Software

Statistical Software

• CEM: Coarsened Exact Matching by Stefano M. Iacus, Gary King, Giuseppe Porro. This software implements the CEM algorithm, a method of matching for reducing model dependence and improving causal inferences via an extremely simple but extremely powerful approach. (Website: CEM)
• MatchIt: Nonparametric Preprocessing for Parametric Causal Inference, by Daniel Ho, Kosuke Imai, Gary King, Elizabeth Stuart, implements the suggestions of Ho, Imai, King, and Stuart (2007) for improving parametric statistical models by preprocessing data with nonparametric matching methods. MatchIt implements a wide range of sophisticated matching methods, making it possible to greatly reduce the dependence of causal inferences on hard-to-justify, but commonly made, statistical modeling assumptions. The software also easily fits into existing research practices since, after preprocessing data with MatchIt, researchers can use whatever parametric model they would have used without MatchIt, but produce inferences with substantially more robustness and less sensitivity to modeling assumptions. MatchIt also works seamlessly with Zelig. (Website: MatchIt | Track MatchIt changes.)
• Zelig: Everyone's Statistical Software, by Kosuke Imai, Gary King, and Olivia Lau, is a complete statistical package and framework for statistical inference that can estimate, help interpret, and present the results from, a large range of statistical methods. Zelig, which works within R, and has features from Clarify, Amelia, MatchIt, ReLogit, and many other programs. It adds powerful infrastructure, but retains an easy-to-use command structure. The Zelig manual doesn't assume you know R. (Website: Zelig | Track Zelig changes.)
• JudgeIt II: A Program for Evaluating Electoral Systems and Redistricting Plans by Andrew Gelman, Gary King, and Andrew C. Thomas. A program for analyzing most any feature of district-level legislative elections data, including prediction, evaluating redistricting plans, estimating counterfactual hypotheses (such as what would happen if a term-limitation amendment were imposed). This implements statistical procedures described in a series of journal articles and has been used during redistricting in many states by judges, partisans, governments, private citizens, and many others. The earlier version was winner of the APSA Research Software Award. (JudgeIt II Website | Track JudgeIt changes | Earlier version: Website)
• ReadMe: Software for Automated Content Analysis by Daniel Hopkins, Gary King, Matthew Knowles, and Steven Melendez. This program will read and analyze a large set of text documents and report on the proportion of documents in each of a set of given categories. (ReadMe: Website | Track ReadMe changes)
• Amelia II: A Program for Missing Data by James Honaker, Gary King, and Matthew Blackwell. This program multiply imputes missing data in cross-sectional, time series, and time series cross-sectional data sets. It includes a Windows version (no knowledge of R required), and a version that works with R either from the command line or via a GUI (Website: Amelia II | Track Amelia changes)
• VA: Software for Analyzing Verbal Autopsy Data by Gary King and Ying Lu, implementing methods described in "Verbal Autopsy Methods with Multiple Causes of Death" (Website: VA | Track VA changes)
• YourCast: Time Series Cross-Sectional Forecasting with Your Assumptions implements the methods introduced in Federico Girosi and Gary King's book manuscript on Demographic Forecasting. These methods enable one to run sets of time series regressions, each with possibly different sets of explanatory variables, while still borrowing strength in a variety of sophisticated ways. The methods enable much more information to be included in the model, both through covariates and new more informative ways of constructing Bayesian priors in hierarchical and spatial settings. (Website: YourCast | Track Yourcast changes.)
• WhatIf: Software for Evaluating Counterfactuals by Heather Stoll, Gary King, and Langche Zeng. WhatIf offers easy-to-apply methods to evaluate counterfactuals (causal inferences, predictions, and hypothetical questions) that do not require sensitivity testing over specified classes of models. If an analysis fails the tests offered here, then we know that substantive inferences will be sensitive to at least some modeling choices that are not based on empirical evidence, no matter what method of inference one chooses to use. WhatIf implements the methods in Gary King and Langche Zeng. 2006. The Dangers of Extreme Counterfactuals, Political Analysis, forthcoming, and Gary King and Langche Zeng. 2006 (Abstract: HTML). When Can History Be Our Guide? The Pitfalls of Counterfactual Inference, International Studies Quarterly, forthcoming. (Abstract: HTML | Website: WhatIf | Track WhatIf changes.)
• Anchors and other related software for analyzing survey data with anchoring vignettes. These programs (in R and Stata) implement ideas to reduce interpersonal incomparability in surveys developed in Gary King, Christopher J.L. Murray, Joshua A. Salomon, and Ajay Tandon's Enhancing the Validity and Cross-cultural Comparability of Survey Research. (Software: Anchors, etc. | Website: Anchoring Vignettes | Track Anchors changes)
• ReLogit: Rare Events Logistic Regression by Michael Tomz, Gary King, and Langche Zeng. Both versions implement the suggestions described in Gary King and Langche Zeng's "Logistic Regression for Rare Events Data", "Explaining Rare Events in International Relations" and "Estimating Risk and Rate Levels, Ratios, and Differences in Case-Control Studies ". Options for density case-control sampling designs are, at present, only available in the Gauss version. (Software: Stata Version: 1.1, 10/29/99, Gauss Version: 5/6/04 | ReLogit Listserv: [Un-]Subscribe or Search archives)
• CLARIFY: Software for Interpreting and Presenting Statistical Results by Michael Tomz, Jason Wittenberg, and Gary King; version: 2.1, 1/5/2003. This is a set of easy-to-use Stata macros that implement the techniques described in Gary King, Michael Tomz, and Jason Wittenberg's "Making the Most of Statistical Analyses: Improving Interpretation and Presentation". To install Clarify, type "net from http://gking.harvard.edu/clarify" at the Stata command line. The documentation [ HTML | PDF ] explains how to do this. We also provide a zip archive for users who want to install Clarify on a computer that is not connected to the internet. Winner of the Okidata Best Research Software Award. (All questions, bugs, requests: Clarify Listserv [Un-]Subscribe or Search archives). Also try -ssc install qsim- to install a wrapper, donated by Fred Wolfe, to automate Clarify's simulation of dummy variables.
• EI: A Program for Ecological Inference This program provides easy-to-use methods of running all the statistical procedures, diagnostics, and graphics developed in A Solution to the Ecological Inference Problem: Reconstructing Individual Behavior from Aggregate Data (Princeton University Press, 1997). The program requires Gauss and the Gauss module CML. It can run on any computer system that runs Gauss. (Software: ZIP version: 1.9, 2/8/2003 | What's New: HTML | Documentation: HTML, PDF | All questions, bugs, requests: EI Listserv [Un-]Subscribe or Search archives | Track changes)
• EzI: A(n Easy) Program for Ecological Inference by Kenneth Benoit and Gary King. This is a stand-alone, menu-oriented version of EI (see above) that runs under Windows. It does not require Gauss or any other software to run. EzI does everything EI does and with fewer startup costs but, due to the lack of the Gauss command line, is somewhat less flexible. Winner of the APSA Research Software Award. (Software: EXE for Windows Version: 2.7, 4/14/2003 (See readme.1st, included.) | All questions, bugs, requests: EI Listserv [Un-]Subscribe or Search archives)
• Gauss Procedures. A set of utilities and statistical procedures, for those who program in Gauss. (Guass Links: HTML | Track Gauss changes)
• COUNT: A Program for Estimating Event Count and Duration Regressions. A stand-alone, easy-to-use program for running event count and duration regression models, developed by and/or discussed in a series of journal articles by me. (Event count models have a dependent variable measured as the number of times something happens, such as the number of uncontested seats per state or the number of wars per year. Duration models explain dependent variables measured as the time until some event, such as the number of months a parliamentary cabinet endures.) Winner of the APSA Research Software Award. (The program includes the program and documentation in ASCII and Latex; you may prefer the postscript version.) (Software: Windows self-extracting EXE | Window pre-XP version Version: 8/11/2004. Be sure to install ANSI.SYS before using. This software does not work well with some newer versions of Windows, but you can run most of the same procedures within Zelig and all are still available within the commercial Gauss statistical package)
• Maxlik. A set of Gauss programs and datasets (annotated for pedagogical purposes) to implement many of the maximum likelihood-based models I discuss in Unifying Political Methodology: The Likelihood Theory of Statistical Inference, Ann Arbor: University of Michigan Press, 1998, and use in my class. All datasets are real, not simulated. (Software: DOS EXE | Andrew Martin's Data Sets in Stata: HTML)

Other Software

• Dataverse Network Project, a set of integrated developments in web application software, networking, data citation standards, and statistical methods designed to put some of the universe of data and data sharing practices on firmer ground. Create your own dataverse on your web site, a virtual archive with numerous professional archiving services, all without any local software installation.
• The Harvard Geospatial Library Project