Evaluating expert judgments (With Gary Marks), European Journal of Political Research 46(3). Journal
Although expert surveys have gained a prominent place in comparative studies of party positions on issues, their validity has been called into question. In this article, some of the validity concerns are evaluated in the context of the authors' own expert survey on national party positions vis-à-vis European integration. One goal of the article is to demonstrate that this expert survey produces valid measures of party positions. An equally important goal, however, is to suggest some methods that can help in assessing the quality of expert survey data. These methods, which are rooted in psychometric theory, are applicable in a variety of contexts and are easily implemented.
Measuring Political Deliberation: A Discourse Quality Index (With A. Bächtiger, M. Spörndli and J. Steiner), Comparative European Politics 1(1). Journal
In this paper, we develop a discourse quality index (DQI) that serves as a quantitative measure of discourse in deliberation. The DQI is rooted in Habermas' discourse ethics and provides an accurate representation of the most important principles underlying deliberation. At the same time, the DQI can be shown to be a reliable measurement instrument due to its focus on observable behavior and its detailed coding instructions. We illustrate the DQI for a parliamentary debate in the British House of Commons. We show that the DQI yields reliable data and we discuss how these data could be used in subsequent analysis. We conclude by discussing some limitations of the DQI and by identifying some areas in which it could prove useful.
Modeling Multilevel Data Structures (With Bradford S. Jones), American Journal of Political Science 46(1). Journal
Multilevel data are structures that consist of multiple units of analysis, one nested within the other. Such data are becoming quite common in political science and provide numerous opportunities for theory testing and development. Unfortunately, this type of data typically generates a number of statistical problems, of which clustering is particularly important. To exploit the opportunities offered by multilevel data, and to solve the statistical problems inherent in them, special statistical techniques are required. In this article, we focus on a technique that has become popular in educational statistics and sociology-multilevel analysis. In multilevel analysis, researchers build models that capture the layered structure of multilevel data, and determine how layers interact and impact a dependent variable of interest. Our objective in this article is to introduce the logic and statistical theory behind multilevel models, to illustrate how such models can be applied fruitfully in political science, and to call attention to some of the pitfalls in multilevel analysis.
The Responsive Voter: Campaign Information and the Dynamics of Candidate Evaluation (With Milton Lodge and Shawn Brau), American Political Science Review 89(2). Journal
We find strong support for an on-line model of the candidate evaluation process that in contrast to memory-based models shows that citizens are responsive to campaign information, adjusting their overall evaluation of the candidates in response to their immediate assessment of campaign messages and events. Over time people forget most of the campaign information they are exposed to but are nonetheless able to later recollect their summary affective evaluation of candidates which they then use to inform their preferences and vote choice. These findings have substantive, methodological, and normative implications for the study of electoral behavior. Substantively, we show how campaign information affects voting behavior. Methodologically, we demonstrate the need to measure directly what campaign information people actually attend to over the course of a campaign and show that after controling for the individual's on-line assessment of campaign messages, National Election Study-type recall measures prove to be spurious as explanatory variables. Finally, we draw normative implications for democratic theory of on-line processing, concluding that citizens appear to be far more responsive to campaign messages than conventional recall models suggest.