Do Perceptions of Ballot Secrecy Influence Turnout? Results from a Field Experiment

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Suggested citation: 

Gerber et al. (2013), Replication Materials for ‘Do Perceptions of Ballot Secrecy Influence Turnout? Results from a Field Experiment,’ ISPS Data Archive.


Seth J. Hill, David Doherty, Gregory Huber, Alan S. Gerber, Conor M. Dowling

Research design: 
Data type: 
Administrative, survey
Data source(s): 

Authors; CT voter record; Polimetrix/YouGov

Data source information: 


Field date: 
November 28, 2010
Field Date: 
2010-10-28 - 2010-11-02
Location details: 
Unit of observation: 
Sample size: 
Survey: 3,000; Experiment: 894,791
We removed all individuals who (1) were listed as inactive, (2) lacked a valid current Connecticut mailing address (including failing to pass a National Change of Address [NCOA] filter), or (3) had their mail delivered to a post office box. Similarly, we eliminated any voter who voted by absentee ballot in 2006, 2008, or 2010 because many of these individuals may have already voted at the time the mailing was sent. We also removed any registrants less than 18 years of age or over the age of 85. Finally, we removed records from households with more than five registrants at a single address because these individuals are likely to live in temporary (e.g., school dorms) or group housing where mail would be less likely to be delivered on time or where the registrant is more likely to have moved. From this pool of eligible registrants, if there were multiple eligible registrants from a single household (address), we randomly selected a single registrant.
Randomization procedure: 
We identified our three experimental strata and assigned treatments. Within each stratum, randomization took place within blocks (constant proportions for all blocks within the group, and leftovers [groupings too small to be blocked] were independently randomly assigned with the same target proportions). See the supporting information for complete details.
Six of our seven treatment letters appeared on Secretary of State letterhead (full text of all letters appears in the supporting information): SOS Secrecy 1 (Anonymity), SOS Secrecy 2 (No Intimidation), SOS Secrecy Combined, SOS Short, SOS Control, SOS Civic Duty, and Generic Civic Duty.
Treatment administration: 
Outcome measures: 
Archive date: 
Owner contact: 


Terms of use: 

ISPS Data Archive: Terms of Use

Area of study: 
Data file numbersort ascending Description File format Size File url
D100F13 Metadata (DDI 3.2) .xml 46665 Download file
D100F11 Supplementary Materials Adobe Acrobat .pdf 195584 Download file
D100F10 Data File - survey .csv 92160 Download file
D100F08 Data File - survey dat 92160 Download file
D100F07 Data File - experiment .csv 59752448 Download file
D100F05 Data File - experiment dat 59751424 Download file
D100F04 Program File Stata 13 Do-File 1024 Download file
D100F03 Program File Stata 13 Do-File 16384 Download file
D100F02 Program File Stata 13 Do-File 3072 Download file
D100F01 ReadMe File .txt 2048 Download file