Welcome
Welcome! This is the professional home of Stephen Haptonstahl, Assistant Professor of Political Science at the University of California, Davis.
Check out my research, the courses I teach, and software I have written.
Competing Solutions to the Principal-Agent Model
We develop two strategic statistical models of the principal-agent game and discuss how to use them to distinguish among substantive explanations for deviations from subgame-perfection. [Working paper]
Why So Serious? Explaining the Ultimatum Game
Applies a strategic statistical model to the gathered lab data to explain overly generous offers and mysterious rejections. [Working paper]
Bargaining Under Uncertainty: a Strategic Statistical Model of the Ultimatum Game
Develops a strategic statistical model of the ultimatum game and presents experimental evidence as to the nature of uncertainty in these games. Presented: PolMeth 2008, APSA 2008, SPSA 2009. [Under review]
Looking Back: an Ordered Network Model of Legal Precedent
Network analysis is flourishing, but theories explaining why networks take the form they do are still in the early stages of development. I am developing a network game to explain how justices choose cases to cite, where utility for opinion authors takes the form of a new empirical measure of node importance. Presented: 2009 Midwest. [Working paper]
Editing R files with nano: nanorc
Sometimes I edit R files in a shell using the great, simple text file editor GNU nano. If you do, you will want to add syntax highlighting support for R to nano. This is easy: add a few lines to your ~/.nanorc file and nano will do the rest.
Here are the lines I use:
R package: diPlot
Tools to plot descriptive statistics, posterior distributions, and more. Includes linePlotModels, descripBarplot, and other functions I've found useful.
Non-ignorable Abstentions in Roll-Call Data Analysis
The strategic character of abstentions makes the assumption of ignorability difficult to meet in practice. We discuss different abstention-generating mechanisms to understand the conditions under which they may be deemed ignorable, and extend the MCMC IRT model so as to incorporate information from abstention patterns into inferences about legislators' ideal points. With Guillermo Rosas and Yael Shomer. [In progress]
The Dynamics Of Deliberation And Coordination: An Agent-Based Approach
In collaboration with Randall Calvert. We develop a model of political communication prior to the play of a coordination game and use it to examine the process by which political messages acquire meaning. Presented: Midwest 2007. [Working paper]
Elicited Priors for National Security Research
In collaboration with Jeff Gill, John Freeman, and Aaron Rapport. We are developing a browser-based software system, Elicit, for eliciting structured information about social networks for updating Bayesian models of connectivity. [In progress]