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Information Spillovers: Another Look at Experimental Estimates of Legislator Responsiveness

  • Alexander Coppock (a1)

A field experiment carried out by Butler and Nickerson (Butler, D. M., and Nickerson, D. W. (2011). Can learning constituency opinion affect how legislators vote? Results from a field experiment. Quarterly Journal of Political Science 6, 55–83) shows that New Mexico legislators changed their voting decisions upon receiving reports of their constituents’ preferences. The analysis of the experiment did not account for the possibility that legislators may share information, potentially resulting in spillover effects. Working within the analytic framework proposed by Bowers et al. (2013), I find evidence of spillovers, and present estimates of direct and indirect treatment effects. The total causal effect of the experimental intervention appears to be twice as large as reported originally.

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Aronow P. M. 2013. “Comment: Reasoning About Interference Between Units”. Unpublished Mm, 1–7.
Aronow P. M., and Samii C. 2013. Estimating Average Causal Effects Under Interference Between Units. Unpublished manuscript, Yale University, New Haven, CT.
Berger R. L., and Boos D. D. 1994. P Values Maximized over a Confidence Set for the Nuisance Parameter. Journal of the American Statistical Association 89 (427): 1012–16.
Bowers J., Fredrickson M. M., and Panagopoulos C. 2013. Reasoning About Interference Between Units: A General Framework. Political Analysis 21 (1): 97124.
Butler D. M., and Nickerson D. W. 2011. Can Learning Constituency Opinion Affect how Legislators Vote? Results from a Field Experiment. Quarterly Journal of Political Science 6: 5583.
Cox D. R. 1958. Planning of Experiments. New York: Wiley.
Fisher R. A. 1935. The Design of Experiments. Edinburgh: Oliver and Boyd.
Hodges J. L. Jr., and Lehmann E. L. 1963. Estimates of Location Based on Rank Tests. The Annals of Mathematical Statistics 34 (2): 598611.
Hong G., and Raudenbush S. W. 2006. Evaluating Kindergarten Retention Policy. Journal of the American Statistical Association 101 (475): 901–10.
Hudgens M. G., and Halloran M. E. 2008. Toward Causal Inference with Interference. Journal of the American Statistical Association 103 (482): 832–42.
Jacobs L. R., Lawrence E. D., Shapiro R. Y., and Smith S. S. 1998. Congressional Leadership of Public Opinion. Political Science Quarterly 113 (1): 2141.
Kingdon J. W. 1989. Congressman’s Voting Decisions. Ann Arbor, MI: University of Michigan Press.
Manski C. F. 2013. Identification of Treatment Response with Social Interactions. The Econometrics Journal 16 (1): S1–23.
Nolen T. L., and Hudgens M. G. 2011. Randomization-Based Inference Within Principal Strata. Journal of the American Statistical Association 106 (494): 581–93.
Poole K. 2007. Changing Minds? Not in Congress! Public Choice 131 (3/4): 435–51.
Poole K., Lewis J., Lo J., and Carroll R. 2011. Scaling Roll Call Votes with Wnominate in R. Journal of Statistical Software 42 (14): 121.
Rosenbaum P. R. 2002. Observational Studies (2nd ed). New York: Springer-Verlag.
Rosenbaum P. R. 2007. Interference Between Units in Randomized Experiments. Journal of the American Statistical Association 102 (477): 191200.
Rubin D. B. 1980. Randomization Analysis of Experimental Data: The Fisher Randomization Test Comment. Journal of the American Statistical Association 75 (371): 591–93.
Sobel M. E. 2006. What Do Randomized Studies of Housing Mobility Demonstrate? Journal of the American Statistical Association 101 (476): 13981407.
Vote Smart. 2008. Vote Smart of 2008 New Mexico Key Votes. Retrieved from on November 1, 2012.
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Journal of Experimental Political Science
  • ISSN: 2052-2630
  • EISSN: 2052-2649
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