licensees for BRP books, and to Swiss publishers for Swiss books. Book data are
collected from the Report of the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen oder die Schweiz
betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber. Citations data are collected from Google Scholar
(http://scholar.google.com), accessed July 1st-September 25th, 2014. from Google Scholar (http://scholar.google.com), accessed July 1st-September 25th,
2014.
APPENDIX TABLE A10 – OLS, DEPENDENT VARIABLE IS CITATIONS PER YEAR – EXCLUDING
DISSERTATIONS
(1)
BRP
0.347***
(0.075)
0.500***
(0.101)
(2)
(3)
(4)
0.375***
0.369***
1.770***
(0.090)
(0.090)
(0.397)
BRP x post
0.534***
0.535***
0.566***
(0.110)
(0.111)
(0.117)
Mathematics
0.392**
0.403**
0.270
(0.174)
(0.174)
(0.202)
Citation Year FE
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Language FE
No
No
Yes
Yes
Publisher FE
No
No
No
Yes
Pre-Trend
No
No
No
No
R-squared
0.112
0.123
0.124
0.180
N
17,576
17,576
17,576
16,056
Pre-1942 Mean
.300
.300
.300
.328
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
(5)
0.519***
(0.112)
0.390***
(0.085)
0.393**
(0.175)
Yes
Yes
No
No
Yes
0.123
17,576
.300
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The
variable BRP equals 1 for 291 BRP books in the fields of chemistry and mathematics. The control
consists of 192 books in the Swiss National Library published in Switzerland in the same fields. The
control does not include dissertations and theses. The variable post equals 1 for years after 1942. The
variable Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to U.S. licensees
for BRP books, and to Swiss publishers for Swiss books. Book data are collected from the Report of
the Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der
schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940),
Bern, H. Huber. Citations data are collected from Google Scholar (http://scholar.google.com),
accessed July 1st-September 25th, 2014. from Google Scholar (http://scholar.google.com), accessed
July 1st-September 25th, 2014.
!
!
APPENDIX TABLE A11 – OLS, DEPENDENT VARIABLE IS CITATIONS PER YEAR – EXCLUDING
DISSERTATIONS
(1)
BRP
(2)
(3)
(4)
0.192* 0.225** 0.215* 4.060***
(0.112) (0.109) (0.111) (0.687)
BRP x post
0.052
0.083
0.081
0.046
(0.125) (0.127) (0.129) (0.134)
Decline in p
0.591
0.567
0.563
0.049
(0.394) (0.379) (0.375) (0.537)
BRP x Decline in p x post 1.509*** 1.511*** 1.520*** 1.747***
(0.453) (0.443) (0.445) (0.505)
Mathematics
0.374** 0.387**
0.332
(0.165) (0.166) (0.202)
Citation Year FE
Yes
Yes
Yes
Yes
Publication Year FE
Yes
Yes
Yes
Yes
Language FE
No
No
Yes
Yes
Publisher FE
No
No
No
Yes
Pre-Trend
No
No
No
No
R-squared
0.229
0.237
0.239
0.286
N
17,201
17,201
17,201
15,681
Pre-1942 Mean
.300
.300
.300
.328
Standard errors are clustered at the year of publication level
*** p<0.01, ** p<0.05, * p<0.1
(5)
0.343***
(0.111)
-0.030
(0.120)
0.533
(0.393)
1.526***
(0.448)
0.375**
(0.166)
Yes
Yes
No
No
Yes
0.239
17,201
.300
Notes: The dependent variable counts citations to book i in year t, for years from 1920 to 1970. The
variable BRP equals 1 for 291 BRP books in the fields of chemistry and mathematics. The control
consists of 192 books in the Swiss National Library published in Switzerland in the same fields. The
control does not include dissertations and theses. The variable post equals 1 for years after 1942. The
variable Mathematics equals 1 for books of mathematics. The variable decline in p measures the
difference between the original price that the German publisher changed in the United States for book
i and the price that the US publisher charged under the BRP divided by the price that the German
publisher had charged. Publisher fixed effects refer to U.S. licensees for BRP books, and to Swiss
publishers for Swiss books. Book data are collected from the Report of the Alien Property Custodian
(1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen oder die Schweiz
betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber. Citations data are
collected from Google Scholar (http://scholar.google.com), accessed July 1st-September 25th, 2014.
APPENDIX TABLE A12 – BOOKS LISTED IN THE NATIONAL SWISS LIBRARY CATALOG SUBJECT TO THE BRP
Publisher
Licensee
Year
Field
Original
price
Reproduction
price
Topologie
Springer
J.W. Edwards
1935
Mathematics
$18.75
$12.00
Grundlagen der Mathematik
Vorlesungen uber allgemeine
Funktionentheorie und
elliptische Funktionen
Lehrbuch der organischen
Chemie
Springer
J.W. Edwards
1934
Mathematics
$32.65
$25.60
Springer
Interscience
Publishers
1922
Mathematics
$13.92
$7.50
Thieme
Elsevier
1942
Chemistry
$9.07
$3.75
Authors
Alexandroff, Paul
and Hopf, Heinz
Hilbert, David
Hurwitz, Adolf and
Courant, Richard
Karrer, Paul
Title
Kempf, Richard and
Kutter, Fritz
Schmelzpunkt-Tabellen zur
organischen Molekular-Analyse
Viewet
J. W. Edwards
1928
Chemistry
$27.50
$16.50
Polya, George and
Szego, Gabor
Aufgaben und Lehrsatze aus der
Analysis
Springer
Dover
Publications
1925
Mathematics
$14.40
$6.00
Rosenthaler,
Leopold
Toxikologische Mikroanalyse;
qualitative Mikrochemie der
Gifte u. a. gerichtlich-chemisch
wichtiger Stoffe
Borntraeger
J. W. Edwards
1935
Chemistry
$11.20
$9.50
Springer
Dover
Publications
1937
Mathematics
$6.60
$3.50
Borntraeger
J. W. Edwards
1933
Chemistry
$99.20
$61.50
Speiser, Andreas
Tschirch, Alexander
and Stark, Erich
Die Theorie der Gruppen von
endlicher Ordnung
Die Harse; die botanischen und
chemischen Grundlagen unserer
Kenntnisse uber die Bildung, die
Entwicklung und die
Zusammensetzung der
pflanzlichen Exkrete
Vogel, Hans
Tabellen der Zucker und ihrer
Derivate
Springer
J. W. Edwards
1931
Chemistry
$50.40
$13.50
Notes: BRP books in the Swiss National Library published in Germany. Two editions of the Lehrbuch der organischen Chemie by Paul Karrer, published in
1928 and 1937, are listed in the National Swiss Library catalog; they are counted as separate. Book data are collected from the Report of the Alien Property
Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and
1931-1940), Bern, H. Huber.
APPENDIX TABLE A13 – AVERAGE CITATIONS PER YEAR – MATCHED SAMPLE
1920-41
1942-1970
Difference
!
!
Full
Sample (N = 274)
!
!
0.1.112
(2.020)
1.033
(2.274)
0.133
(0.480)
0.900***
(0.051)
!
!
!
BRP
(N = 205)
!
!
!
Swiss
!
!
!
Difference
!
!
!
!
!
Chemistry
(N = 205)
0.417
(0.806)
0.564
(1.289)
0.084
(0.341)
0.480***
(0.050)
0.389***
(0.045)
0.469***
(0.061)
0.049***
(0.020)
0.419**
(0.097)
!
!
!
BRP
(N = 160)
1.208
(1.590)
0.796
(1.758)
0. 083
(0.359)
0.713***
(0.049)
!
!
!
!
!
!
!
!
!
Mathematics
0.454
(0.640)
0.614
(1.391)
0.062
(0.282)
0.552***
(0.065)
0.186***
(0.042)
0.183**
(0.056)
0.022***
(0.018)
0.161*
(0.094)
!
!
!
BRP
1.300
(2.893)
1.873
(3.417)
0.227
(0.639)
1.646***
(0.131)
!
!
!
!
!
!
!
0.314
(0.775)
0.412
(0.892)
0.137
(0.444)
0.275***
(0.066)
0.986***
(0.121)
1.461***
(0.178)
0.090
(0.048)
1.371***
(0.245)
!
Swiss
!
Difference
!
!
!
Swiss
!
Difference
Notes: Means and standard deviations (in parentheses) of citations per year to 274 BRP books in the
fields of chemistry and mathematics, and to 69 books in the Swiss National Library published in
Switzerland in the same fields. The sample is obtained using a Mahalanobis matching procedure based
on year of publication, field, language and finer subjects. Book data are collected from the Report of the
Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen
oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber.
Citations data are collected from Google Scholar (http://scholar.google.com), accessed July 1stSeptember 25th, 2014. from Google Scholar (http://scholar.google.com), accessed July 1st-September
25th,
2014.!
APPENDIX TABLE A14 – MOST EXPENSIVE BOOKS
Author
Title
City
Editor
Licensee
Publication
Year
Origina Reproductio
l price n price
Mathematics
Hilbert, D.
Die Differential und Integralgleichungen
der Mechanik und Physik
Grundlagen der Mathematik
Courant, R.
Methoden der mathematischen Physik
Berlin
Springer
Peters, J.
Eight-place table of trigonometric
functions
Berlin
Reichsamt fur
Landesaufnahme
J. W. Edwards
1939
$24.00
$20.00
Alexandroff,
P.
Topologie (Erster Band) (Grundlehren der
mathematischen Wissenschaften in
Einzeldarstellungen, Bd. 45)
Berlin
Springer
J.W. Edwards
1935
$18.75
$12.00
Frank, P.
Brauschweig
Vieweg & Sohn
Berlin
Springer
M. S.
Rosenberg
J. W. Edwards
Prof. R.
Courant
1930
$48.40
$27.50
1934
$32.65
$25.60
1931
$28.24
$14.00
Chemistry
Beilstein, F.
K.
Saccardo, P.
A.
$2,000.
00
$2,000.
00
Handbuch der organischen Chemie
Berlin
Springer
J.W. Edwards
1918
$400.00
Sylloge fungorum omnium hucusque
cognitorum... curante Alex
Napoli
Eredi Saccardo
J. W. Edwards
1881
Brauer, A.
Fortschritte in der anorganischchemischen Industrie
Berlin
Springer
J.W. Edwards
1921
$758.00
$330.00
Houben, J.
Fortschritte der Heilstoffchemie
Berlin
de Gruyter
J. W. Edwards
1926
$512.50
$250.00
Landolt, B.
Physikalisch-chemische Tabellen
Berlin
Springer
J. W. Edwards
1923
$365.00
$180.00
$200.00
Notes: Information on the 5 most expensive BRP books in the field of mathematics and the 5 most expensive BRP books in the field of chemistry. BRP books
data
are
collected
from
the
“Book
Republication
Program”
(Alien
Property
Custodian,
1942).
APPENDIX TABLE A15 – OLS, DEPENDENT VARIABLE IS LOG(CITATIONS PER YEAR)
Full Sample
(1)
BRP
BRP x post
Mathematics
(2)
(3)
(4)
(5)
2.011*** 2.007*** 1.998*** 9.626*** 2.293***
(0.216) (0.219) (0.229) (0.840) (0.306)
0.873*** 0.904*** 0.909*** 1.018*** 0.618**
(0.149) (0.150) (0.151) (0.170) (0.252)
0.468** 0.485**
0.176
0.469**
(0.206) (0.204) (0.194) (0.207)
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Sample w/ price
info
(6)
Citation Year FE
Publication Year
FE
Language FE
No
No
Yes
Yes
No
Publisher FE
No
No
No
Yes
No
R-squared
0.147
0.149
0.150
0.182
0.150
N
29,971
29,971
29,971
28,451
29,971
Pre-Trend
No
No
No
No
Yes
Standard errors are clustered at the year of publication level.
*** p<0.01, ** p<0.05, * p<0.1
8.951***
(0.821)
1.022***
(0.170)
0.163
(0.192)
Yes
Yes
Yes
Yes
0.185
28,076
No
Notes: The dependent variable is the natural logarithm of 0.00005 + counts citations to book i in year t,
for years from 1920 to 1970. The variable BRP equals 1 for 275 BRP books in the fields of chemistry
and mathematics. The control consists of 393 books in the Swiss National Library published in
Switzerland in the same fields. The variable post equals 1 for years after 1942. The variable
Mathematics equals 1 for books of mathematics. Publisher fixed effects refer to U.S. licensees for
BRP books, and to Swiss publishers for Swiss books. Book data are collected from the Report of the
Alien Property Custodian (1942) and from Katalog…. Systematisches Verzeichnis der schweizerischen
oder die Schweiz betreffenden Veröffentlichungen (vols. 1921-1939 and 1931-1940), Bern, H. Huber.
Citations data are collected from Google Scholar (http://scholar.google.com), accessed July 1stSeptember 25th, 2014. from Google Scholar (http://scholar.google.com), accessed July 1st-September
25th, 2014.
!