The SAGE Handbook of Research Methods in Political Science and International Relations offers a comprehensive overview of research processes in social science - from the ideation and design of research projects, through the construction of theoretical arguments, to conceptualization, measurement, and data collection, and quantitative and qualitative empirical analysis - exposited through 65 major new contributions from leading international methodologists. Each chapter surveys, builds upon, and extends the modern state of the art in its area. Following through its six-part organization, undergraduate and graduate students, researchers and practicing academics will be guided through the design, methods, and analysis of issues in Political Science and International Relations: Part One: Formulating Good Research Questions and Designing Good Research Projects; Part Two: Methods of Theoretical Argumentation; Part Three: Conceptualization and Measurement; Part Four: Large-Scale Data Collection and Representation Methods; Part Five: Quantitative-Empirical Methods; Part Six: Qualitative and Mixed Methods.
The use of pooled time series cross section (PTSCS) data has become ubiquitous in observational analyses across the social sciences. Even the identification revolution that swept through empirical social science in the last two decades finds some merit in using data that combines observations across units and over time, because it allows identification through differences-in-differences approaches exploiting within unit variation. In Mostly Harmless Econometrics (Angrist and Pischke, 2009) – which has obtained cult-like status in applied empirical economics – the authors recommend the use of diff-in-diff or unit fixed effects approaches to identification, requiring pooled data, if an experiment is infeasible, a meaningful discontinuity, or exogenous variation in the form of an instrument cannot be found.