IS THERE C I T Y SIZE DISTRIBUTION FOR DENEIDPING COUNTRIES? by PETE33 SPENCE GUDSEON B .A. onou ours) , Victoria University of Manchester , 1965 Dip. i n Econ. Dev.., Victoria University of Manchester, MASTER OF ARTS i n t h e department Economics and Commerce @ PET^ SPEDTCEG U ~ E O N , 1968 SIMOK F'RAsm UNIVERSITY Dec ember , 1968 1967 D r . K . Okuda Senior Supervisor D r . D. Maki Examining Comr.'Littee --Dr.N. Robinson Examining Committee ABSTRACT The d i s t r i b u t i o n of c i t y s i z e s i n terms of population i n both underdeveloped c o u n t r i e s and developed c o u n t r i e s , has r e c e n t l y come under c l o s e examination by s p e c i a l i s t s i n many academic f i e l d s . The ad- v e n t of g e n e r a l systems theory has proved t o be an invaluable a n a l y t i c a l approach t o t h e study of c i t y s i z e d i s t r i b u t i o n s , i n t h a t it i n c o r p o r a t e s s t o c h a s t i c growth theory, and t h e concept of entropy. These two a s p e c t s of g e n e r a l systems theory have been very u s e f u l i n explaining some of t h e e m p i r i c a l r e g u l a r i t i e s observed of c i t y s i z e d i s t r i b u t i o n s , e s p e c i a l l y t.he log-normal ( o r rank-si ze ) d i s t r i b u t i o n . This essay p r i m a r i l y examines t h e v a r i o u s t h e o r i e s t h a t have been developed t o explain t h e rank-size d i s t r i b u t i o n of c i t i e s , and r e l a t e s t h e s e t h e o r i e s t o t h e g e n e r a l systems approach. It i s a l s o hypothesized ( i n a somewhat t e n t a t i v e f a s h i o n ) t h a t t h e log-normal c i t y s i z e d i s t r i b u t i o n i s an "optimum" equilibrium o r "steady-state" d i s t r i k b u t i o n toward which c i t y s i z e d i s t r i b u t i o n s t e n d under c e r t a i n l a r g e comp e t i t i v e environmental conditions. This essay i s not intended t o be an exhaustive study of t h e l i t e r a t u r e , and i n c o r p o r a t e s only a b r i e f excursion i n t o p o s s i b l e p o l i c y c o n s i d e r a t i o n s of t h e t h e o r e t i c a l and e m p i r i c a l f i n d i n g s on t h e c i t y s i z e d i s t r i b u t i o ~ si n developing and developed c o u n t r i e s . (iii)' TABLE OF CONTENTS Page ................................................ I. C i t y S i z e D i s t r i b u t i o n s and Developing Countries ..... I1 . C i t y S i z e D i s t r i b u t i o n and P a r e t o ' s Law .............. I11. Zipf and t h e Rank-Size Rule .......................... I V. ' C h r i s t a l l e r and t h e S i z e C l a s s e s of C i t i e s ........... The City-Size D i s t r i b u t i o n a s a S t o c h a s t i c Process ... V. VI. City-Size D i s t r i b u t i o n s and P o l i c y Consideration ..... V I I . City-Size D i s t r i b u t i o n s and General Systems Theory .... 1 I n d i a n City-Size D i s t r i b u t i o n ........................ IX . conclusion ........................................... References .................................................. Introduction 1 6 9 13 16 18 25 36 42 48 50 (iv) I LIST OF DIAGRAMS PAGE lc The log-normal (rank-size ) d i s t r i b u t i o n The p r j i a t e d i s t r i b u t i o n The i n t m n e d i a t e d i s t r i b u t i o n 2' P o s s i b l e e f f e c t s of a 3 P o s s i b l e e f f e c t s of r e s t r i c t i n g t h e s i z e of the 1 z . r g e ~ tc i t y . la lb .................... 7 r e d i s t r i b u t i o n p o l i c y . . . . . . 28 ... . .. .. . .... . ........ . . .. . .. 28 INTRODUCTION The existence of d i f f e r e n t s i z e d i s t r i b u t i o n s of c i t i e s i n b o t h developing and developed countries has long been recognized by students i n many d i s c i p l i n e s , and has r a i s e d some fundamental questions f o r planning i n underdeveloped countries. For example, i s t h e r e any s i g n i f i c a n c e i n t h e f a c t ' t h a t some c i t i e s have grown f a s t e r t h a n o t h e r c i t i e s ? t h e causes of t h i s growth? What a r e What are t h e problems associated with d i f f e r - e n t i a l growth and s i z e of c i t i e s ? Much of t h e work on urban problems has been done i n rel a t i o n t o regional development programming i n t h e United S t a t e s , and comparatively l i t t l e research has been undertaken on t h e f'undamental problems of defining an optimum s i z e ; d i s t r i b u t i o n of c i t i e s f o r developing countries. optimality? Is t h e r e indeed an optimum? What a r e t h e c r i t e r i a f o r 1% t h e r e an optimum with respect t o maximization of economic growth, o r i s it some broadly defined welfare optimum t h a t i s desired? Obviously t h e optinium s i z e d i s t r i b u t i o n of c i t i e s i n underdeveloped countries could be defined i n terms of economic, s o c i a l , p o l i t i c a l , o r any o t h e r c r i t e r i a , and t h e choice of optimum w i l l depend very much on t h e o b j e c t i v e f'unction of t h e planner and those of s o c i e t y a t l a r g e . It i s worthwhile a t t h e o u t s e t t o give some consideration t o t h e general problems of defining our c r i t e r i a f o r optimality. approach t h e problem from maay d i f f e r e n t angles; One can one can define an absolute l i m i t t o t h e s i z e of any one c i t y under d i f f e r e n t s e t s of i n i t i a l conditions and c o n s t r a i n t s o r one coclld search f o r an optimum f o r t h e whole range of c i t y s i z e s i n any m e country. Any c r i t e r i a f o r optimum population s i z e involves, imp l i c i t l y o r e x y l i c i t l y , two elements: f i r s t the normative element, which places a p o s i t i v e o r negative valuation on a p a r t i c u l a r situation; and second, a f a c t u a l element which has the force of a statement of empirical r e l a t i o n s h i p s between v a r i a t i o n i n c i t y s i z e and v a r i a t i o n i n the s i t u a t i o n i n question. One can a l s o a t t a c k t h i s problem from (1) the point of view of the t h e o r i s t of c i t y planning i n t e r e s t e d i n s e t t i n g general standards f o r the over-all planning of c i t i e s , or (2) determine a l i s t of s p e c i f i c c r i t e r i a f o r determining optimum c i t y s i z e , o r (3) examine each of the c r i t e r i a from the standpoint of observable r e l a t i o n s h i p between c i t y s i z e and the variables involved i n the c r i t e r i a . Consider f o r example t h a t a c r i t e r i o n of optimum c i t y s i z e i s t h a t a c i t y ' s s i z e should be t h a t which i s favorable t o the health of i t s population. Hence: Let good health = a p o s i t i v e value. Let. ill health = a negative value. IS t'nere some s i g n i f i c a n t c o r r e l a t i o n between c i t y s i z e and health? If there were no such correlation, there would obviously be no "most favorable" s i z e , i . e . no optimum. Clearly then, examining c i t y s i z e from the point of view of the c i t y planning t h e o r i s t provides only one i l l u s t r a t i o n of a procedure f o r v a l i d a t i n g the concept of optknun c i t y s i z e . H i s t o r i c a l l y the concept of optimm s i z e of c i t i e s has Un- d e r l a i n planning theory and practice, eithe'r i n e x p l i c i t or implicit f o m . Among the c r i t e r i a t h a t have been examined in r e l a t i o n t o the optimum c i t y s i z e i n both developed developing countries i s : (1) City s i z e and physical planning of c i t i e s w i t h respect t o the frequent demand t h a t c i t i e s be small enough t o enable ready access t o the countryside and a resonably moderate journey t o work., i . e . transporation problems, (2) City s i z e and health diseases, e t c . ) (3) City s i z e and public s a f e t y f i r e hazards, e t c ) . ( m o r t a l i t y r a t e s , incidence of .. (crime r a t e s , accident r a t e s , (4) City s i z e and municipal e f f i c i e n c y (highways, s a n i t a t i o n , public welfare, schools, e t c . ) . ( 5 ) City s i z e and education expenditures. ( 6 ) City s i z e and cost of l i v i n g . (7) City s i z e and public r e c r e a t i o n ( a c c e s s i b i l i t y t o parks, zoos, t h e a t r e s , e t c . ) . (8) City s i z e and r e t a i l f a c i l i t i e s . ( 9 ) City s i z e and churches and a s s o c i a t i o n s . (10) City s i z e .and family l i f e (degree of homeownership, divorce r a t e s , domestic f a c i l i t i e s , e t c , ) (11) City s i z e and miscellaneous psychological and s o c i a l chara c t e r i s t i c s of urban l i f e (provincialism, f r i e n d l i n e s s , s o c i a l contentment, community p a ~ t i c i p a t i o n ) . . It i s immediately apparent t h a t one could extend t h i s l i s t indefinately a t t h e r i s k of increasing the already considerable overlap i n the tyye of r e l a t i o n s h i p s , and r e a l i z i n g a t the same time t h a t t h e question of the casual significance of the r e l a t i o n s h i p s between c i t y s i z e and these phenomenesis subject t o serious problems of s t a t i s t i c a l i n t e r p r e t a t i o n . 1 A r a t h e r b i z a r r e example of planning optimality according t o a d e f i n i t e c r i t e r i o n i n advanced i n d u s t r i a l countries i s the idea t h a t c i t i e s should be small enough t o have a low prp3bability of nuclear des2 truction. A s a general statement it would be t r u e t o say t h a t i n the p a s t economists have not paid much a t t e n t i o n t o optimum c i t y s i z e , and even l e s s a t t e n t i o n t o optimum c i t y s i z e d i s t r i b u t i o n s . More recelri; r e - search on the r e l a t i o n s h i p of c i t y s i z e t o economic policy, e s p e c i a l l y publik investment decisions and growth theory i n r e l a t i o n t o urbanization and i n d u s t r i a l i z a t i o n i n unaerdeveloped countries and developed countries, has helped t o eliminate t h e i r shortcomings. 3 Yet t h e study of optimum c i t y s i z e d i s t r i b u t i o n s has been meagre t o say t h e l e a s t , u n t i l the advent of a general systems approach t o the study of c i t y s i z e d i s t r i b ~ t i o n s . This approach t o the study examines the r o l e , functions, and spatial d i s t r i b u t i o n of c i t i e s as a sub'system i n a whole i n t e g r a t e d system t o economic and s o c i a l development, and has been u s e f u l l y applied t o developed and underdeveloped countries a l i k e . 4 ' The m u l t i p l i c i t y of d i f f e r e n t c r i t e r i a f o r optimal c i t y s i z e o r c i t y s i z e d i s t r i b u t i o n s makes it impossible, i n my opinion, t o a r r i v e a t some meaningfuloverall c r i t e r i o n . conclle the d i f f e r e n t c r i t e r i a . It would be impossible t o r e - I n view of t h i s a deductive approach t o t h e general problem appears more reasonable. Can me a r r i v e a t any con- c h s ions from examination of the many d i f f e r e n t c i t y size distributions? causes underlying e x i s t i n g I s there a c i t y s i z e d i s t r i b u t i o n t h a t canes c l o s e s t t o an a c t u a l o r t h e o r e t i c a l optimum? Evidence suggests t h a t t h i s may be so, i n t h e form of t h e log-normal c i t y s i z e d i s t r i b u t i o n . Consequently much of t h i s essay w i l l be concerned with examination of the log-normal types of c i t y s i z e d i s t r i b u t i o n and t h e i r relevance t o t h e problem of an optimum c i t y s i z e d i s t r i b u t i o n . However be- f o r e t h i s i s dore one must examine t h e empirical evidence on e x i s t i n g d i s t r i b u t i o n s i n developing countries. I. --- CITY SIZE DL STRIBUTIONS AND DEVELOPING COUNTRIES .- --P Possibly the most complete and comprehensive empirical study of the c i t y s i z e distributions i n developed and developing countries i s t h a t by Berry, 5 who analyzed c i t y s i z e d i s t r i b u t i o n s and t h e i r r e l a - tionship t o l e v e l s of economic developzlent i n thirty-eight countries. He found t h a t the d i s t r i b u t i o n s f a l l i n t o two major categories, namely the Rank-Size Distribution 6 and the Primate Distribution. 7 The Rank-Size Distribution was revealed in both developed and underdeveloped countries when the cumulative frequency of c i t i e s with a population of greater than twenty thousand people was ranked against the s i z e of c i t y on a log-normal s c a l e , Thirteen of the t'nirty-eight Coun- t r i e s had log-normally d i s t r i b u t e d sizes. 8 ( See Diagram l a ) . The Primate Distribution which was c h a r a c t e r i s t i c of f i f t e e n out of t h i r t y - e i g h t countries examined, i s observed when a stratum of small towns and c i t i e s i s dominated by one or more very large c i t i e s and there a r e deficiencies . i n t h e number of c i t i e s of intermediate s i z e . gram l b ) 9 (See Dia- Berry's study tended t o support the hypothesis t h a t Primate City Distributions a r e associated with over-urbanization and superimposed colo n i a l economies i n underdeveloped countries o r with political-administrat i v e controls i n indigenous subsistence and peasant economies. Furthermore it has been argued t h a t primate c i t i e s have p a r a l y t i c e f f e c t s upon the development of s x a l l e r urban places and tend t o be p a r a s i t i c i n r e l a t i o n t o the remainder of t h e n a t i o n a l economy. Nine out of t h i r t y - e i g h t of the countries examined had d i s t r i b u t i o n s intermediate between t h e log-normal (rank-size) and the primate No.of C i t i e s The LOG-NORMAL (=-SIZE) DISTRIBUTION. a: b: c: d: United S t a t e s China Korea E l Salvador Size of City. (10,000 i n h a b i t a n t s ) . No.of Cities DIAGRAM l b 601I & 50. *5 4039- Tne PRIMATE DISITiiIBUTION. u a~ 3.6. % rl I a~ rd PI; ' 0 - a: a, S M -4 0 a *riA 0 'J% b: Thailand Denmark b u 0 1 , IC I 50 ' ze of City. (10,000 i n h a b i t a n t s ) loo DIAGRAM l c No.of C i t i e s 60 1 50 4t 30 The INTERMEDIATE DISTRIBUTION. - a: b: Portugal Australia c : England and Wales 2.0 to - 6.1 1- r 5 '0 50 A '00 Size of City. (10,000 i n h a b i t a n t s ) distribution. 10 ( See Diagram l c ) A s i g n i f i c a n t conclusion of Berry's study however was t h a t : Different c i t y s i z e d i s t r i b u t i o n s a r e i n no way r e l a t e d t o the r e l a t i v e economic development of countries. Rank-size i s not t h e culmination of a process i n which n a t i o n a l unity i s expressed i n a system of c i t i e s .ll I n order t o appreciate t h e significance of ~ e r r y ' sconclusions on the r e l a t i o n s h i p of c i t y s i z e d i s t r i b u t i o n t o l e v e l of economic development l2 and the r e l a t i o n t o the general problem of an optimal c i t y s i z e d i s t r i b u t i o n , one must examine the various t h e o r i e s attempting t o explain t h e empirical r e g u l a r i t i e s manifested i n t h e rank-size (log-normal) distribution. 11. CITY SIZE DISTRIBUTION AND PARETO' S LAW Among t h e f i r s t economists t o recognize c e r t a i n regulari t i e s i n t h e c i t y s i z e r e l a t i o n s h i p s was H. W. Singer, l3 who compared t h e c i t y s i z e d i s t r i b u t i o n s f o r seven countries with t h e Pareto type of i n come d i s t r i b u t i o n , and found them both t o be of a s i m i l a r shape. The Pareto curve i s of t h e form y = A a 4 o r y = Ax where x = income l e v e l . y =.number of persons with t h a t l e v e l of income o r over. I n logarithmic form, l o g y = l o g A - d l o g x, and t h e Pareto curve takes on a l i n e a r form t h a t can be conveniently p l o t t e d on a double log scale. Now - d i s t h e e l a s t i c i t y of t h e function of d i s t r i b u t i o n of incomes, t h e r e f o r e o( = -d log y d log and i s constant. : Hence can be i n t e r - p r e t e d a s t h e e l a s t i c i t y of decrease i n t h e number of persons whkn passing t o a higher income. By increasing t h e income x by dx = 1,000, from 10,000 t o 11,000, we g e t a r e l a t i v e decrease i n t h e number of persons by approximately dy = - Y Whereas, i f dx = 1,000 and x = 11,000 then g =- 6( . , y . & 61,000 . - 1,000 = -oC which i s l e s s i n terms of percentage 11 than t h e r e l a t i v e decrease obtained a t t h e t r a n s i t i o n from t h e income of 10,000 t o an income of 11,000. Therefore, t h e r e l a t i v e decrease (screening) in-,the number of persons a s t h e income increases i s smaller and smaller and - 10 diminishes i n proportion t o the income, therefore -4dx dy = Y X Hence, the advance t o a higher c l a s s of incomes i s e a s i e r f o r persons who have already reached a higher income than f o r persons with lower incomes. The reduction in the r e l a t i v e decrease of the number of persons, during t r a n s i t i o n t o higher and higher incomes, i n proportion t o t h e income, c o n s t i t u t e s the essence of P a r e t o ' s Law. 14 The Pareto formula has been given a probability i n t e r p r e t a t i o n by Champernowne, l5 We can regard the Pareto curve i n two ways, e i t h e r a s representing the exact number of persons of an income not small e r than x, or i n terms of the number of persons with an income smaller than ( o r not smaller than) i t s mean value (mathematical expectation). Con- sequently, according t o the Pareto formula, the mathematical expectation of t h e r e l a t i v e screening decreases i n proportion t o the income. The mat'n- ematical expectation of a persods being t r a n s f e r r e d t o higher classes of income w i l l , therefore, be proportional t o the given income, s i d e r t h e c i t y s i z e d i s t r i b u t i o n i n a s i m i l a r manner. We can con- For example, t h e mathematical expectation of a c i t y being t r a n s f e r r e d t o a higher c l a s s s i z e of c i t y (through growth of the c i t y i n terms of population), t i o n a l t o the given c i t y s i z e . i s propor- Thus one would expect, on average, the l a r g e s t c i t i e s t o grow a t a f a s t e r absolute r a t e than the smaller c i t i e s through t h i s screening process, and have a lower c l a s s mobility than c i t i e s of smaller s i z e . Chmpernowne has analyzed t h e development through t h e of t h e d i s t r i b u t i o n of incomes between certain.income ranges a s being a s t o c h a s t i c process, so t h a t the income of any individual i n any one year may - 11 $ depend on what it was i n the previous year and on a random process. From the r e g u l a r i t y t h a t Champernowne had established empirically, Pareto t r i e d t o derive a general sociological "law" which he regarded a s a "natu r a l lawff t h a t held f o r a l l times and a l l s o c i e t i e s . ~t would appear from t h i s "lawff, t h a t a11 s o c i a l reforms intended t o remove inequality in t h e d i s t r i b u t i o n of national income were doomed t o f a i l u r e from the o u t s e t , since the law of nature about t h e d i s t r i b u t i o n of income acted i n all conditions and the d i s t r i b u t i o n of income would always take t h e shape indicated by the formula he established. This conclusion of Pareto may have s i g n i f i c a n t e f f e c t on the attempts t o r e d i s t r i b u t e c i t y s i z e d i s t r butions away from or towards a Pareto-type d i s t r i b u t i o n or t o vary the 16 value of& ( t h e slope of the r e l a t i o n under log-normal conditions). Singer claimed t h a t : ... .... i n the d i s t r i b u t i o n of population among urban agglomer( f o r seven countries) t h e r e appears t o ations be a remarkable s t a t i s t i c a l r e g u l a r i t y , which besides being i n t e r e s t i n g i n i t s e l f and affording a complete analogy t o " P a r e t o ' s Law of Income Distribution, y i e l d s an exact quantat a t i v e measure f o r the r e l a t i v e r o l e s of t h e smaller and largertyyes humanagglomerations,i.e. a n i n d e x o f m e t r o ; polization. .... n'i Neither Singer, Allen, nor Champernowne have drawn any conclusioiis about the significance of the apparent r e l a t i o n s h i p between the Pareto income d i s t r i b u t i o n and c i t y s i z e d i s t r i b u t i o n s , an6 no doubt f o r very good reasons. l8 However it could be suggested t h a t Pareto-type d i s t r i b u t i o n s a r e "natural laws of d i s t r i b u t i o n " , conforming t o an optimum c i t y s i z e d i s t r i b u t i o n under open systems and where t h e r e a r e l a r g e and complex competitive forces operating on t h e c i t y s i z e d i s t r i b u t i o n . "Optimum" i s defined i n a very r e s t r i c t e d sense, t o r e f e r t o a d i s t r i b u t i o n towards which any d i s t r i 3 u t i o n tends under c e r t a i n complex competitive conditions ( i . e , t h e Pareto d i s t r i b u t i o n ) . This assumes t h a t s o c i a l , ec- onomic, p o l i t i c a l , and other forces a r e minimized when t h i s d i s t r i b u t i o n i s a t t a i n e d and it i s i n essence an equilibrium d i s t r i b u t i o n where forces a c t i n g t o maintain t h i s equilibrium d i s t r i b u t i o n dominate forces a c t i n g ' t o d i s t o r t t h i s d i s t r i b u t i o n away from equilibri~un. A t e n t a t i v e hypot h e s i s might be that: the more a c i t y s i z e d i s t r i b u t i o n conforms t o the Pareto d i s t r i b u t i o n , the more it represents an optimum d i s t r i b u t i o n under a l a r g e competitive economid system. . Thus a measure of non-optimality could be the deviations any one c i t y s i z e d i s t r i b u t i o n has, a t every level from t h e Pareto d i s t r i b u t i o n . These deviations would be very l a r g e i n the case of t h e primate d i s t r i b u t i o n , and the question therefore a r i s e s of i d e n t i f y i n g those forces which have caused t h i s deviation from t h e Pareto d i s t r i b u t i o n . 111. ZIPF AND TEE RANK-SIZE RULE Zipf 19 has pro5ably the best presentation of the empiri c a l findings on rank and s i z e of c i t i e s . The rank-size r u l e s t a t e s t h a t f o r a group of c i t i e s , usually those exceeding some size i n a p a r t i c u l a r country, the r e l a t i o n s h i p between s i z e and rank of c i t i e s i s of the form: where P,* = population of a c i t y of rank 3 q = = T' population of l a r g e s t o r first-ranking c i t y ccmstailt Zipf's rank-size r u l e i s a s p e c i a l case of the Pareto-type of d i s t r i bution with q = 1 (and where q conforms t i n logarithms: l o g r = l o g pt-q 1.06 + , SO o i n~ the Pareto d i s t r i b u t i o n ) . t h a t a p l o t t i n g of rank against s i z e should give a s t r a i g h t l i n e with a slope of -q. Zipf explains t h e f a c t t h a t the exponent q equals unity i n the rank-size r u l e , i n terms of the e q ~ l i t yof the forces of d i v e r s i f i c a t i o n and unification i n t h e won20 Diversification tends t o minimize the d i f f i c u l t y of rwring raw O v a m a t e r i a l s t o t h e places where they a r e t o be pr&essed. u n i f i c a t i o n tends t o minimize t h e d i f f i c u l t y of moving processed materials t o t h e ultimate consluning populace. Thus i f a l l persons were located a t the same point then m.Ximum u n i f i c a t i o n would be achieved. 'fiere both the forces of diver- s i f i c a t i o n and u n i f i c a t i o n are a t work, a d i s t r i b u t i o n of population i s Presumed t o occur t h a t i s a t optimum with reference t o both f o r c e s . Since the force of d i v e r s i f i c a t i o n makes f o r a l a r g e r (n) number of smaller P . communities, whereas the f o r c e of unification makes f o r a smaller number of P communities, then an "optimum" c i t y s i z e d i s t r i b u t i o n e x i s t s when the d i s t r i b u t i o n follows the rank-size rule and the opposing forces of divers i f i c a t i o n and unification are eqmlized. However : ... it i s c e r t a i n l y not clear what are the l o g i c a l l i n k s betwee:~the scheme proposed by Zipf t o explain rank-size regul a r i t y and observed rank-size regularity. 21 I s a r d , w r i t i n g i n 1956, a l s o has considerable scepticism about the ranks i z e rule: ... how much v a l i d i t y and universality should be a t t r i b u t e d t o t h i s rank-size r u l e i s , a t t i s stage, a matter of i n d i vidual opinion and judgement. 28 A number of other authors have a l s o questioned the v a l i d i t y of the rank- size rule. Stewart argues t h a t : ... The so-called rank-size r u l e i s an empirical finding not a l o g i c a l s t r u c t u r e . Nevertheless, it p a r t i a l v e r i f i c a t i o n suggests an underlying l o g i c a l b a s i s . $3 Furthermore stewart decided t h a t large heterogeneous areas f i t the model b e t t e r than small r e l a t i v e l y homogeneous areas, and t h a t t h e rank-size r u l e (1 breaks down i n many areas a t both extremes-&he l a r g e s t and smallest towns" and t h a t well-structured areas of urloan dominance tend t o have an S-shaped r a t h e r than a l i n e a r logarithmic d i s t r i b u t i o n of towns by s i z e . 24 It cannot be clenied, however, t h a t t o a limited extent t h e r e i s some b a s i s f o r t h e formulation of hypotheses and a d d i t i o n a l exploration on the nature of t h e r e l a t i o n s h i p between the rank-size r u l e and an optimlm c i t y size 6istribution. I n terms of the forces of unification and diver- s i f i c a t i o n it could be argued t h a t i n those developing countries i n which there is a predominance of small towns, there is also a predominance of the forces of diversification over those of unification. Iv. ClRI STALLEX AND THE SIZE CLASSES O F CITIES A w e l l known a l t e r n a t i v e i n t e r p r e t a t i o n t o t h a t of Zipf, both regarding t h e s i z e of c i t i e s and t h e processes cauing s i z e r e g u l a r i t i e s , i s t h a t of Walter C h r i s t a l l e r . 25 C h r i s t a l l e r a r e s i m i l a r i n many respects. , The schemes of Zipf and ~ 0 t hu t i l i z e notions of t h e do- main of c i t i e s (domain of goods) f o r t h e performance of various economic a c t i v i t i e s and t h e r u l e s of behavior leading t o the s p a t i a l s y s t c l of c e n t r a l p l a c e s and associated arrangements of c i t y s i z e s (diversifica- t i o n and u n i f i c a t i o n ) a r e q u i t e s i m i l a r . However f o r comparative.purposes C h r i s t a l l e r only present e d a formal theory of c i t y s i z e s and t h e i r d i s t r i b u t i o n f o r h i s k=3 n e t work of c i t i e s i n homogeneous space. 26 hierarchy of centres be taken a s ranks r ~ n t h e k=3 network, l e t . t h e = 1, 2, 3 .... and t h e pop- u l a t i o n of l a r g e s t c i t y (primate c i t y ) = K, second l a r g e s t r a n k a g c i t i e s K/3, e t c . = A rank-size d i s t r i b u t i o n i n t h e manner of Zipf i s formed if t h e exponent : thus where = 2 and i f q l o g P = l o g ( K/p ) K then l o g P = l o g ( 1 2 ) . and P = K/3 a s required by C h r i s t a l l e r ' s theory. 27 C h r i s t a l l e r , i n f a c t , t r e a t e d h i s formulation of t h e b a s i s of a h i e r a r c h i c a l system of c i t i e s a s an a n a l y t i c a l problem of determining a r a t i o n a l or "optimum" s p a t i a l o r i e n t a t i o n of c i t i e s . In Christaller's case we should be very cautious about i n t e r p r e t i n g h i s system of spacing and s i z e d i s t r i b u t i o n of c i t i e s as i n any sense optimal, 28 although it i s e s s e n t i a l l y a deductive theory from general assumptions, since it i s a r e l a t i o n s h i p between rank and s i z e of the c i t y ' s t r i b u t a r y areas and. not i t s population. 29 V. THE, CITY -SIZE ---- DISTRIBUTION AS A STOCHASTIC PROCESS The general shape of the observed c i t y - s i z e d i s t r i b u t i o n has l e d many recent students t o consider t h e d i s t r i b u t i o n a s generated by , - stocahstic growth processes. An e a r l y attempt t o formulate such an ap- prdach was by Chanpernowne, 30 with regards t o t h e Pareto income d i s t r bution, and by Stouffer i n r e l a t i o n t o migration p a t t e r n s , 3' who derived a Yule-type d i s t r i b u t i o r , f o r mobility and distance of migration. 32 Simon 33 has argued t h a t t h e d i s t r i b u t i o n of c i t y - s i z e s wag one of a family of d i s t r i b u t i o n s which have t h e following general c h a r a c t e r i s t i c s i n common: (a) They a r e J-shaped, o r a t l e a s t highly skewed, with very long t a i l s which can be approximated c l o s e l y by a function of t h e t h e form: f ( i ) = (a/ik)bi, where a , b, and k a r e constants, and t h e convergence f a c t o r b i s so c l o s e t o l t h a t it o f t e n may be dis?..egarded. Thus, f o r example, t h e ) number of . c i t i e s t h a t have a population i i s approximately a/ik. (b) The exponent, k i s of t h e form 1<k C 2 . (c) The function describes t h e d i s t r i b u t i o n , not merely i n t h e t a i l , b u t a l s o f o r small value of i. These t h r e e p r o p e r t i e s j u s t i d e n t i f i e d , define t h e c l a s s of functions which Simon terms t h e Yule D i s t r i b u t i o n . S t a t e d i n t h e s e terms, t h e d i s t r i b u t i o n f o r c i t y s i z e s i s evolved under roughly t h e following notions. k d i s t r i b n t e d i n c i t i e s , with a c i t y considered t o be an aggregate of population l a r g e r than some t h r e s h c l d s i z e . (k Consider a t o t a l population The p r o b a b i l i t y t h a t t h e + 1 ) s t person being found i n c i t i e s of s i z e i i s assumed t o be pro- portional t o i f ( i , k ) . It i s a l s o assumed t h e r e i s a constant p r o b a b i l i t y 3 t h a t t h e ( k = l ) s t person w i l l be i n c i - t i e s not previously of threshold ,size when the t o t a l p q u l a t i o n was k. Thus a model f o r expected- c l t y s i z e d i s t r i b u t i o n s can be calculated a s follows from a s e t of equetions derived from Simon' s o r i g i n a l model.: 34 Let ( i ) -3( = Wlk 1 (ii) f(l)=n~/~-o( where K i s the t o t a l urban population i n the n~ c i t i e s of greater than threshold s i z e . where n i s the number of c i t i e s equal t o o r greater than threshold s i z e of population k. and f ( i ) = number of c i t i e s of population i. From equations ( i ) and ( i i ) and the successive' application of equation ( i i i ) , the expected d i s t r i b u t i o n of c i t y s i z e s can be constructed. Since the s i t u a t i o n w i l l scarcely, i f ever be found i n which d76 (where i s an extremely small nmber) , we may w r i t e t h i s system i n the more simplified form: then from ( i i ) * and by successive application of (ij.i)*, the expected d i s t r i b u t i o n of c i t y s i z e s may be constructed. The d i s t r i b u t i o n of f ( i ) , t h e number of c i t i e s of s i z e i, may be r e a d i l y converted i n t o the rank-size d i s t r i b u t i o n , whefi'e b i s the number of c i t i e s of s i z e equal t o o r g r e a t e r than s i z e i, by the use of t h e following tr3.nsPrmation: wherek i s the number of centres of population equal t o o r g r e a t e r than s i z e i, nK i s a s before. and f ( i j ) i s the t o t a l number of centres of population l e s s than i. . Another s t o c h a s t i c theory of c i t y s i z e d i s t r i b u t i o n i s t h a t of Thomas. 35 Thomas notes t h a t J e f f e r s o n ' s formulation of the q u a l i t a t i v e "law of the primate city" evidences recognition t h a t the unequal population s i z e s of c i t i e s presents problems "worthy of investigation" . 36 Jefferson' s notion t h a t a country' s leading c i t y i s always d i s - proportionately l a r g e and exceptionally expressive of n a t i o n a l capacity and f e e l i n g implies t h a t functional changes i n the nature of the c i t y accompanies changes i n population s i z e . However because of the q u a l i t a - t i v e nature of the "~aw", it i s not possible t o a s c e r t a i n what i s meant by "disproportionately large". This term, when attached t o a p a r t i c u l a r ob- servation, i n d i c a t e s t h a t the magnitude of the observation exceeds some expected value, but no precise expected value i s provided by Jefferson. I n Chris'caller's scheme of c i t i e s the l a r g e s t c i t y i n an a r e a was not "disproportionately large", but merely "as l a r g e as it should be." Thomas' purpose was therefore t o develop a model of c i t y d i s t r i b u t i o n s which was consistent with the observed f a c t s and could poss i b l y provide an "expected" c i t y s i z e d i s t r i b u t i o n , and t h a t t h i s "ideal" . c i t y s i z e d i s t r i b u t i o n was based on the log-normal d i s t r i b u t i o n o r v a r i a - t i o n s of it. This log-normal d i s t r i b u t i o n ( o r "steady state'' d i s t r i b u t i o n ) w i l l occur under c e r t a i n basic assumptions. These a r e fourfold: MODEL 1 (i) No c i t y has a l o c a t i o n a l advantage i n r e l a t i o n t o physical and c u l t u r a l c h a r a c t e r i s t i c s of the area, thus the population of c i t i e s d i f f e r s only by chance. (ii) X l a r g e number of independent forces determine t h e populztion s i z e o r changes i n the population s i z e of cities. The change i n population s i z e of a c i t y i n r e l a t i o n t o i t s i n i t i a l s i z e i s very small during any one period. (iii) Growth of c i t y s i z e i s proportional t o c i t y s i z e . 37 (iv) The development of a log-normal frequency d i s t r i b u t i o n of c i t y s i z e o c c u ~ sa s f o l l o ~ ~ s : let X 0 = population s i z e a t i n i t i a l time period ( t o ) X1 = population s i z e a t end of time period ( t l ) hence growth of c i t y from tl b u t r e l a t i v e growth G = X1 - Xo -t .O ' = - Xo .. . X1 Xo 1x0 thus X1 and X1 = GIXo s Xo = x 0 ( G 1 = GIXo + 1) n.b. Magnitude of G1 i s independent of Xo ( ~ s s u m p t i o n( i v ) ) Therefore over n . time i n t e r v a l s However . /X = logex 'Xn=logeN - logeXo Xo Therefore s u b s t i t u t i n g i n (1.5) gives M G = l o g X - logeXo e n K4 2 o r l o g e s = logeXo Thus i f G1, + G1 + G2 + ... .Gn , + Gn 8 are stochasticallyindependent,then-G K=C normal d i s t r i b u t i o n a s n->G2....Gn Hence, logeXn i s normally dlst r i b u t e d , and i s log-normally d i s t r i b u t e d . Xn leads t o a MODEL 2 The development of a log-normal frequency d i s t r i b u t i o n of c i t y size. (i) Physical and c u l t u r a l v a r i a b l e s which a f f e c t c i t y s i z e a r e unevenly d i s t r i b u t e d over t h e area. Thus c e r t a i n c i t i e s w i l l have more favourable l o c a t i o n s than o t h e r s . The e f f e c t of differences i n q u a l i t y of l o c a t i o n i s t o d i f f e r e n t i a t e c i t y populattion s i z e s , t h a t i s , even a t t h e o u t s e t , population s i z e cannot be t r e a t e d a s a normally d i s t r i b u t e d "error" term. ( i i ) t o ( i v ) a s before. Assuming t h a t t h e i n i t i a l s i z e d i s t r i b u t i o n w i l l be log-normal i n form; what s o r t of d i s t r i b u t i o n w i l l a r i s e i f a new s e t of f o r c e s ( o r o l d ones strengthened) a c t on t h e d i s t r i b u t i o n ? l e t Xo = i n i t i a l population s i z e a t to, X1 = population s i z e a t tl Yo = transformation of X 0 i n t o n a t u r a l logarithms, t h e r e f o r e Yo = logeXo n.b. Yo i s normally d i s t r i b u t e d (See Model 1 ) Therefore absolute change i n Yo i n period = Y1 - Yo r e l a t i v e change i n Yo i n period = B 1 = Y 1 Theref ore f o r tn we have n z B = & ~k - Yk &I J=I Yk - - YO/yO -1 AS before n.b. Since logeY, i s normally d i s t r i b u t e d , and Y, = logeXn t h e l o g a r ithms of t h e l o g a r i t h m of Xn a r e normally distributed. Therefore transforining t o anti-logarithms, we may say t h a t t h e frequency d i s t r i b u t i o n of c i t y population s i z e assumes very skew log-lognormal form. The Law of Proportionate Effect i s a l s o a l t e r e d : a Since El = Y1 - YO/yo Tnen Y 1 = BIYo i.e . log,xl = + Yo log,^, (2.6) -i logexo which gives X1 = XoBXo = X,(B (2.7) + 1) (2.8) Thus w i t h i n a s t o c h a s t i c framework, we can s t a t e t h a t t h e log-lognormal d i s t r i b u t i o n occurs when growth a t any s t e p of t h e process i s a random power of t h e ' p r e v i o u s population s i z e . Thomas t e s t e d the s i z e d i s t r i b u t i o n of eighty-nine c i t i e s f o r Iowa in 1930 and f o m d t h a t t h e d i s t r i b u t i o n approximated. t h e loglognormal d i s t r i b u t i o n , r a t h e r than t h e log-normal. 38 Kalecki, has shown however, t h a t over a long time t h e skewedness. of successive frequency d i s t r i b u t i o n s i n c r e a s e s . 39 porate t h i s tendency over a . Thomas has developed a separate model t o i n c o r 40 Madden, i n a study of t h e growth of U.S. c i t i e s 100 year period from 1790 t o 1950 has demonstrated the s t a b i l i t y of t h e rank-size (hg-normal) d i s t r i b u t i o n over time, despite t h e f a c t t h a t i n d i v i d u a l c i t i e s moved a3out over f a i r l y wide ranges within t h e rarkage. The changes i n rank by s i z e of t h e d i f f e r e n t l a r g e c i t i e s of t h e n a t i o n presumably r e f l e c t t h e changing r o l e s played by c i t i e s i n t h e population system; t h a t i s , they r e f l e c t t h e charging shares of t h e t o t a l urban ec- onomic a c t i v i t y obtained by these c i t i e s a t various decades. Similarly, it was shown t h a t t h e percentage growth of c i t i e s ( i n terms of a mean growth f o r d i f f e r e n t s i z e groups), i s unrelated t o t h e p o s i t i o n of t h e c i t y i n t h e general d i s t r i b u t i o n , confirming a previous formulation by Vining, 41 which i s very s i m i l a r t o t h a t derived by Thomas. The empirical evidence from both developed and developing c o r n t r i e s seems t o suggest t h a t t h e log-nmmal d i s t r i b u t i o n o r v a r i a t i o n s of it f o r c i t y s i z e s i s f a i r l y common. It has been demonstrated t h a t t h e log-ncrmal d i s t r i b u t i o n and the log-lognormal d i s t r i b u t i o n ( classes of Yule d i s t r i b u t i o n s ) =ise, growth processes over time. under c e r t a i n conditions, out of s t o c h a s t i c These d i s t r i b u t i o n s are "steady s t a t e " o r " s t a t i s t i c a l equilibrium", or "natural law" d i s t r i b u t i o n s . The log- normal d i s t r i b u t i o n appears t o a r i s e out of s t o c h a s t i c growth processes i n an open system and where the p r o b a b i l i t y of growth of an individual c i t y i s simply proportional t o the c i t y s i z e . The log-lognormal d i s t r i - bution a r i s e s out of s t o c h a s t i c growth processes i n a closed system, and growth i s a random power of s i z e of c i t y . 42 -25IV. CITY SIZE DISTRIBUTIONS AND POLICY CONSIDEMTIONS The questions now a r i s e , o f which d i s t r i b u t i o n b e s t describes t h e c i t y - s i z e d i s t r i b u t i o n i n developing countries, and what a r e t h e causes behind t h e v a r i a t i o n s between t h e c i t y s i z e d i s t r i b u t i o n ? What, f o r example would b e . t h e e f f e c t on national economic growth of attempts t o change a c i t y s i z e d i s t r i b u t i o n from a log-normal t o a non log-normal distribution? This has considerable relevance f o r c e n t r a l i z a t i o n o r de- c e n t r a l i z a t i o n policies- i s a d e c e n t r a l i z a t i o n p o l i c y under c e r t a i n con- d i t i o n s going t o l e a d t o considerable changes i n t h e whole of t h e dist r i b u t i o n such t h a t it : i s no longer i n a s t a t e of s t a t i s t i c a l equilibrium o r i n a steady s t a t e ? Assuming t h a t t h e log-normal d i s t r i b u t i o n i s an optimum d i s t r i b u t i o n i n a s i t u a t i o n where t h e r e a r e a largenunber of random and competitive f o r c e s operating i n t h e socio-economic and p o l i t i c a l systems, i s t h e r e l i k e l y t o be a most e f f i c i e n t a l l o c a t i o n of c i t y s i z e s w h e n t h e d i s t r i b u t i o n conforms t o t h e log-normal d i s t r i b u t i o n ? If t h e answer i s i n t h e a f f i r m a t i v e , can one a l s o assume t h a t econoraic growth (and growth i n t h e average s i z e o f c i t i e s ) i s ~naximizedwith t h i s type of d i s t r i b u t i o n ? P o l i c i e s f o r decentralizing economic a c t i v i t i e s have been c r i t i c i z e d on t h e b a s i s t h a t economic growth i s maximized when it i s conc e n t r a t e d i n c e r t a i n faxourable l a r g e urban areas, i . e . t h e growth pole theory. 43 The argument i s t h a t by v e r t i c a l and h o r i z o n t a l linkage e f f e c t s and a spi.llover of growth from one region o r c i t y t o another, t h e whole system w i l l grow a t a f a s t e r r a t e than under any o t h e r conditions. Critics of d e c e n t r a l i z a t i o n p o l i c i e s have c o n s i s t e n t l y argued t h i s point f o r many years. Furthermore i n terms of t h e attempts t o impose maximum l i m i t s t o the s i z e of t h e l a r g e s t c i t y , it i s i n t e r e s t i n g t o conjecture about t h e possible e f f e c t s such a policy would have under d i f f e r e n t i n i t i a l cond i t i o n s , on t h e whole d i s t r i b u t i o n of c i t i e s . Randomness i s postulated a s a convenient technique f o r i n v e s t i gating the o v e r a l l properties of the settlement f i e l d . 44 Such a form- ulation i s n e u t r a l as t o r a t i o n a l i t y whether s o c i a l l y or econonically oriented: every decision may be optimal from a p a r t i c u l a r point of view and y e t t h e r e s u l t i n g actions as a whole may appear a s random. Lack of information, s o c i a l t i e s and so on w i l l change an economizing optimizing problem but not the randomness formulation. Since it i s not possible t o i d e n t i f y and measure a l l the forces t h a t c o n t r o l t h e c i t y s i z e d i s t r i b u t i o n , t h e observation t h a t c i t y s i z e d i s t r i b u t i o n s tend towards the log-normal under competitive forces may provide a clue to the formulation of policy decisions under c z r t a i n c i r cumstances. A town planner, f o r example, t r i e s t o reconcile a whole s e r i e s of opposing f o r c e s , t o achieve some form of s o c i a l optimum c i t y s i z e and d i s t r i b u t i o n of c i t i e s , and often finds it impossible t o a r r i v e a t some unique solution. Yet empirical evidence shows t h a t under c e r t a i n con- d i t i o n s , t h a t of a large competitive system, c i t y s i z e d i s t r i b u t i o n s tend towards the log-normal o r log-lognormal. I t could be argued therefore t h a t any d i s t r i b u t i o n t h a t does not conform t o the log-normal d i s t r i b u t i o n i s non-optimal a t t h a t point i n time. Thus primate c i t y d i s t r i b u t i o n s , wi~ich have a r i s e n out of peculiar h i s t o r i c a l , geographical, sociological, poli t i c a l , o r economic forces are non-optimal. This hypothesis would suggest t h a t a policy of e i t h e r heavily investing i n intermediate s i z e citie-s o r of reducing the primacy of the l a r g e s t c i t y w i l l encourage a move toward an optimum. ( See Diagram 2) A policy of r e s t r i c t i n g the absolute growth of t h e l a r g e s t c i t y i n a country, could have some undesirable a f f e c t s on the o v e r a l l r a t e of growth of a l l other c i t i e s , e s p e c i a l l y if the e x i s t i n g d i s t r i b u t i o n of c i t i e s i s the log-nornel. I n t h i s case, t h e r e would be a growth of intermediate s i z e c i t i e s and f u r t h e r deviation from the lognormal d i s t r i b u t i o n . (see Diagram 3) I n t e r e s t i n g analogies t o the problem of policy considerations with respect t o c i t y s i z e d i s t r i b u t i o n s have a r i s e n i n the case of t h e s i z e d i s t r i b u t i o n of firms. Simon and Bonini, 45 have noted t h a t t h e s i z e d i s t r i b u t i o n of firms (whether within a single industry or a whole country), i s almost always highly skewed, and t h a t i t s upper t a i l resembles the Pareto ( o r log-normal) d i s t r i b u t i o n . Attempts a t economic explanation of t h e observed f a c t s about concentration of industry have always assumed t h a t t h e b a s i c causal mechanism was the slope of the long-run average cost curve; but t h e r e was l i t t l e discussion of why t h i s mechanism should produce, even occasionally, the p a r t i c u l a r highly skewed d i s t r i b u t i o n s t h a t are observed. The s t a t i c c o s t curve analysis y i e l d s no explanation a s t o why t h e observed d i s t r i b u t i o n s approximate the Pareto d i s t r i b u t i o n , it only shows a c r i t i c a l minimum s i z e of f i r m i n an industry. Simon and Bonini argued t h a t p l a n t cost clnves a r e generally J-shaped, and below sone c r i t i c a l s i z e u n i t c o s t s r i s e rapidly,above the c r i t i c a l s i z e c o s t s vary only s l i g h t l y with s i z e of f i r m : We can Eay then, t h a t , t h e c h a r a c t e r i s t i c cost curve f o r the No.of Cities smallest cities - Heavy investment in inter- mediate size cities. f '.~estrictionin size of largest city DIAGRAM 2: POSSIBLE EFFECTS of a FZDISTRIBUTION POLICY. No.of Cities ; Growth of intermediate cities with [the restriction of size,oflargest Restriction of the la-rgest city. deal" LOG-NOML (RANKSIZE) DISTRIBUTION. Size of City (log scale) FOSSIBLE EFFECTS of RESTRICTING the SIZE of the L4XGEST CITY. f i r m shows v i r t u a l l y constant returns t o s c a l e f o r s i z e s above some c r i t i c a l minimum. Under these circumstances the s t a t i c a n a l y s i s may p r e d i c t the minimum s i z e of firm i n an i@ustry b a t it w i l l not predict the s i z e d i s t r i b u t i o n of firms. Simon and Bonini attempt t o explain the s i z e d i s t r i b u t i o n of firms on the b a s i s of a s t o c h a s t i c model. They postulate (from an assumption) t h a t t h e d i s t r i b u t i o n of percentage changes i n s i z e of the firms (over a year) in. a given c l a s s s i z e i s the same f o r a l l c l a s s s i z e s . 47 - THE MODEL Assume there i s a minimum s i z e , Sm, of f i r m i n an industry. t h i s minimum s i z e , u n i t costs a r e constant. Above Individual firms i n the industry w i l l grow ( o r shrink) a t varying r a t e s depending on such f a c t o r s a s (a) ment, (d) profits, (b) dividends policy, (c) new invest- mergers. These f a c t o r s i n turn, may depend upon the e f f i c i e n c y of the 'individual firm, exclusive access t o p . w t i c u l a r f a c t o r s of production, consumer brand preference, the growth and decline of a p a r t i c u l a r industry, product i n .which it specializes, and numerous other conditions. 4! me operation of a l l these forces w i l l generate a probability d i s - t r i b u t i o n f o r the changes i n s i z e of firms of a given s i z e . Thus the f i r s t b a s i c assumption ( t h e Law of Proportionate ~ f f e c t )i s t h a t t h i s p r o b a b i l i t y d i s t r i b u t i o n i s the same f o r a l l s i z e c l a s s of firms t h a t a r e w e l l above 9 , . The second basic assumption d i s t r i b u t i o n i s t h a t new firms a r e being "born" i n the smallest s i z e c l a s s a t a r e l a t i v e l y constant r a t e . It has been shown t h a t under these assumptions the Yule Distribution + w i l l be t h e steady-state d i s t r i b u t i o n of t h e process. Then t h e Let f ( s ) d s be the p r o b a b i l i t y density of firms by s i z e s . Yule D i s t r i b u t i o n i s given by f ( s ) Where ~ ( s p, = K B ( S ,+ ~ 1). + 1) i s a Beta function of K i s a normalizing constant, p i s a parameter. It i s easy t o show t h a t a s S--tW, f (s) Pareto D i s t r i b u t i o n . s Ms -(P and ( p + 1) + 1). , which Thus i n considering any observed d i s t r i b u t i o n of f i r m i s the s i z e s above t h e c r i t i c a l minimum s i z e , ahy s u b s t a n t i a l deviation of t h e r e s u l t s from those p r e d i c t e d from t h e s t o c h a s t i c model i s a r e f l e c t i o n of some depart u r e fromthe Law of &oportionate Effect o r from one of t h e assumptions o f t h e model. Having observed such a departure, we can then t r y . t o provide f o r it some reasonable economic i n t e r p r e t a t i o n . Such a deviation may be a .measure of concentration, a s Aitchison and Brown argue. 5O The p a r m e t e r ( p ) can a l s o be used t o account f o r t h e d i s t r i b u t i o n of f i r m s i z e s , hence in t h i s p a r t i c u l a r model, t h e concentration i n an industry i s not i n dependently determined, but i s a function of t h e r a t e of new entry. (where p = 1 t h e r a t e of e n t r y cf new firms i n t o t h e system = 0 . ) 51 If f i r m s i z e s a r e determined by a s t o c h a s t i c process, then t h e appropriate way t o t h i n k about public policy i n t h i s area i s t o consider t h e means by which t h e s t o c h a s t i c process can be a l t e r e d , and t h e consequences of employing these means. As a very simple example, i f t h e r a t e of e n t r y i n t o t h e industry can be increased, t h i s w i l l automatically reduce t h e l e v e l of c o n c e n t r ~ t i o n , a s measured by the usual indices. Similarly, i f , through t a x p o l i c i e s o r o t h e r means, a s i t u a t i o n of sharply increasing c o s t s i s created i n an industry, t h i s s i t u a t i o n should cause a departure Trom the Yule Distribution, i n the d i r e c t i o n of lower concentration. Furthermore the same equilibrium d i s t r i b u t i o n may be produced with various degrees of mixing, i.e. reordering of t h e rank of firms in an industry, according t o the d i c t a t e s of desirable public policy goals ( i . e . mobility of firms versus concentration of firms) . Simon and Bonini a l s o suggest t h a t when the environment i s changizg a t a r a t e t h z t i s large compared w i t h the adaptive speeds of the organisms : . -- we can never expect t o observe the system i n the neighbourhood of equilibrium, and we must invoke some s u b s t i t u t e f o r the s t a t i c equilibrium if we wish t o p r e d i c t behaviour. 52 ; ; The problems of a r r i v i n g a t an optimum c i t y s i z e d i s t r i b u t i o n may be considered ?rum the same point .of view as t h a t adopted by Simon and Bonini. Much of the e x i s t i n g l i t e r a t u r e on c i t i e s , only considers the optimum s i z e of c i t i e s , and t h e r e i s l i t t l e reference t o the optimum s i z e d i s t r i b u t i o n of c i t i e s . I n considering, f o r example, the economic case f o r and a g a k s t a p o l i c y of encouraging the growth of l a r g e or small centres, o r t o see whether t h e r e i s any economic "virtue" i n a policy of decentralization, the approach suggested by Simon and Bonini may be useful. A decentralization plan has been followed i n Australia, f o r example, since a t l e a s t World War 11. On purely economic grounds it appears on f i r s t s i g h t t h a t it i s an unjusti f i a b l e policy, i n terms of e f f i c i e n t resource allocation, but on broader socio-ecmomic grounds it ;may be the reverse. According t o Berry's study 53 A u s t r a l i a has a c i t y s i z e d i s t r i b u t i o n t h a t i s intermediate between t h e log- I - This i s confirmed by Neutze 54 who remarks on: normal and the primate. ... the absence of medium s i z e high concentration of population i n the s t a t e c a p i t a l s and a dearth of medium sized centres. The absence of medium sized regional centres may have been a major f a c t o r causing new growth i n recent years t o crowd i n t o the s t a t e c a p i t a l s of Australia. Thus the appropriate policy might be t o promote some of these centres and provide a wider choice f o r firms t h a t f i n d location i n small centres unprofitable. 55 The argument f o r a decentralization policy i s u s u a l . 1 ~s t a t e d i n terms of n e t s o c i a l c o s t s and b e n e f i t s of r e d i s t r i b u t i o n of industry, people, employment, investment, e t c . , taking i n t o account e x t e r n a l i t i e s a n a t h e r e l a t i o n of the policy t o o v e r a l l growth. Among the external e f f e c t s of p r i v a t e (and public) l o c a t i o n decisions a r e those of t r a f f i c ' congest i o n and public expenditure on road building, etc., i n r e l a t i o n t o c i t y s i z e . 56 The general conclusion i s t h a t the e x t e r n a l costs of t r a f f i c growth w i l l be greater i n l a r g e r a t h e r than i n small centres. The same analysis can be applied t o parking f a c i l i t i e s , f a r e s i n public transport, length of journey t o work, and cost of public services, e t c . , e x t e r n a l diseconomies of growth. i n terms of Account must a l s o be taken of economies of s c a l e i n public services, government administration, the differences i n cost of p r i v a t e goods and services i n terms of v a r i a t i o n of p r i c e s with c i t y size. Intervention i n the market a l l o c a t i o n mechanism w i t h respect t o c i t i e s i s only j u s t i f i e d i f the pecuniary and non-pecuniary e x t e r n a l econonies and diseconomies a r e so large t h a t they cannot be ignored and i f t h e government intervention produces a more s o c i a l l y optimum fiistribution, - 33 t which it may w e l l not do under conditions of imperfect f o r e s i g h t . 57 One possible e x t e r n a l e f f e c t of growth of c i t i e s stems from s c a l e economies o r diseconomies i n the provision of public services, If public services a r e more expensive i n large c i t i e s , growth brings ex- t e r n a l diseconomies. Conversely, if c o s t s f a l l with growth there a r e e x t e r n a l economies. If we can measure the e f f e c t of s i z e of centre on these costs we can show the d i r e c t i o n and the magnitude of the e x t e r n a l e f f e c t s and a l s o t h e way they a f f e c t the r e l a t i v e a t t r a c t i v e n e s s of l a r g e and small centres. If we p l o t cost against s i z e and get a U-shaped average cost curve then the e x t e r n a l e f f e c t s w i l l be causing unduly large c i t i e s . They w i l l be doing so as long a s c o s t s r i s e more r a p i d l y or f a l l more slowly a s ropulation grows. Tne major problems, e s p e c i a l l y in developing countries, a r e not only t h e l a c k of data, but a l s o d i f - ferences i n q u a l i t y of serviees which may a f f e c t costs. 58 K.S. oma ax, 59 in an e a r l y study of B r i t i s h towns, found t h a t costs were lowest, i n terms of expenditure per head in centres of from 50,000 t o 100,000 people, however no account was taken of q u a l i t y differences i n services. Other studies ( e s p e c i a l l y i n ,$he U. S. ) have found very l i t t l e r e l a t i o n s h i p be - tween population of municipality and costs of local. government service, with the exception of whter, sewage, and education. I sard, 61 60 f o r example, has discussed the emergence of the s p a t i a l p a t t e r n of c i t i e s of d i f f e r e n t s i z e s i n terms of economies and diseconomies of s c a l e a r i s i n g from a c t i v i t i e s p o s i t i v e l y associated w i t h s i z e of c i t y (agglomeration and deglomeration economies). out of: Urbanization economies a r i s e ... a higher l e v e l of use of the general apparata of an urban s t r u c t u r e (such a s transpcirtation f a , c i l i t i e s , gas and water maims, and t h e l i k e ) and from a f i n e r a r t i c u l a t i o n of economic a c t i v i t i e s . ( d a i l y , seasonally, and i n t e r -indus tr i a l l y ) . Urbanization diseconomies a r e engendered by r i s e s i n the cost of l i v i n g and money wages, in the costs of l o c a l materials produced under conditions of diminishing r e t u r n s , i n time-cost and other costs of transportation, and i n land value and rents. C i t i e s a l s o a t t r a c t o r r e p e l unLts of production i n accordance with t h e urbanization ( f o r the most p a r t , external) economies o r d i s economies relevant t o each u n i t of production. I n considering the optimum s p a t i a l d i s t r i b u t i o n and hierarchy of d i f f e r e n t c i t i e s within a given technological and resource environment, such urban economies and diseconomies a r e important. It i s tempting t o define an o v e r a l l index of economy o r function of economy by summing a s e r i e s of n e t economies f o r d i f f e r e n t c i t y s i z e s t o a r r i v e a t an optimal s i z e of c i t y . I s a r d r e j e c t s t h i s procedure on the grounds t h a t t h e r e a r e t o o many " l o g i c a l objections". 62 Also: ... standardization of c i t i e s i s subject t o serious c r i t i c i s m . There a r e no standard c i t i e s , each i s unique. There i s a l s o a problem of weighting the importance of individual n e t economies curves. Another objection, perhaps the most serious of a l l , stems from the neglect of inter-dependence among the s e t s of n e t economies curve s : The above considerations are s u f f i c i e n t i n themselves t o i n v a l i d a t e the use, even i n an approximate fashion, of a s i m p l e t o t a l curve .or index of economies and diseconomies i n the functioning of c i t i e s of various s i z e s . 63 It appears t h a t we are thrown back t o cansidering the approach advocated by Simon and Bonini ( f o r f i r m s i z e d i s t r i b u t i o n s ) for the c i t y s i z e distribution also. Since we have so many competitive s o c i a l , economic, p o l i t i c a l , and other forces operating on the c i t y s i z e d i s t r i b u t i o n and it i s d i f f i c u l t t o i s o l a t e what may be t h e c r i t i c a l f a c t o r s determining t h e c i t y s i z e s and t h e i r d i s t r i b u t i o n , it would be more sound t o analyze t h e problem of optimum c i t y s i z e d i s t r i b u t i o n within the context of the t o t a l n a t i o n a l environment. - I n order t o f a c i l i t a t e our understanding of the integrated nature of the whole c i t y s i z e d i s t r i b u t i o n it; would be -- convenient and illuminating t o consicler the d i s t r i b u t i o n as a subsystem - i n a l a r g e r system of the functioning of society, I . - CIW SIZE DISTRIBUTIONS AND GENERAL SYSTEMS THEORY The s t a b i l i t y of the rank-size formulation over time tween nations 65 has been explained by various authors & steady s t a t e s t o c h a s t i c growth processes. 64 and be- i n terms of The tendency f o r l i v i n g systems t o maintain steady s t a t e s of many v a r i a b l e s which keep a l l subsystems i n order of balance both with one another and with t h e i r environment i s t h e essence of general systems theo~.y, These steady-states a r e described i n terms of entropy, i n accordance with the second Law of Thermodynamics, i n which maximum entropy i s a s t a t e of randomly d i s t r i b u t e d energy and e s s e n t i a l l y a normal o r average s t a t e of equilibrium. That t h e rank-size d i s t r i b u t i o n i s a random s t a t e i s borne out by Simon and as such it i s a proper subject o f systems theory. Thus c i t y s i z e d i s t r i b u t i o n s may be treate.d i n terms of average conditions of maximum entropy and i n the more general context of the development of systems theory. 67 A broad review of the unifying nature of general systems theory i n r e l a t i o n t o what has been discussed so f a r i s i n order a t t h i s juncture. A system i s a s e t of 'objects ( f o r example, c e n t r a l places), a t t r i b u t e s of the objects (population, establishinents , business types, t r a f f i c generated), i n t e r - r e l a t i o n s h i p s among the objects (mid-point locations f o r lower l e v e l centres, uniform spacing a t any given l e v e l ) , and among the a t t r i b u t e s ( t h e c e n t r a l place hierarchy). Systems may be closed, i . e . e n t i r e l y self-contained,or open, i n the sense t h a t they exchange energy (materials, messages, and ideas) with a surrounding environment. available t o do work. Closed systems have a given energy supply As work i s performed the energy i s d i s s i p a t e d and w i l l eventually become randomly distr-ibuted t h r o u & o ~ t the system. Using the terminology of the second Law of Thermodynamics, the systein w i l l then have reached a condition of maximum e n t r ~ p y . I n terms of c e n t r a l place theory, a c e n t r a l place system, if it were closed and had run down t o a s t a t e of maximum entropy then populztion and other a t t r i b u t e s of centres would be completely u n r e l a t e i t o l e v e l of centres i n the hierarchy. In f a c t any t r a c e of hierarchy would vanish. With r e l a t i v e constancy i n energy inputs and approximate balance . of inputs and outputs, open systems s e t t l e i n t o an organized equilibrium between the tendency t o move toward maximum entropy and t h e need f o r organization t o pcrform work. steady-state. Such an organized equilibrium is c a l l e d a A central-place system i s open. The central place h i e r - archy i s a form of organization t h a t performs the work involved as e f f i c i e n t l y a s possible, and the rank s i z e r e g u l a r i t y i s a manifestation of a steady-state equilibrium. A steady-state balances (1) organization i n t o a hierarchy to'perforrn the work e f f i c i e n t l y , randomization due t o chance l o c a l differences. the need f o r and (2) Any decrease i n energy i n - puts increases the entropy i n an open system, and causes adjustments changing the form of the steady-state. By the same token, increasing energy inputs cause form adjustments leading t o 3 . t h e . r organization ( o r negative entropy). Open syst&ms a l s o contain feedback mech~nismst h a t a f f e c t growth even under conditions of constant energy inputs. positive feedback would tend t o decrease the randomizing e f f e c t s of l o c a l v a r i a b i l i t y , ant! negative feedback t o increase them, thus respectively increasing e i t h e r organization o r entropy. One conclusion of t h e general systems t h e o r i s t s is worthy of- ncLe: The steady s t a t e i n an open system i s one t h a t obeys p r i n c i p l e s of equifinality. Whatever t h e i n i t i a l s i z e of t h e c e n t r a l places, t h e sane c i t y s t e a d y - s t a t e w i l l be achieved provided t h e energy flows a r e t h e same. The steady-state r e s u l t s s o l e l y from energy flows, independ-ent of t h e i n i t i a l s i z e conditions. Thus a rank-size r e l a t i o n s h i p w i l l r e s u l t s o l e l y from t h e b a l a n c e , o f l o c a l v a r i a b i l i t y and t h e o r g a n i z a t i o n a l needs f o r a hierarchy under a given s e t of demand and supply c m d i t i o n s . This i s a l s o a char- a c t e r i s t i c of t h e competitive model used t~ d e r i v e a central-place system. Barry has attempted t o i n t e g r a t e many of t h e 'elements of systems of cent r a l places i n t o t h e general systems approach, t h u s incorporating c e n t r a l - 68 Berry place theory. s t a t e s t h a t c i t i e s and s e t s of c i t i e s a r e systems s u s c e p t i b l e t o tile same kinds of g e n e r a l i z a t i o n s , constructs, and models, a s i n general systems theory since c i t y systems ,incorporate t h e two complementary ideas of entropy and information. b t r o p y i s achieved i n t h e s t e a d y - s t a t e of a sfuochastic process and i s , a s has been s t a t e d bef o r e , a t i t s maximum , i f , t h i s proce'ss i s uncofistrained ( t h e rank-size r u l e ) . 69 Consider t h e case where t h e aim i s t o divide N people among two s e t t l e m e n t s , each hdving an equal c h n c e of a t t r a c t i n g a given population. Let t h e number of settlements 3aving a population of i persons N be Zi, and 5 zi = 1. The numbex of. r a y s i n which people can be d i s - is0 t r i b u t e d mong t h e set,tlemeni;s, ncgiec-king t h e s p a t i a l aspect and cons i d e r i n g only t h e frequericy d i s t r i b u t i o n i s g = '!/N TT Zit. (05 i5N) When t h e system i s l a r g e i t s entropy i s : Where H = entropy. -i/n H i s maximized when Zi = (Z/N) N Where n = /Z, t h e mean population per settlement. This exponential d i s t r i b u t i o n can be w r i t t e n a s a cumulative d i s t r i b u t i o n function: Where T = s i z e of l a r g e s t c i t y . Under t h e s e circumstances, entropy i s maximized when Hmax = log(^^), i.e. t h e most probable s t a t e of t h e system i s t h a t which gives mcaximum entropy, o r when the sum of logarithms i s a maximum. This corresponds -Lo a s i t - uation i n which, given t h e s i z e of t h e l a r g e s t c i t y , t h e p r o b a b i l i t y t h a t the (u + 1 ) s t c i t y has a population P(U + 1 ) i s equal t o q. Where P = P(" with ~ ( u )= t h e p o p h a t i o n of t h e l a r g e s t c i t y . + p( u) The r a t i o I n t h i s sense q = i s a constant. log(^^) becomes s i m i l a r t o t h e r a n k - s i z e r u l e : It a l s o follows t h a t a system of c i t i e s obeying t h e rank-size r u l e i s i n a s t a t e of equilibrium i n which entropy has been maximized. t h i s reason t h a t Berry and Garrison 70 and Curry 71 It i s f o r argue t h a t systems which deviate from the rank-size r u l e a r e more worthy of a t t e n t i o n than a r e s y s t e m ~ M c hfollow. It i s i n t h i s sense t h a t t h e prima.te c i t y d i s - t r i b u t i o n h&s such i n t e r e s t i n r e l a t i o n t o developing countries. Are they a l s o a d i s t r i b u t i o n i n disequilibrium i n terms of t h e entropy concept? Maruyama s t a t e s t h a t e q u i l i b r i a t i n g theory ( c y b e r n e t i c s ) may have a c o n t r a d i c t i o n i n t h e form of a d i s e q u i l i b r i a t i n g system. Many i n s t a n c e s can be c i t e d i n which feedback does not l e a d t o s e l f - c o r r e c t i o n s towards some pre-set e q u i l i b r i u n (morphostasis), 729 73 state distribution. i n t h e form of t h e steady- Rather, progressively g r e a t e r c o n t r a s t s appear a s f o r example, between Myrdal's Rich Lands and Poor Lands, T4 o r with pro- g r e s s i v e l y g r e a t e r c e n t r a l i z a t i o n of functions i n fewer l a r g e c i t i e s , o r when "the growth of a c i t y increases t h e i n t e r n a l structuredness of t h e city itself. 11 75 Maruyama's t h e s i s i s r e l e v a n t t o t h e problem of t h e f a n t a s t i c growth of primate c i t i e s i n many underdeveloped countries. Could t h e s e primate c i t i e s be examples of a deviation amplifying mutual c a u s a l process, which w i l l take c e r t a i n underdeveloped c o u n t r i e s , further away from t h e h y p o t h e t i c a l optimum equilibrium c i t y s i z e d i s t r i b u t i o n . That this i s a s e r i o u s p o s s i b i l i t y should not be discounted. I n an economically underdeveloped s b c i e t y , on t h e o t h e r hand under the laissez-faire policy and free play of market f o r c e s , t h e few p r i v i l e g e d people accumulate more power and we while t h e l i v i n g standards of t h e poor tends t o f a l l . ?kth Berry argues t h a t t h i s deviation (and t h e r e f o r e s t r u c t u r e ) amplifying t r e n d i n a system i s a tendency towards maxiram information and reordering, and away from maxiinum entropy. Thus t h e two f o r c e s a r e essen- t i a l l y i n opposition. 77 A gl.ance a t t h e d a t e f o r t h e U.S. shows it t o be more o r d e ~ ~ 2 than I n d i a , a n d l e s s than A u s t r a l i a , f o r example. 78 The evidence presented by Berry on c i t y s i z e d i s t r i b u t i o n s and economic development, suggests t h a t although c i t y s i z e d i s t r i b u t i o n s a r e essent i a l l y uncorrelated t o l e v e l s of development, they a r e c o r r e l a t e d with o t h e r f a c t o r s of a country's development, such a s s i z e of t h e country, age of urbanization, e t c . The log-normal d i s t r i b u t i o n i s hypothesized a s r e p r e s e n t i n g a s t e a d y - s t a t e condition of maximum entropy, whereas a primate d i s t r i b u t i o n may i n d i c a t e a simpler, p a t t e r n e d s t r u c t u r e . Pro- gression from the primate t o the log-normal s t a g e i s reached when t h e urban s o c i e t y i s o l d and complex and has been influenced by ,large numbers of f o r c e s i n many ways such t h a t t h e p a t t e r n i n g e f f e c t s of any of t h e s e forces are l o s t . Evidence t o support t h i s h y p t h e s i s was found i n t h e f a c t t h a t t h e advanced c o u n t r i e s with primate dLstributions were very small, which l i m i t e d possible complexitie,t e n t e r i n g int,o t h e urban scene, and t h e l e s s e r developed c o u n t r i e s with 1-og-cormal d i s t r i b u t i o n s were g e n e r a l l y very l a r g e and with long h i s t o r i e s of urbanization which i n creased t h e p o s ' s i b i l i t y of t h e urban p a t t e r n being a f f e c t e d by many f o r c e s . However it i s d i f f i c u l t t o be c e r t a i n t h a t those countries which do d i s p l a y a log-normal d i s t r i b u t i o n have i n f a c t an equilibrium c i t y s i z e d i s t r i b u t i o n i n t h e sense t h a t t h e r e i s no pressure t o move away from t h i s equilibrium d i s t r i b u % i o n . I n order t o exaliine whether t h e r e i s a sodioeconomic end p o l i t i c a l optimum i n a country with a log-normal d i s t r i b u t i o n , t h e c i t y s i z e d i s t r i b n t . i o n of I n d i a w i l l be examined. VIII. INDIAN CITY SIZE DISTRIBUTION The r a t e of iwban population growth i n India i n the l a s t Tew decades has been phenomenal. From 1941 t o 1951 the growth was from 13.5% t o 17.3% of t h e t o t a l population, representing an urban growth of 34.8%. The.growth of urban places i n and by i t s e l f would be of l e s s concern i f it d i d not produce a t t h e sane time a number of s o c i a l a r e new and demand constructive solutiibns. which Unemployment i n Indian c i t i e s i s high, e s p e c i a l l y among educated persons, and t h i s c r e a t e s s o c i a l and p o l i t i c a l problems, The growth of c i t i e s i s due i n large p a r t t o r u r a l - urban migration, the conditions and causes of which w e s t i l l l i t t l e understood. Moreover, housing, water supply, and s z n i t a r y services a r e s o r e l y lacking i n . Indian c i t i e s , and the r a p i d growLh of population c r e a t e s increasing pressures t o supply even minimum f a c i l i t i e s of t h i s kind. Viis makes necessary some action i n the d i r e c t i o n of urban planning i n order t o b e t t e r balance short run and long run needs. Much of the present growth of c i t i e s takes place by the building of shanty towns, which a r e being b u i l t on any piece of land t h a t happens t o be available, I n d i m c i t i e s , and e s p e c i a l l y the smaller towns, s u f f e r from a plethora of slums. Thus it appears t h a t even though it has a log-normal d i s t r i - bution, Indian c i t i e s are not without t h e i r problems. I n a s much a s these urban centres ( e s p e c i a l l y those over 100,000) form a system, and i n t h a t capacity, a f f e c t t h e urban and economic s t r u c t u r e of India, it i s of i n t e r e s t t o analyze the properties of the urban centres comprising t h e system. Along what dimensions of v a r i a t i o n can Indian c i t i e s be arranged? &t a r e the major s i m i l a r i t i e s and differences t h a t chara c t e r i z e these r e l a t i v e l y large, urban agglomerations? Harris and Ullman, 79 summarized t h e c l a s s i c a l p r i n c i p l e s of urbanization by recognizing three d i f f e r e n t types of c i t i e s : 1. C i t i e s a s c e n t r a l places p e r f o r m i ~ gcoinpreheneive services f o r a surrounding area. 2. C i t i e s a s transport f o c i and break of bulk points. 3. Specialized function c i t i e s performing one servicc such a s mining, maufacturing, or recre?.<ion f o r large &reas. More r e c e n t l y Redfield and Singer 80. introduced another c l a s - s i f i c a t i o n of c i t i e s . Discussing the c u l t u r a l r o l e of c i t i e s , they rec- ognized two types of c i t i e s : 1. C i t i e s of orthogenetic transformation. These are of the r u r a l order of culture c a r r i e d forward. .... 2. C i t i e s of heterogenetic transformation. These are c i t i e s of t h e t e c h n i c a l order, where l o c a l cultures are d i s i n t e g r a t e d and new integrations of society a r e developed .... I n addition, these authors recognized two p a t t e r n s of urbanization, primary and secondary. I n the primary phase a p r e c i v i l i z e d folk society i s t r a n s - formed by w b m i z a t i o n i n t o a peasant s o c i e t y w i t h correlated urban centres. This process takes place almcst e n t i r e l y within the framework of a core c d t u r e t h a t develops i n an indigen&s c i v i l i z a t i o n . Secondary urbanizaticjn follows primary wbanization when a f o l k society, p r e c i v i l i z e d , peasant, or p a r t l y urbsnized, i s f u r t h e r urbanized by contact with peoples of widely different cultures from t h a t of i t s own members. - 44 , Hoselitz, 81 r e c o ~ i z e sy e t another s e t of c i t i e s on the b a s i s . o f t h e i r r o l e i n the economic development of an area. According t o him a c i t y i s generative i f i t s continued existence and gro&h i s one of the f a c t o r s accountable f o r the economic development of the area i n which it It i s p a r a s i t i c i f it e x e r t s ail opposite impact. i s located. . I Further i n an attempt t o t i e together h i s ideas with those of Redfield and Singer, he observes t h a t although orthogenetic c i t i e s tend t o l i m i t i f not impede c u l t u r a l change, t h i s does not mean t h a t orthogenetic c i t i e s axe neces s a r i l y p a r a s i t i c with regard t o economic growth. Further, the process of primary urbanization, though leading t o a reinforcement of e x i s t i n g c u l t u r a l p a t t e r n s , may be generative of economic growth. I n t h e same way c i t i e s i n c e r t a i n stages of secondary urban- i z a t i o n may e x e r t an unfavora,ble e f f e c t upon economic growth of the wider geographical u n i t of,which they form a part. of colonial c i t i e s . An example i s t h a t I n a similar vein, Berry points out t h a t the process of secondary urbanization e x e r t s i t s e l f when an integrated system of c i t i e s develops, usually under t h e influence of forces external t o the l o c a l cul- ture. ... i n complex nodal systems of Heterogenetic c i t i e s r e s u l t economic organization characterized by r a p i d s o c i a l change. 82 How relevant are these notions t o an understanding of Indian c i t i e s ? Do Indian c i t i e s f a l l i n t o one of the four possible classes a s mentioned by Hoselitz in h i s discussion of generative and p a r a s i t i c c i t i e s ? 83 I n t h e opinion of many students of Indian urbanization, Indian c i t i e s , l i k e t h e i r counterparts i n t h e Western world, a r e centres of heterogenetic transformations and a r e generative of economic growth. Also, the-prevelent pro- cesses of urban growth i n India display a p a t t e r n which i s considered as secondary urbanization. This of course i s not intended t o imply t h a t there a r e no d i f ferences between the p a t t e r n of Indian urbanization, what ever it may be, and the urban p a t t e r n s t h a t e x i s t i n the Western world. During the past decade a number of studies have appeared which deal s p e c i f i c a l l y with urbanization i n the non-Western world. , 84 The authors of these works suggest t h a t urbanization i n Asia may involve q u i t e d i f f e r e n t patterns of development and inter-relationships with economic development than those observed i n the West. Some of the major differences indicated by them are: 1. Urban deirelopnent i n many countries of Asia i s l s r g e l y an' outgrc~wthof colonialism. 2. There i s an increasing r o l e of c e n t r a l planning and governmental interventionism i n Asian economic development. 3. There are g r e a t differences i n b a s i c outlook and value systems between Asia and the West. 85 Although Indian urbanization shares most of the c h a r a c t e r i s t i c s common t o other developing nations, it nevertheless has some d i s t i n c t i v e features. To begin with, India has a long urban t r a d i t i o n which goes back more than a thousand years. Unlike many countries of the non-Western world, I n d i a has a well-developed urban hierarchy so f a r as c i t y s i z e d i s - t r i b u t i o n i s concerned. ,There i s ample evidence t o the e f f e c t t h a t r u r a l - urban migration i s the most important f a c t o r contributing t o urbanization . i n I n d i a and t h i s migration i s d i r e c t e d not only towards t h e very l a r g e c i t i e s but a l s o t o hundreds of medium-sized and smaller c i t i e s i n almost a l l regions. Furthermore it has been arbued t h a t urbanization i s n e i t h e r a necessary nor a s u f f i c i e n t condition f o r economic growth. For these reasons and many others a policy of decentralization has been advocated i n India. The c m f l i c t between c e n t r a l i z a t i o n and a l t e r n a t i v e forms of decentralization i s a t the moment a very r e a l issue i n India. 86 One aspect of t h i s i s the posing of t h e problem a s a choice between two d i f f e r e n t p s t t e r n s of economic development, one v i l l a g e based and t h e other urban based. The balance between i n d u s t r i a l ' growth and urban devel- opment, the postulates of e q u a l i t y between r u r a l and urban standards of d costs and b e n e f i t s of regional d i s p e r s a l of industries, l i v i n g , a ~ the a r e the elements t h a t make decentralization a r e a l but s t i l l undecided issue. Due t o r a p i d population which has l e d t'o pressure on t h e urban centres and stagnation of the r u r a l economy, r a p i d urbanization has tended t o precede r a t h e r than follow i n d u s t r i a l i z a t i o n , leading t o a wide "development gap". "over urbanization" It appears i n two d i f f e r e n t forms, i n the form of i.e . urbanization exceeding the range of economic development, and i n t h a t of a marked deficiency of urban f a c i l i t i e s and services. 87 I t i s f o r these reasons t h a t Indian planning p o l i c i e s h m e tended t o concentrate on decentralization and f o s t e r the growth of medium s i z e d towns. 88 J . P . Lewis, i n a study of the o v e r a l l economic problems of Indian d e v e l h e n t argues t h a t there i s not: ... a s usual discussions sometimes seem t o suggest, any lack of medium s i z e d centres lying between v i l l a g e s , on the one hand, and t h e l a r g e r c i t i e s on the other. Instead, throughout t h e c i t y s i z e d i s t r i b u t i o n there presently are bases upon which f u r t h e r concentrations of a c t i v i t i e s of population could be b u i l t . 89 I India, it appears, although it does have a log-normal d i s - t r i b u t i o n , s u f f e r s from many serious s o c i a l and economic urban problems. Planning p o l i c i e s have been.directed.towards reducing the s i z e of the l a r g e s t c i t i e s , and f o s t e r i n g the growth of the medium sized towns. If the hyyothesis i s correct, t h a t the log-normal d i s t r i b u t i o n i s an optimm c i t y s i z e d i s t r i b u t i o n , then t h i s policy would oniy l e a d t o a non-optimal d i s t r i b u t i o n of c i t y s i z e . Lewis' observation on the c i t y s i z e d i s t r i b u t i o n in I n d i a would tend t o support t h i s hypothesis, It i s impossible t o a r r i v e a t any d e f i n i t e conclusions on the v a l i d i t y of a decentralization policy i n r e l a t i o n t o the log-normal d i s t r i b u t i o n without f u r t h e r analysis, so a t t h e present time the question of whether o r not the e x i s t i n g d i s t r i bution i s an opt5murn.i~s t i l l open. It could be argued t h a t the present d i s t r i b u t i o n minimizes the socio-economic forces acting on it t o change despite the f a c t t h a t these forces appear t o be very large. Any other d i s t r i b u t i o n may conceivably, increase the serious s o c i a l and economic problems i n t h e urban centres. This conclusion i s a l s o unverifiable a t the present moment, but it i s i n t e r e s t i n g t o keep i n mind. -- IX. CONCLUSION There i s considerable t h e o r e t i c a l support i n the l i t e r a t u r e f o r t h e hypothesis t h a t t h e log-normal ( o r rank-size) d i s t r i b u t i o n i s an "optimum", steady-state or s t a t i s t i c a l equilibrium d i s t r i b u t i o n , under cert a i n conditions ( c f . the Pareto d i s t r i b u t i o n ) . The existence of the log- normal d i s t r i b u t i o n f o r c i t y s i z e s i n both underdeveloped and developed countries, appears t o be the r e s u l t of the i n t e r a c t i o n of numerous comp e t i t i v e f o r c e s over a long period of time. I n India, f o r exmple, the log-normal d i s t r i b u t i o n has evolved during a long h i s t o r y of urbanization. The' primate d i s t r i b u t i o n , which shows the g r e a t e s t deviation from the lognormal, r e s u l t s from the dominance of a small number of very large forces c i t i e s s u f f e r f r o x problems E imilar t o produce t h i s d i s t r i b u t i o n . Pr-%n&e. t o the l a r g e s t c i t i e s i n the log-narmal d i s t r i b u t i o n , but t o a much g r e a t e r extent. The r e j e c t i o n of an approach based or-,net urban economies t o analyze t h e optimum c i t y s i z e , i s reasonable when taken i n the context of a systems approach t o c i t y s i z e d i s t r i b u t i o n s . General systems theory, incorparating s t o c h a s t i c growth theory, appears t o be a meaningffil way of' examining the problem of an optimum c i t y s i z e d i s t r i b u t i o n , since it focuses a t t e n t i o n away from single optimizing c r i t e r i a , and more tmiard the whole of the d i s t r i b u t i o n . It i s evident t h a t t h e r e a r e many problem i n t e s t i n g the hypothesis t h a t the log-no:(-ma1 d i s t r i b u t i o n i s an optimum. In t h e case of India, with a log-normal c i t y s i z e d i s t r i b u t i o n , many s o c i a l and economic problems face i t s c i t i e s , which appear t o be almost insoluble. Considerable work must be undertaken before it can be f i r m l y e s t a b l i s h e d t h a t any one type of d i s t r i b u t i o n i s an optimim under a w2de v a r i e t y of conditions, although it appears t h a t a t h e o r e t i c a l f'ramework has evolved which may be a useful a n a l y t i c a l approach t o t h e general problem of optimum c i t y s i z e d i s t r i b u t i o n . REFERENCES E. Howard, Garden C i t i e s of Tomorrow o on don: Faber and Faber Ltd., 1946). F.J. Osborn, Transport, Town Development and T e r r i t o r i a l Planning of Industry No. 20 (London: The New Fabian Research Bureau, Vict o r Gollancz, Ltd., 1934), p . 20. Lewis Mumford, The Culture of C i t i e s ( ~ e wYork: Harcourt Brace, 1938), p . 488. ' ~ r a c B. ~ Augur, "The Dispersal of C i t i e s a s a Defense Measure", l e t i n of t h e Atomic S c i e n t i s t s , Vol. IV, May, 1948, pp. 131 % a l t e r Tsard, Location and Space Econoq ( ~ e wYork: Sons, Inc., 1956), esp. pp. 182 - 188. Bul- - 134. John Wiley and , 4 ~ o r r e s tP i t t s , Urban Systems and Economic Development ( ~ u ~ e n eOregon: University of Oregon, School of Business Administration, 1962). 5 ~J..L. Berry, 'see "City Size Distributions and Economic Development", Economic Development and Cultural Change, Vol. 9, 1961, pp. 537 588. Reprinted i n J. Friedmann and W i l l i a m Alonso, Regional Development and Planning (cambridge, Mass. : The M. I. T. Press, 1964). Berry's work was based on data p r e s e n t e d i n N . Ginsburg, A t l a s of Economic Development (Chicago: 1961). George K . Zipf, Human Behavior and t h e Principle of Least E f f o r t (cambridge: Addison-Wesley Press, 1949). Jefferson, "The I a w of t h e Primate c i t y " , Review, XXXM, 1939. The Geographical 8 ~ t a l y , Finland, Belgium, U. S .A. , Poland, West Germany, Switzerland, I n d i a , Korea, China, B r a z i l , E l Salvador, Union of South Africa. 9 ~ r e e c e ,Austria , Spain, Denmark, Netherlands, Sweden, Portugal, Uruguay, Peru, Guatemala, Mexico, Dominican Republic, Thailand, Jtipan, Ceylon. 1•‹parkis t a n , Malaya, Nicaragua, Ecuador, Yugoslavia, ~ o r w & , Englsnd and Wales, A u s t r a l i a , Canada, New Zealand. l l g e r r y , op. c i t . , p. 585. 12'I'he other major findings of Berry ' s study were: I On t h e log-normal d i s t r i b u t i o n . m ~ i s tnoticeable t h a t countries with long urban tradTtions such a s India and China, and highly developed countries such a s the United S t a t e s and Germany have very s i m i l a r distributions." 'On t h e primate & s t r i b u t i o n . h ~ fli l f t e e n of the countries with primate c i t y d i s t r i b u t i o n were small and they range from underdeveloped Thailand through countries with dual and peasant economies t o Denmark and t h e Netherlands with highly specialized a g r i c u l t u r a l economies." Primacy was considered t h e simplest c i t y s i z e d i s t r i b u t i o n and affected by only a few simple but dominant forces. The rank s i z e d i s t r i b u t i o n however a r i s e s out of a compl-exity of competing economic, s o c i a l , and p o l i t i c a l forces over a long period of time. 11 There i s no r e l a t i o n s h i p between type of c i t y s i z e d i s t r i b u t i o n and t h e degree t o which a country i s urbanized. Countries which have u n t i l recently been p o l i t i c a l l y and/or economicalii dependent upon some outside country tend t o have primate c i t i e s >~hicha r e t h e n a t i o n a l c a p i t a l s , c u l t u r a l and economic centres, often the chief p o r t , and t h e focus of n a t i o n a l consciousness and feelLng." The model i n e f f e c t proposes a major hypothesis, t h a t i s , i r ~ c r e a s e d entropy i s accompanied by a c l o s e r approximation of a c i t y s i z e d i s t r i b u t i o n t o log-normality. This leads t o f u r t h e r sub-hypotheses namely t h a t (1) t h e smaller t h e country i s and ( 2 ) t h e s h o r t e r i s t h e h i s t o r y of urban l i f e i n t h a t country and ( 3 ) t h e lover and hence simpler i s the l e v e l of economic and p o l i t i c a l development i n the country, t h e fewer w i l l be t h e forces a c t i n g on t h a t country's c i t i e s . Hence a s t h e l e v e l of economic development increases, t h e l e v e l of complexity of c i t y d i s t r i b u t i o n increases. This l e d B e r ~ yt o consider t h e r e l a t i o n s h i p between r e l a t i v e l e v e l s of economic development and c i t y s i z e d i s t r i b u t i o n s . Forty-five indices of economic development, based on transportation, energy, a g r i c u l t u r a l y i e l d s , communications, G.R.P., trade,demographic and other data, were reduced t o four basic ~1.9tternsof economic development, based on ( i ) technological, ( i i ) demographic, ( i i i ) trading, and ( i v ) s i z e of country c h a r a c t e r i s t i c s . (i)and ( i i ) were f u r t h e r reduced t o a s c a l e of economic-demographic development, which was r e l a t e d t o %he types of c i t y s i z e d i s t r i bution. Furthermore it was found t h a t "clifferent c i t y s i z e d i s t r i butions a r e i n no W ~ J T r e l a t e d t o t h e r e l a t i v e economic development of countries". Hence primacy i s not r e l a t e d t o l e v e l of urbaniza t i o n of a country, since l e v e l of urbanization and l e v e l of economic development a r e highly correlated. There i s no ready explana t i o n i n t h e l e v e l of economic development, f o r v a r i a t i o n s i n c i t y s i z e d i s t r i b u t i o n s on a scale from simple s t r u c t u r e (primary) op. c i t . , p. 572 e t seq. t o entropy (log-normality). , '%.w. Singer, "The 'Courbe des Populations1: a P a r a l l e l t o Pareto's Law1', Economic Journal, Vol. 46, 1936, pp. 254 - 263. 14'lhis screening process i s a l s o known a s t h e "Law of P r ~ p o r t i o n a t e~ f f e c t " . 15see D.G. Champernowne, "A Model of Income ~ i s t r i b u t i o n , " Econoluic Journal, Vol. 63, pp. 318 e t seq. ... 16Champernowne mentions t h e " impossibility of drawing any simp l e conclusions about the e f f e c t on P a r e t o t s 6 ( o f various r e d i s ", I b i d . , p. 319. tributive policies .... . 17singer, op. c i t , p. 260. See a l s o G.R. Allen, "The 'Courbe des Populations'. -9 Further Analysis", B u l l e t i n of t h e Oxford I n s t i t u t e of S t a t i s t i c s , Vol. 18, 1954, PP 179 - 189. 1 8 ~ l l e nf i t t e d t h e Pareto formula t o 44 countries and finds: It The main conclusions a r e therefore t h a t t h e Pareto law can be u s e d w i t h much success t o summarize t h e r e l a t i o n s h i p between s i z e of towns and number of towns above a s p e c i f i e d s i z e ( 2 , 0 0 0 ) " ~ Ibid - 9 P * 184. l9zcPf, op. c i t . , *Ozipf, I b i d . , p. 376. p . 264. 2$. J. L. Berry and W. L. Garrison, "Alternate Explanations of Urban Rank-Size Relationships1', Annals of t h e Association of American Geographers, Vol. 47, 1958, pp. 83 - 91. 2 2 ~ s a r d ,op. c i t . , p. 57. 23~.~ Stewart, . "The Size and Spacing of c i t i e s " , Review, Vol. 48, 1958, pp. 222-242. Ihe Geographical 2 4 ~ e ea l s o Kenneth E. Rosing , "A Rejection of the Zipf Model ( ~ a n k Size ~ u l )e i n elation-to City s i z e " , The ~ r o f e s s i o n a lGeogrzpher v o l . 18, NO. 2, 1966, pp. 75 - 82. , 2h. Chri s t a l l e r , Die Zentralen Orte i n Suddeuhschland ( ~ e n:a Gustav Fischer, 1933, t r a n s l a t e d i n 1954 a t t h e Bureau of Population and Urban Research, University of Virginia, by C Baskin. ) . . 2 6 C h r i s t a l l e r ' s k = 3 network was t h e optimum p a t t e r n of hexagonal networks organized according t o a marketing p r i n c i p l e . For t h e t r a n s p o r t p r i n c i p l e t h e optimum network was k = 4 , f o r t h e administrative ' p r i n c i p l e k = 7. 2 7 ~ e r r yand Garrison, op. c i t . , p . 86. 2 8 ~ e eRutledge v i n i n g , "A Description of Certain S p a t i a l Aspects of an Economic System", Economic Development and Cultural Change, Vol. 3, 1955, pp. 147 - 195. Vining argues t h a t "The a n a l y t i c a l problem i s not t h a t of determining an 'optimum' o r 'economical' . s p a t i a l o r i e n t a t i o n of c i t i e s . Rather it i s t h a t of analyzing a p r o c e s s i m p l i c i t i n a sequence of i n d i v i d u a l a c t i o n s performed w i t h i n a s p e c i f i e d system of c o n s t r a i n t s . The c h a r a c t e r i s t i c s of t h i s process a r e among t h e r e l e v e n t f e a t u r e s t o be considered." 2%"I'e considerable degree of empirical correspondence t o t h e rank: s i ze w suggest t h e p r o p o s i t i o n t h a t t h e populations r u l e f o r population m of c i t i e s t e n d t o be d i r e c t l y r e l a t e d t o t h e i r maximum h i n t e r l a n d s . ., 30~hampernowne, op. c i t p. 318. 3 1 ~. A . S t o u f f e r , " ~ n t e r v e n i n gOpportunities : A Theory R e l a t i n g Mobi l i t y and Dlstance", American S o c i o l o g i c a l R'eview, Vol. 5, 1940, pp. 845 - 868. 3*The Yule D i s t r i b u t i o n i s a g e n e r a l term f o r t h e log-normal types o f d i s t r i b u t i o n , and includes t h e log-lognormal d i s t r i b u t i o n . 3 3 ~ e ea l s o H.A. Simon, "On a Class of Skew D i s t r i b u t i o n F'unctions", Biometrika, Vol. 42, 1955, pp. 425 - 440. Also r e p r i n t e d a s Chapter 9 i n Models of Man (New York: John Wiley and Sons, Inc 1957) 34The n o t a t i o n used i s t h a t of Berry and Garrison, op. c i t . , pp. 86 ., - 89. ~ E . N . Thomas, "Additional Comments on Populatibn-Si ze Relationshius &d f o r sets-of Citiest1~.n Q u a n t i t a t i v e ~ e o ~ r a W~.L. h ~Garrison , D.F. Marble (eds (hranston, Ill. : Northwestern University S t u d i e s i n Geography #3, 1967) . 37This i s t h e "Law of Proportionate ~ f f e c t " ,mentioned e a r l i e r ( s e e p. l o ) , i.e. 'A v a r i a t e s u b j e c t t o a process o f change i s s a i d t o obey t h e Law of Proportionate E f f e c t i f t h e change i n t h e variaJie a t any s t e ~ of t h e process i s a random proportion of t h e previous value of t h e v a r i a t e . ' ' See J. Aitchison and J.A.C. Brown, The Log-Normal Dist r i b u t i o n (cambridge: The University Press, 1967), p . 22. 3 8 ~ o m a s , op. c i t . , p. 179. 39M. Kalecki , "On t h e Gibrat D i s t r i b u t i o n " , Econometrica, Vol. 13, 1945, pp.. 161 - 170. 4 0 ~ . ~Madden, . "On Some I n d i c a t i o n s of S t a b i l i t y i n t h e Growth of C i t i e s i n t h e U.S.", Economic Development and C u l t u r a l Change, Vol. 4, 1956, pp. 236 - 253. 1 41~. Vining, "Regional V a r i a t i o n i n C y c l i c a l F l u c t u a t i o n Viewed a s a Frequency D i s t r i b u t i o n " , Econometrica, J u l y 1945, Vol. 4 , ~ p ~. 8 -7 188. 42The log-normal d i s t r i b u t i o n i s a l s o shown t o h o l d f o r t h e p o ~ u l s t i o n d e n s i t y p a t t e r n of c i t i e s . .See B.J.L. Berry, "The I n t e r n a l S t r u c Lure o f t h e c i t y " i n Urban Prospects and Problems, Law and Conte;nporary Problems Vol. XXX, 1965 (school of Law, Duke University, North ~ a r o l i n ja pp 111 - 119. See a l s o H.H. Winsborough, "City Growth and City s t r u c t u r e " , J o u r n a l of Regional Sciences, Vol. 4, 1963, who argued t h a t i e a s u r e s of concentration of t h e c i t y ' s population and of congestion c f c i t i e s can be derived from t h e log-normal d i s t r i b u t i o n a s a p p l i e d t o c i t y s i z e s and t o urban population d e n s i t i e s . . , 4 3 ~ l b e r t0. Hirschman, The S t r a t e g y of Economic Development and London: Yale University Press, 1958). ( ~ e wHaven ' 4 4 ~ e eL. Curry, "Explorations i n Settlement Tneory: The Random S p a t i a l Econoqy, P a r t l", Annals of t h e Association of American Geographers, Vol. 54, 1964, pp. 138 - 146. 4 % . ~ . Simon and C.P. Bonini, "The S i z e D i s t r i b u t i o n of Business Firms", American Economic Review, Vol. 48, 1958, pp. 607 - 617. 47This assumption i s j u s t i f i e d on t h e b a s i s t h a t s i n c e t h e r e e x i s t s cons t a n t r e t u r n s t o s c a l e above a c r i t i c a l minimum s i z e of firm, it i s '!natural t o expect t h e firms i n each c l a s s s i z e t o have t h e same chance on t h e average of i n c r e a s i n g o r decreasing i n s i z e i n proport i o n t o t h e i r p r e s e n t s i z e . " This i s t h e Law of Proportionate E f f e c t P - 609. a s mentioned before. I b i d -, 4 9 ~ e eSimon, 0 . c i t . ; pp. 427 - 4.30. 5 0 ~ i t c h i s o nand Brown, op. c i t . , pp. 111 - 5'1t 116. ti~ veness i s a l s o apparent t h a t p i s a measure of t h e degree of ~ o mop+.i + i n t h e system, a s p - 3 2 , t h e competitiveness a l s o i n c r e a s e s . Analogies with c i t y s i z e d i s t r i b u t i o n s a r e immediately apparent. 52~imonand Bonini 5 3 ~ e r r y , op. c i t . , 5 4 ~ . ~Neutze, . , op. cit ., p. 616. p. 575. Econonic Policy and t h e S i z e of C i t i e s t r a l i a n National University, 1965). ( ~ a n b e r r a :The Aus- , 5 5 ~ b i d . pp. 37 - 38. 5 6 ~..Scitovsky , "Two Concepts of External ~ c b n o m i e s ~ Journal , oS Poli t i c a l Econoqy, Vol. 63, 1955, pp. 446 - 449. 5 7 ~ . ~Stockfish, . " ~ x t e r n a lEconomies, Investment and Foresight", Journal of P o l i t i c a l Econoqy, Vol. 62, 1954, pp. 143 - 151. %.z. Hirsch, " ~ e a s u r i n gFactors Affecting Expenditure Levels of Local Goverment Services", Metropolitan S t . Louis Survey, S t . Louis, 1957. 5 9 ~ . ~Lomax, . "The Relationship Between Expenditure Per Head and Size of Population of County Boroughs i n England and Wales", Journal of Royal S t a t i s t i c a l Society, Vol. 106, 1943, pp. 51 - 59. 60There have been many studies of t h e r e l a t i o n s h i p of expenditures t o c i t y s i z e s especially i n t h e U.S. Among t h e more important are: W.Z. Hirsch, "Expenditure Implications of Metropolitan Growth and Consolidation", The Review of Economics and S t a t i s t i c s , Vol. 41, 1959, pp. 232 241. H.E. Brazer, City Expenditure i n t h e U . S . , (Few York: National Bureau of Economic Research, 1959). J. Marg o l i s (ed.) The Public Econoqy of Urban Communities ( ~ a l t i m o r e : Resources f o r t h e Future Inc John Hopkins Press, 1965). - ., , 61~sard, op. ci?:.. pp. 57 '%adden, op. c i t . , pp. - 58. 247 - 249. 6 5 ~ e r w , op. c i t . , p. 582. %r example, Simon, op. c i t . , pp. 427 P * 319. - 428 and Champernowne, op. c i t . , 6 7 ~ .Vining, . "A Description of Certain S p a t i a l Aspects of an Economic syster;l", ~conomic-Development and c u l t u r a l Change, Vol. 3, 1954- 5, pp. 147 - 195. E.M. Hoover, "The Concept of a System of C i t i e s : A Comefit on Rutledge ~ i n i n g ' sPaper", Economic Development and . ~ u l t u r i Change, l Vol. 3, 1954-5, pp. 196 - 198. @B.J.L. Berry, " c i t i e s a s Systems Within Systems of c i t i e s " , Pa e r s of t h e Regional -Science Association, Vol. 13, 1964, pp. 147%@The concept of ectropy originates i n the second Lair of Thermo@namics. If two systems with entropy S1 and S2 a r e u n i t e d then S1 = S2 = S. The entropy of a closed p h y s i c a l system tends t h e r e f o r e t o increase a s l o n g a s t h e system has not y e t reached equilibrium and entropy may t h u s be taken a s a measure of t h e degree of e q u i l i z a t i o n reached w i t h i n a system. Entropy of a closed system i s maximized when t h e system i s i n equilibrium. Boltzmann's Law of Entropy argues t h a t lower temperature should be understood a s a s t a t i s t i c a l e q u a l i z a t i o n of d i f f e r e n c e s i n molecular speed. Let p h y s i c a l entropy S = T o g , + R / m l o g ~ --------------. (1 Where . . V = Volume of gas whose mass equals 1 u n i t . C, = S p e c i f i c heat; at constant volume. T = Absolute temperature. m = Molecular weights of t h e gas. R = General gas constant. f-l r\ Where pi = p r o b a b i l i t y of f i n d i n g an i d e a l i z e d physical system i n t h e s t a t e i of n p o s s i b l e s t a t e s , and k = a c o n s t a ~ t . - Now t h e p r o b a b i l i t y t h a t molecules i n a gas container can be d i s t r i b u t e d among n p o s s i b l e s t a t e s i n p ways i s : Thus i f t h e system i s l a r g e t h e n : s \ = l o g p = plogp - . n Thus s i n c e S = -k pilogpi S = -k(plogp ------------------ (4) i=l L pilogpi-k(logpi) /=I Then 2 n -2 pilogpi) ------------------ ( 5 + C -------------- ( 6 ) i= 1 (4) and (5) both hold only i f 2k = 1 70 Berry and Garrison, op. &it ., p. 89. 71 ~ u r m ,op. c i t ., p . 144. T 2 M. Maruyama, "The Second Cybernetics : Deviation Amplifying Mutua3. Causal Processes", American S c i e n t i s t , V O ~ . 51, 1963, pp. 164-179. 73 Morphostasis i-s a ships ... . I1 "... d e v i a t i o n counteracing mutual causal r e l a t i o n See Marujrama, op. c i t ., p . 1 6 h - 7 4 ~ .I@rdal, ~ c o n o m i cTheory and Underdeveloped Regions 75 Maruyama, op. c i t . , % b i d . , p . 165 - pp. 167 - on don: 1954). 168. 166. C f . Myrdal's v i c i o u s c i r c l e concept. 7 7 measure ~ of order may be R H' /H) where H = maximum entropy i n a system under no s t r u c t u r a l r e l a t i o n s ( i . e . i n d i v i d u a l s i n i s o l a t i o n ) . H ' = maximum entropy i n a system with a given l e v e l of s t r u c t u r a l r e l a t i o n s . Hence 05R 51 a r e two l i m i t i n g cases. When R = 0 then H ' = H ( i . e . no s t r u c t u r e exists)', when R = 1 then H ' = 0 and a system i s developed i n t o a s i n g l e l i g h t l y c l u s t e r e d web of a c t i v i t i e s . Now i n a c l o s e d p h y s i c a l system, entropy w i l l i n c r e a s e with time and order decrease. However, a s e l f - o r g a n i z i n g system w i l l by d e f i n i t i o n be i n c r e a s i n g order and decreasing entropy. See Curry, op. c i t . , p . 145. 7 8 ~ u r r y , op. c i t . , p . = 1-( 145. 7 9 ~ . ~H a. r r i s and E.L. Ullman, "The Nature of C i t i e s " , Annals of t h e American A c a d e q of P o l i t i c a l and S o c i a l Science, V a l . 242, Nov. 1945, PP. 7 - 17. 8 0 ~ o b e r tR e d f i e l d and Milton Singer, "The C u l t u r a l Role of C i t i e s " , Economic Development and C u l t u r a l Change, Vol. 3, 1954,.pp. 53 81J3.~. - 73. H o s e l i t z , "Generative and P a r a s i t i c C i t i e s " , Economic Development and C u l t u r a l Change, Vol. 3, A p r i l 1955, pp. 278 - 294. 8 2 ~J.. L. Berry, "Urban Growth and Economic Development of Ashanti", i n F o r r e s t P i t t s (ed. ), Urban Systems and Economic Development, pp. 52 54 8%Ioselitz, op. c i t . , p . 280. 8 4 ~ a r s i c u l a r l yi n t e r e s t i n g , a s w e l l a s of g r e a t informative value a r e t h e proceedings of t h e two seminars on urbanization i n Asia and L a t i n America sponsored j o i n t l y by t h e United Nations and i t s agencies. See P.M. Hauser (ed. ), Urbanization i n Asia and t h e F a r East (ECAFE Region, Bangkok, 8 - 18 August, 1956, C a l c u t t a , 1957). P.M. Hauser ( e d . ) , Urbanization i n L a t i n America (UNESCO,Santiago, Chile, 6 18 July, 1959, New York, 1961). 8 5 ~ . ~McGee, . The Southeast Asian City ( ~ e wYork: F.A. Praeger, 1967). See a l s o P.M. Hauser, Urbanization i n Asia and t h e Far E a s t , p. 31. 8 6 ~ .H ~ o. s e l i t z , "A Survey of t h e L i t e r a t u r e of Urbanization i n ~ n d i a " , : of i n Roy Turner (ed. ) I n d i a ' s Urban Future ( ~ e r k e l e ~ University C a l i f o r n i a Press, 1962), pp. 425 - 443. , - 8 7 ~ e eN.V. Sovani, "The Analysis of Over-Urbanization" , EconmZc Development and Cultural Change, Vol. 12, No. 2, 1964. See a l s o N.V. Sovani, Urbanization and Urban India ( ~ e wYork: Asia Pu3lishing House, 1966). Also J.F. Bulsara, Problems of Rapid Urbanization i n India omba bay : Popular Prakashan , 1964). 8 8 ~ . ~Lokanathan, . "Market Towns and S p a t i a l Development i n lndial' National Council of Applied Economic Research ( ~ e wDelhi 1 9 6 5 3 "J.P. , Lewjs, Quiet C r i s i s i n India (washington, D. C. : The Brookings I n s t i t u t e , 1962). Especially Chapter 7 "The Role of t h e Town i n ~ n d u s t r i a lLocation". Aitchison, J . and Brown, J. A . C. bridge: The University Press, The Log-Normal Distribution. 1957. Bra'ze.r,'-Ei, E. . City Expenditure i n t h e United S t a t e s . i o n a l Bureau of Econonic Research, 1959). (New York: Friedmann, J. and Alonzo, W . - - bridge, Garrison, W .L. 1967) (ed. ) ( ~ e n a : Gustav Regional ~evelopmentand Planning. Mass. : The MIT Press, Nat- omba bay : Bulsara, J. F. Problems of Rapid Urbanization i n India. Popular Prakashan, 1964). C h r i s t a l l e r , W. Die, Zentralen Orte i n Suddeutschland. Fischer, 1933). C2n- (cam- 1964). Q u a n t i t a t i v e Geography. (New York: Atherton Press, Hauser, P. and Schnore, L.F. (eds. ) The Study of Urbanization. York: John Wiley and Sons, 1nc. 1965). , (~ew Hauser, P. (ed. ) Urbanization i n Latin America. (New York: Proceedings of UN seminar on Urban Problems i n Latin America; UNESCO, Santiago, Chile, 6 - 18 Jdy, 1959; 1961). Hauser, P. (ed. ) Urbanization i n Asia and t h e Far East. ( ~ a l c k t t a : ECAFE: Regional Seminar, Bangkok, 8 - 18 August, 1956; 1957). Hirschman, A. 0 . The Strategy of Economic Development. University Press, 1958). Howard, E. Garden C i t i e s of Tomorrow. I s a r d , W . Location and Space Economy. ,1956). ondo don: (New York: (New Haven: Yale Faber and Faber, 1964). John Wiley and Sons, Lakanathan, A.K. Market Towns and Slmtial Development i n India (New Delhi : National Council of Applied Economic Research, 1951). Lewis, J.P. Quiet C r i s i s i n India. I n s t i t u t e , 1967). (washington D.C. : The Brookings Margol.is, J . (ed. ) The Public Econon~yof Urban Communities. f o r Future, Baltimore: John Hopkins Press, 1965). (~esources 8 McGee, T.G. The Southeast Asian City. Mumford, Lewis. The C ~ f i t u r eof C i t i e s . (New York: (New York: F.A. Praeger, 1967). Harcourt-Brace, 1938). Myrdal, Gunnar. Economic Theory and Underdeveloped Regions. George Allen and Unwin 1954) , . Neutze,G.M. Economic Policy and t h e S i z e of C i t i e s . A u s t r a l i a n National University, 1965). ondo don: ( ~ a n b e r r a ,The e, : P i i t s , F o r r e s t R. Urban Systems and Economic Development. ( ~ u ~ e n Ore. U n i v e r s i t y of Oregon, School of Business Administration, 1962). Simon, H.A. Sovani , N.V. House, Models of Man. ( ~ e wYork: John Wiley and Sons, Inc Urbanization and Urban I n d i a . ( ~ e wYork: ., 1957). Asia Publishing 1966). Turner, Roy (ed. ) I n d i a ' s .Urban Future. i f o r n i a P r e s s , 1962). ( ~ e r k e l e :y University of Cal- , -