Experimental Design

advertisement
Nested Designs: Field and
Natural Experiments and the
Role of Qualitative Methods
Thad Dunning
Department of Political Science
Yale University
Prepared for the Short Course on “Nested Research Designs” sponsored by the
Organized Section on Qualitative and Multi-Method Research, APSA 2009
Plan for the talk
•
Using nested designs to strengthen causal inference,
in a comparative project on cleavage structures
•
Two examples:
• Cross-Cutting Cleavages and Ethnic Voting in Mali: A Field
•
•
Experiment
The Salience of Caste Categories in India: Nesting a Field
Experiment within a Natural Experiment
Two of the key points:
• Qualitative methods play a central role
• External validity concerns arise in both studies; combining
experimental and observational data to address them
•
Practical issues: how feasible are such studies?
Example 1: Cross-Cutting Cleavages and Ethnic Voting
• Do cross-cutting cleavages—that is, dimensions of
identity or interest along which members of the same
ethnic group have diverse allegiances—limit ethnic
voting?
•
Classic insights have been extended in the recent
comparative politics and political economy literature
•
Yet estimating causal effects is difficult
Why no ethnic voting in Mali?
•
Mali is ethnically heterogenous
•
Yet parties do not form along ethnic lines
•
Unlike many sub-Saharan African countries, in Mali
ethnicity is a poor predictor of individual vote choice
•
One hypothesis: “cousinage”
• Malians with certain family names are linked through “joking
alliances” with their fictive cousins
• Two strangers -- say, a Keita and a Coulibaly -- may use
cousinage relations to establish rapport and limit interpersonal
conflict
Cousinage as a cross-cutting cleavage
• The key point: cousinage alliances cross-cut ethnic ties,
because they occur across as well as within ethnic groups
• Such cross-cutting alliances may weaken the correlation
between ethnicity and vote choice
• Imagine two voters with the same ethnic relationship to a
candidate but different cousinage relations: their preferences over
this candidate may diverge
• Dunning and Harrison (2008) use a field experiment to
study the effect of cousinage and co-ethnicity on
candidate preferences
• The experimental design can be applied in other contexts
Cousinage in brief
• Cousinage relations were codified during the rule of the
emperor Sundiata Keita (c. 1235-1255) and exist in Mali,
Sénégal, Guinea, the Gambia, the northern Ivory Coast,
and Burkina Faso
• Though various kinds of cousinage ties exist, we focus
here on cousinage alliances between patronyms
• Standard jokes are used to establish rapport with
“cousins” (though joking is by no means automatic)
• Our focus is not on explaining the origins or persistence
of cousinage alliances but rather on estimating their
causal effects
Experimental Design
•
Any voter and politician can be placed in this 2x2 table,
depending on their relationship with each other:
Joking cousins
Not joking cousins
Same
ethnicity
Different
ethnicity
•
In Mali, last (family) name conveys information about both
ethnic identity and cousinage relations, allowing the
classification of voter-politician pairs
Experimental manipulation
•
We filmed two Malians delivering an identical political
speech (in Bambara) and showed the speech to
Malian participants
•
We varied the last name of the politician across
different versions of the speech
•
Each subject was assigned at random, with equal
probability, into one of six treatment conditions:
• The four cells in the 2x2 table, plus:
• A “no name” condition
• A “same name” condition
Stimulus: The political speech
•
The content of the speech was intended to be typical of
speeches by candidates to the National Assembly
• Themes: need to improve infrastructure, education, electricity
•
56 percent of subjects said the speech “reminded them of
a speech they had heard on a previous occasion”
•
The use of Bambara, Mali’s lingua franca, does not imply
a particular ethnic identity for the politician
• Given politician’s last name, subjects correctly inferred ethnicity
•
•
more than 85 percent of the time, from 14 ethnic categories
When given no last name, their guesses roughly mirrored the
distribution of ethnic groups in Bamako
No difference between the two actors—one of whom was
ethnically Peulh, the other of whom was Bambara
Perceived Ethnicity of Politician 1, No Last Name Given
(Actor's True Ethnic ity: Peul)
.4
.3
.2
D
.1
Bam bara Snke Mali nke
Peu l Dogo n Bob o
ethnie _ca ndid at
Snfo Son ghai Dial o Tu areg
0
e
n
sit
Perceived Ethnicity of Politician 2, No Last Name Given
(Actor's True Ethnic ity: Bambara)
.5
.4
.3
D en
.2
sit y
.1
0
Bam bara Snke Mali nke Peu l Dogo n Bob o Snfo Son ghai Dial o Tu areg
ethnie _ca ndid at
Subject recruitment
• A door-to-door canvass in all of Bamako’s neighborhoods (quartiers)
• A convenience sample -- however, intended to be as representative
of Bamako as possible
• After subjects agreed to participate, we obtained initial subject data,
including last name and self-identified ethnicity
• Subjects were then randomized into one of six treatment conditions,
shown the video, and administered a post-speech questionnaire
Randomization of Treatment Assignment:
Creating a cousinage “map”
• A challenge: linking particular last names in the
cousinage system
•
Qualitative (open-ended, semi-structured) interviews
played a key role
•
We used the interviews and drew on the literature to
create a cousinage “map,” that is, a matrix:
• the rows of which list potential last names of subjects;
• the columns of which give last names associated with each
of the six treatment conditions
A typical row of the random assignment matrix:
(1)
(2)
(3)
Co-ethnic/
cousin
Co-ethnic/
non-cousin
Non-coethnic/ Non-coethnic/ No
cousin
non-cousin
name
Keita
(Maninka)
1. Sissoko
2. Konaté
1. Diané
1. Doucouré
2. Sacko
3. Sylla
4. Coulibaly
5. Touré
(4)
1. Diallo
2. Cissé
3. Dambelé
4. Théra
5. Dabo
6. Togola
7. Watarra
(5)
(6)
Same
name
Pas de nom
Keita
(Maninka)
• The final matrix has around 200 last names in the first column
(the names for potential subjects)
Randomization: creating a cousinage matrix
•
We had to revise the matrix after initial field trials,
using field interviews with informants as well as our
initial data to correct errors
•
An iterative process that very centrally involved
qualitative methods
•
Challenges:
• Expanding the left column to include sufficient last names
•
(for ease of subject recruitment)
Improving the match between random assignment and
subject perception
Weaknesses of the experimental design
•
Estimated treatment effects may not be large, for a number of
reasons
•
•
•
•
•
Stimulus is somewhat artificial?
May not prime ethnicity
May not prime cousinage
Measurement error
Turning to the analysis…
•
•
Intention-to-treat analysis
Can the experimental evidence explain the observational
relationship?
Average candidate evaluations, by treatment assignment
The figure displays average answers to the question: “On a scale of 1 to 7, how much
does this speech make you want to vote for (name of candidate)?”
The salience of ethnicity: qualitative evidence
•
Comments by experimental subjects as well as other field interviewers underscore
the social as well as political salience of ethnicity:
• An ethnic Bamanan subject: a politician named Guindo (an ethnic Dogon patronym)
could never do a good job
• An ethnic Bamanan subject: the Dogons “don't know how to lead.”
• An ethnic Songhai suggested that Bobo ethnics “don't know anything about politics,”
while an ethnic Malinké subject said the same of Dogons.
• An ethnic Soninké subject offered the opinion that “the Malinkés are not intelligent.”
• Subjects tended to offer more positive comments about co-ethnics.
•
Subjects were especially prone to praising politicians bearing their own patronyms:
• From a subject named Anne: “The Anne family is composed of intellectuals.”
• From one subject named Sacko: “A Sacko is a hard worker.” From another: “The Sackos
are very cultured.”
• From a Kouyate: “if a griot (Djely, Kouyate) is a candidate, it is because he is capable of
many things.
• From a Koné, explaining why she paid attention to the candidate’s last name: “The
Konés are nobles” (the Konés were members of the caste of nobles during the Mali
Empire)
• A subject named Keita, when asked whether she would be more susceptible of voting for
a candidate sharing her family name said “yes, like uncle IBK”—a reference to an
opposition candidate during the 2007 presidential elections, whose patronym is Keita.
The salience of cousinage: qualitative evidence
•
Comments from experimental subjects and other field interviewees
underscore the salience of cousinage alliances
•
Voters anticipate being able to make requests of as well as sanction their
cousins
•
•
•
•
•
•
“If (the politician/cousin) is not serious, we will correct him.” (Experimental subject,
explaining why she would be more likely to vote for a joking cousin)
“If the politican does not respect his promises, we will bring him to heel, because he
is a senanku (cousin).” (Experimental subject, explaining why he would be more
likely to vote for a joking cousin)
One can “never hurt (one’s) cousin and “one must do what (one’s) cousin asks.”
(Field interview)
Cousinage alliances “result in greater willingness to make voluntary material
sacrifices (of resources, time, willingness to voluntarily cede in disputes, etc.)”
(Galvan 2006)
“Voters tend to vote for their allies (cousins), saying that in case of problems—
administrative, political, or social—the elected ally would be more prompt to
intervene than he would be even with a direct member of his own family.” (Douyon
2006)
We cannot fully distinguish mechanisms that explain why cousinage affects
political preferences; however, trustworthiness and credibility appear to play
an important role
The Effect of Cousinage on Perceptions of Candidate Attributes
(Differences of Means, Cousins Minus Non-Cousins)
The figure reports the estimated effect of cousinage alliances on subjects’ evaluations of the candidate’s attributes.
All variables are rescaled to run from 0-1, so effect sizes are on that scale. The darkened circles give point estimates,
while vertical lines show 95% confidence intervals. The analysis pools across co-ethnicity; that is, mean responses of
subjects assigned to the “co-ethnic, non-cousin” or “non-coethnic, non-cousin” conditions are subtracted from the
mean responses of subjects assigned to the “co-ethnic cousin” or “not-coethnic cousin” conditions.
Treatment effects, in sum
•
Both co-ethnicity and cousinage alliances make evaluations of
the politician more positive—but cousins from a different ethnic
group are just as attractive as non-cousins from voters’ own
ethnic group
•
That is, evaluations of co-ethnic non-cousins and non-coethnic cousins
are statistically indistinguishable
•
Estimated treatment effects are similar for similar questions
(such as, “on a scale of 1 to 7, how would you rate the global
quality of this speech”)?
•
Trustworthiness and credibility appear to play an important
role
•
So may social networks: voters in both the cousin and the coethnic conditions report having more friends and
acquaintances with the politician’s last name
External validity concerns
•
External validity concerns are very central here
• One narrow sense of external validity: is the
experimental study group representative of the
broader population?
• On ethnicity, apparently
• On gender, not at all
• This is a concern: our results are valid for the experimental
•
•
study group but are they for the broader population?
On the other hand, treatment effects are very similar for men
and for women (we also use sampling weights, with caveats,
to construct estimates for the broader population)
But can the experimental results explain the real-world
puzzle?
• The issue of “variance explained”
Can the Experimental Evidence Explain the Observational Data?
Three Important Points
1. Cousinage relations are politically (and not just culturally or
socially) salient
•
•
Treatment effects are much stronger for politically-active subjects
Candidates exploit cousinage relations in campaigns
2. Cousinage relations are widespread
•
•
The probability that a politician and a voter drawn at random are
cousins matches or exceeds the probability that they are co-ethnics
E.g., for a Keita, the probability that a voter drawn at random is a coethnic is about 0.15; the probability that s/he is a cousin is about 0.52
3. Co-ethnic and cousinage ties are negatively associated
•
•
E.g., among eligible subjects who are not ethnically Malinké, an ethnic
Malinké named Keita is most likely to be a cousin, while among
Malinkés, a Keita is most likely to be a non-cousin
Voters prefer co-ethnics; but an unobserved omitted variable
attenuates the observed correlation between co-ethnicity and
candidate preferences
Other results (see paper!)
•
We also test the observable implications for party
strategy
• Parties appear to exploit cousinage networks in placing
•
•
candidates on lists
We use Afrobarometer data and surnames of candidates in
the 2007 parliamentary elections to evaluate this
Note that it is useful to combine observational and
experimental data in this regard – particularly, to link
the experimental results to real-world outcomes and
(partially) address concerns about external validity
Example 2: Combining Field and Natural
Experiments to Strengthen Causal Inference
•
Several recent papers combine field and natural experiments
or merge true experiments at different levels of analysis
• Beaman et al. 2008, Fearon et al. 2009
•
Such approaches can be quite useful for measuring the causal
impact of institutions
•
Here I present research on how electoral quotas shape the
salience of caste in India
•
I use a field experimental design similar to the design in Mali –
but embed the field experiment in a natural experiment, in
which caste quotas for the presidencies of village councils are
“as-if” randomly assigned
The Salience of Ethnic Categories
•
Political leadership and electoral rules may shape the salience
of different forms of ethnic identification
•
In India, presidencies of some village councils are reserved,
via an electoral quota, for presidents from lower-caste groups
• Such quotas may increase the salience of the larger caste
category on which reservation is based, at the expense of the
individual sub-castes that comprise the category
• Yet estimating causal effects is difficult, if reservation is related
to observed or unobserved characteristics of council
constituencies
Measuring the Effect of Reservation:
A Regression-Discontinuity Design
• Reservation of council presidencies rotates across village councils
on the basis of population proportions of the targeted groups
• I exploited an RD design to construct a study group of 160
councils, located in the state of Karnataka, in which reservation is
plausibly assigned as-if at random
• The main advantage: we can attach causal interpretations to postreservation differences across reserved and unreserved councils
• The procedure also produces a study group of council
constituencies in which the population proportion of the targeted
groups varies greatly, which may help with external validity
Measuring Caste-Based Preferences: A Field Experiment
• In the 160 selected villages, I then implemented a field experiment
in which I manipulated the perceived caste relationship between
subjects and a videotaped actor/political candidate (by changing the
surname of the politician)
• Subjects were assigned at random to one of three conditions:
• Subject and politician share the same sub-caste, same larger category
• Subject and politician from different sub-castes but the same larger category
• Subject and politician are from different larger categories
• The identity of the actor and the text of the speech were identical
across conditions (with a few caveats)
• I can then compare subjects’ evaluations of the politician (including
vote preference) across treatments; and I can compare treatment
effects across reserved and unreserved council constituencies
Caste categories in Karnataka
• The structure of caste in Karnataka raises interesting
questions about the salience of ethnic categories
• Two main jatis comprise the Scheduled Castes
• The Holaya and the Madiga are former Untouchable sub-castes (Harijans),
with some history of antagonism and competition
• There are two dominant jatis among the Backward Castes
• The Vokkaliga and Lingayath sub-castes tend to dominate politics at
the local and state level
• So what dimension of caste is most important to voters?
• E.g., Holaya/Madiga or Scheduled Caste?
• Vokkaliga/Lingayath or Backward Caste (anti-SC)?
• And what shapes the relative salience of these categories?
Reservation: The system of rotation
• Reservation for lower-caste politicians of the council presidencies has
been assigned as follows, starting with the 1994 elections:
1) In each taluk (an administrative unit below the district), the number N of presidencies
2)
3)
4)
5)
6)
7)
to be reserved for each group (Scheduled Caste or Scheduled Tribe) is determined
by each group’s population proportion in the taluk as a whole
To allocate reservation to particular panchayats, a bureaucrat lists panchayats in
descending order by the number of council seats reserved each relevant group; the
number of reserved seats is determined by the proportion of each group in the
panchayat population
Then, starting with the Scheduled Caste category, the bureaucrat moves down the
list of panchayats, reserving the first N presidencies
The same is then done for Scheduled Tribes; the remaining Gram Panchayats are
reserved for two groups of Backward Castes (A and B) or left for the General
category
Within a bin (defined by the number of reserved seats), if there are more councils
than presidencies to be reserved, reservation is allocated by lottery
In the next election, the bureaucrat takes up where he or she left off, rotating
reservation to the next N villages on the list, for each respective category
If, in any election, a Gram Panchayat is already reserved for one category (e.g.,
Scheduled Caste) but appears in among the GPs that should be reserved for
andother category (e.g., Scheduled Tribe), the panchayat is skipped and then
reserved for the latter category in the subsequent election
Verifying the assignment procedure
• I obtained reservation data for the entire state of Karnataka for each
presidential term (1994, 2000, 2002, 2005, 2007)
• This allows me to verify that the selection procedure was actually
employed
• Bureaucrats are required by state regulations to hold meetings at the
taluk level, where the identity of reserved councils are announced and
the criteria for allocation are explained
• This should increase the transparency of the process and limit the
potential for lobbying
• Fieldwork confirms that at least some of these meetings were held
Village selection: a regression-discontinuity design
• I mimicked the process of reservation as closely as possible, using
•
•
census data on group proportions (the same data used by the
bureaucrats)
By listing panchayats in descending order of population proportion for
each group, and using reservation data, one can find the threshold
points: that is, the cut-point between panchayats in each category that
were reserved and those that were not
The idea of the regression-discontinuity design is to select councils on
either side of, and nearest to, the threshold. Observed and unobserved
variables should be very nearly balanced—and assignment to
reservation thus may be plausibly “as-if” random near the threshold
• Local independence is bolstered in Karnataka because many panchayats with similar
group proportions will have the same number of seats reserved for members—and
then reservation of the presidency is assigned via a lottery
• One hiccup is that I used the underlying populations proportions (sigh),
•
whereas bureaucrats used the number of members’ seats; though the
latter are based on the underlying proportions, larger panchayats will on
average be higher on the list
However, this should not bias inferences, since councils just above and
below my thresholds should have similar populations, on average
Reservation: as-if randomization checks
Group 1:
Group 2:
Reserved for SC or ST
Difference of Means
(A) - (B)
p-value (two-sided)
(A)
Unreserved or reserved
for OBC
(B)
Mean population
(Standard error)
5684.17
(200.44)
6055.3
(180.60)
-371.13
(269.80)
0.17
Mean SC population
(Standard error)
1119.21
(91.91)
1114.16
(67.84)
5.05
(114.23)
0.96
Mean ST population
(Standard error)
505.52
(56.70)
444.85
(43.86)
60.67
(71.69)
0.40
Mean number of
literates
(Standard error)
3076.63
(111.46)
3315.61
(114.5)
-238.98
(159.79)
0.14
Mean number of
workers
(Standard error)
2860.12
(103.03)
3017.59
(92.41)
-157.47
(138.40)
0.26
Mean male population, mean male population age 0-6, mean number of marginal workers, and other pretreatment covariates are omitted but also pass the covariate balance test. P-value for assignment covariates is
0.97 (SC proportion) and 0.26 (mean ST proportion).
Design of the field experiment
•
I filmed an actor delivering two versions of a political
speech (in Kannada)
•
During recruitment and prior to random assignment,
subjects revealed their jati and several other attributes on a
screening questionnaire
•
Subjects were shown one of the two (identical) speeches
•
In the introduction to the video and in every follow-up
question, field investigators varied the surname of the
candidate, according to the treatment assigned
Experimental Design
Same caste
category
Same
sub-caste
(jati)
N=458
Different
sub-caste
(jati)
N=470
Different caste
category
N=525
Politician’s surname by treatment condition
(Selected sub-castes*)
Condition 1:
Condition 2:
Condition 3:
Subject’s sub-caste
(jati)
Subject’s caste
category
Subject and
politician are from
same jati and caste
category
Subject and
politician are from
different jati, same
caste category
Subject and
politician are from
different jati and
caste category
Madiga
SC
Madiga
Holaya
Gowda
Lingayath
Holaya
SC
Holaya
Madiga
Gowda
Lingayath
Nayaka or other tribe ST
Nayaka
Madiga
Holaya
Gowda
Lingayath
Lingayath
BC
Lingayath
Gowda
Madiga
Holaya
Vokkaliga
BC
Gowda
Lingayath
Madiga
Holaya
Brahmin
Forward
Deshpande
Gowda
Lingayath
Madiga
Holaya
* Omitted subject sub-castes include Lambani (SC), Kumbara (BC), and Bunt (BC)
Stimulus: The political speech
•
There were two versions of the political speechone
“programmatic” and the other “clientelistic with the
version to be shown assigned at random
•
The programmatic speech focused on general needs and
local public goods
•
The clientelistic speech focused on jobs, schemes,
income and caste certificates, and other targeted benefits
• The content of the speech appears to have had relatively
little impact on candidate evaluations
•
In the analysis, I pool across the two versions of the
speech…
Subject recruitment
• A stratified random sample of ten respondents per village:
•
•
•
Four SC residents (ideally, two Holaya and two Madiga)
One ST resident (Nayaka)
Five residents from the general category (including Backward Castes)
• Some limited substitution of jatis was allowed
• Residential segregation in villages eased the sampling
• Twenty teams of two field investigators visited 10 villages (on average)
• Thus, 200 villages, with 2000 participants
• 40 villages were set aside for a pilot study, leaving 160 villages and
1600 subjects (in principle) for this experiment
• In each village, surveys were also taken of the council president, two
council members, and the executive secretary (more later)
Ethnic distribution of experimental population
Caste category
Sub-caste (jati)
N
Percent
Holaya
331
22.87
Madiga
228
15.76
Lambani
23
1.59
Nayaka
133
9.19
Lingayath
267
18.45
Vokkaliga
246
17.00
Bunt
42
2.90
Other Backward Caste
Kumbara
77
5.32
Forward Caste
Brahmin
97
6.70
Scheduled Caste
Scheduled Tribe
Dominant Backward
Caste
Weaknesses of the experimental design
•
As in Mali, estimated treatment effects may not be large, for a
number of reasons
•
•
•
Stimulus is somewhat artificial?
May not prime caste effectively?
Issues with surnames…
•
In the field experiment, we may therefore expect to estimate
lower-bounds on the effects of caste
•
However, the design is likely to give us a good sense of how
reservation shifts the relative salience of caste categories
Figure 1: Average Voting Preferences,
By Treatment Assignment
4.5
4.45
4.4
4.35
4.3
4.25
4.2
4.15
4.1
Citizen and politician have Citizen and politician have Citizen and politician have
same jati, same caste
different jati, same caste
different jati, different
category
category
category
Chart gives average answers to the question, “On a scale of 1 to 7, how much does this speech make you want to vote for (name of
candidate)?” Jati refers to Vokkaliga, Lingayath, Holaya, Madiga, etc. Caste category refers to SC, ST, OBC, and so on.
The relevance of sub-caste
•
The effects of sharing a sub-caste on candidate evaluations are
statistically significant, relative to the other two treatments
•
In the experimental population as a whole, politicians from a
different sub-caste, but the same caste category, are statistically
indistinguishable from politicians from a different caste category
•
This finding holds for sub-groups, in particular, for both Scheduled
Castes and dominant Backward Castes
•
The estimated effect of treatment assignment is about one-quarter
of one standard deviation
•
This is in the neighborhood of, but somewhat smaller than, the
estimated effects of co-ethnicity in an experiment in Mali
Treatment effects, in sum
•
Many variables may help explain the preference for politicians
from the same sub-caste, relative to different caste categories
•
On the other hand, only the benefits variable significantly
distinguishes among sub-castes, within the same caste
category
•
Politicians from another sub-caste but the same category are
significantly preferred to politicians from a different caste
category only on credibility grounds
•
Does reservation of the council presidency shape the relative
salience of different caste relationships?
Figure 2: The Effects of Caste on Voting Preferences,
Reserved and Unreserved Panchayats
4.7
4.6
Reserved
Panchayats
4.5
4.4
Unreserved
Panchayats
4.3
4.2
4.1
4
3.9
3.8
3.7
3.6
Citizen and
politician have
same jati, same
caste category
Citizen and
politician have
different jati, same
caste category
Citizen and
politician have
different jati,
different caste
category
Chart gives average answers to the question, “On a scale of 1 to 7, how much does this speech make you want to vote for (name of
candidate)?” “Reserved panchayat” means, reserved for SC or ST adhyaksha. “Unreserved panchayat” means, reserved for OBC or
General category.
Credibility: The Effects of Reservation
0.62
Reserved
panchayats
0.6
Unreserved
panchayats
0.58
0.56
0.54
0.52
0.5
0.48
Citizen and
politician have
same jati, same
caste category
Citizen and
politician have
different jati, same
caste category
Citizen and
politician have
different jati,
different category
The variable measuring “credibility” combines survey questions about the post-election performance of the politician:
whether he is trustworthy, has good motives for running for office, could face the challenges of office, would do a good job
if elected, and would fight for others and defend his ideals once in office. The variable is scaled to run from 0 to 1.
Benefits: The Effects of Reservation
0.62
0.6
0.58
Reserved
panchayats
0.56
Unreserved
panchayats
0.54
0.52
0.5
0.48
Citizen and
politician have
same jati, same
caste category
Citizen and
politician have
different jati, same
caste category
Citizen and
politician have
different jati,
different category
The variable measuring “benefits” combines answers to the following two survey questions: “If (name of the politician)
were elected, people like you would receive more benefits from the welfare schemes of the government” and “If (name of
the politician) were elected, people like you would have a better chance of getting a job with the government.” The
variable is scaled to run from 0 to 1.
Affection: The Effects of Reservation
0.54
0.53
0.52
Reserved
Panchayats
0.51
Unreserved
Panchayats
0.5
0.49
0.48
0.47
0.46
0.45
0.44
Citizen and
politician have
same jati, same
caste category
Citizen and
politician have
different jati, same
caste category
Citizen and
politician have
different jati,
different category
The variable measuring “affection” combines survey questions about the intelligence, likeability, competence,
and impressiveness of the politician. The variable is scaled to run from 0 to 1.
The causal effects of reservation
(1 = same jati, same caste category; 2 = different jatis, same caste category; 3 = different caste categories)
Vote
preference (12)
Vote
preference (13)
Vote
preference (23)
Affection (1-2)
Affection (1-3)
Affection (2-3)
Credibility (12)
Credibility (13)
Credibility (23)
Estimated
effect,
reserved
panchayats
Estimated
effect,
unreserved
panchayats
(A)
(t-statistic)
(B)
(t-statistic)
0.20
(1.45)
0.23
(1.77)
Estimated
effect,
reserved
panchayats
Estimated
effect,
unreserved
panchayats
(A)
(t-statistic)
(B)
(t-statistic)
Monitoring
(1-2)
0.02
(1.13)
0.01
(0.46)
(A-B)
(t-statistic)
0.01
(0.43)
Monitoring
(1-3)
0.03
(1.30)
0.01
(0.25)
0.02
(0.70)
Monitoring
(2-3)
0.00
(0.14)
-0.01
(-0.23)
0.01
(0.27)
Preferences
(1-2)
Preferences
(1-3)
Preferences
(2-3)
Benefits (1-2)
0.01
(1.12)
0.07
(3.28)
0.05
(2.29)
0.05
(2.17)
0.08
(3.72)
0.01
(0.32)
0.02
(0.85)
0.02
(0.72)
-0.00
(-0.18)
0.02
(1.11)
0.03
(1.49)
0.03
(1.48)
0.01
(0.23)
0.06
(1.94)
0.05
(1.79)
0.03
(0.79)
0.05
(1.63)
0.02
(0.81)
The causal
effect of
reservation
(A-B)
(t-statistic)
-0.02
(-0.11)
0.31
(2.30)
0.12
(0.91)
0.19
(1.03)
0.10
(0.77)
-0.11
(-0.88)
0.21
(1.18)
0.03
(1.50)
0.06
(4.07)
0.04
(2.48)
0.03
(1.82)
0.06
(3.63)
0.03
(1.76)
-0.00
(-0.06)
-0.00
(-0.06)
-0.00
(-0.00)
0.01
(0.62)
0.03
(1.93)
0.02
(1.30)
0.03
(1.15)
0.06
(2.93)
0.04
(1.79)
0.02
(0.88)
0.029
(1.28)
0.01
(0.05)
Benefits (1-3)
Benefits (2-3)
The causal
effect of
reservation
The effects of reservation, in sum
•
Reservation of the council presidency seems to make caste matter
more:
•
•
•
•
•
•
In the sub-group analysis, all (save one) of the statistically significant
effects occur only in reserved panchayats
Reservation shifts the relative importance of caste categories, making
the larger caste grouping relatively more important
Reservation intensifies distinctions between politicians from one’s own larger caste
category and politicians from a different caste category.
It sharpens distinctions between politicians who are from a different sub-caste, but
from the same caste category, and politicians from a different caste category.
Reservation also blurs distinctions between politicians from the same larger group
category (whether or not they come from the subject’s own jati), with one exception:
In general, reservation most strongly shapes measures of affection, as
well as perceptions in-group preferences
Interpreting the results…
•
•
Evidence on the special importance of affective factors
contrasts with many studies.
The “politics of dignity”?
•
Another reason: reservation’s distributive effects may in
fact be more limited than previous evidence suggests
(Dunning and Nilekani 2009)
•
In other work, I try to explain the limited distributive effects;
patterns of party competition at the local level seem
important
•
What about external validity?
External Validity: Comparing Means
in the Study Group and the State of Karnataka
Study Group
State of Karnataka
Mean population
(Standard Deviation)
5869.7
(1912.03)
6132.1
(2287.1)
Mean SC population
(Standard Deviation)
1116.7
(805.7)
1129.7
(760.2)
Mean ST population
(Standard Deviation)
475.2
(506.5)
512.5
(715.8)
Mean number of literates
(Standard Deviation)
3196.1
(1133.4)
3122.7
(1326.7)
Mean number of workers
(Standard Deviation)
2938.9
(979.3)
3005.9
(1092.5)
200
5760
Number of Panchayats
Practical considerations
•
Are studies like these feasible for doctoral dissertations?
•
•
•
Yes!
Researchers spending extended time in the field have a
logistical advantage
•
Conducting interviews oneself or with RAs, over an
extended period of time, reduces costs
•
Great opportunities to merge qualitative fieldwork with field
or natural experimental designs
Other considerations…
Download