Methods & Data

Specifying and interpreting basic interactions in Stata.
1. Slides from workshop at University of Kentucky.
2. Data for examples in the slides.
3. Related information on Brambor, Clark, and Golder's webpage.
4. More related information on Branton's webpage.

DURSEL: a Stata utility to estimate duration models with selection.
1. Version: DURSEL 2.0 - updated July 03, 2007.
2. Installation: To install, download the zip file or open Stata and type:
   net from http://myweb.uiowa.edu/fboehmke/stata/dursel
3. Sample data for running DURSEL (data used in the Stata help file).

sudcd: a Stata utility for estimating seemingly unrelated discrete-choice duration models.
1. Version: sudcd 1.1 - released March 09, 2008.
2. Installation: To install, open Stata and type:
   net from http://myweb.uiowa.edu/fboehmke/stata/sudcd

precalc: a Stata utility for calculating the proportional reduction in error for a binary model.
1. Version: precalc 1.0 - updated March 13, 2006.
2. Installation: To install, open Stata and type:
   net from http://myweb.uiowa.edu/fboehmke/stata/precalc

grinter: a Stata utility for graphing the marginal effect of an interacted variable in regression models.
1. Version: grinter 1.6 - updated April 29, 2008.
2. Installation: To install, open Stata and type:
   net from http://myweb.uiowa.edu/fboehmke/stata/grinter

Boehmke, Frederick J. 2006. "The Influence of Unobserved Factors on Position Timing and Content in the NAFTA Vote." Political Analysis 14 (4): 421-438.

1. Access to the article and supplemental material.
2. Data and replication files (locally hosted - same as on PA web site).
3. Data and replication files (updated to utilize sudcd Stata utility for estimation; generates identical results).
4. To install sudcd, a Stata utility to estimate seemingly unrelated discrete-choice duration models, see Stata Utilities section.

Boehmke, Frederick J. Daniel S. Morey and Megan Shannon. 2006. "Selection Bias and Continuous-Time Duration Models: Consequences and a Proposed Solution." American Journal of Political Science 50 (1): 192-207.

1. Final version of the paper.
2. Data, replication files, and Monte Carlo code (updated with Monte Carlo on April 18, 2007).
3. To install DURSEL, a Stata utility to estimate duration models with selection, see Stata Utilities section.

Boehmke, Frederick J. 2005. "Sources of Variation in the Frequency of Statewide Initiatives: The Role of Interest Group Populations." Political Research Quarterly 58 (4): 575-585.

1. Published version of the paper.
2. Data and replication files. (Data on the frequency of statewide initiatives, 1976-2000).

Boehmke, Frederick J. and Richard Witmer 2004. "Disentangling Diffusion: The Effects of Social Learning and Economic Competition on State Policy Innovation and Expansion." Political Research Quarterly 57 (1): 39-51.

1. Published version of the paper.
2. Data and replication files. (Data on state and Indian nation gaming compacts).

Boehmke, Frederick J. 2003. "Using Auxiliary Data to Estimate Selection Bias Models, With an Application to Interest Group Use of the Direct Initiative Process." Political Analysis: Volume 11 (Summer 2003): 234-254.

1. Access to the article and its web appendix.
2. Sample Monte Carlo file.
3. Stata 8 dataset. (Data from survey on interest group use of the initiative process).