Researcher in microeconomics and macroeconomics, with notable contributions in poverty, inequality, and economic growth. Integrates sociological ideas into economic analysis and pioneers statistical mechanics techniques in modeling socioeconomic behavior. Develops identification analyses for empirical analogs of models and techniques for policy evaluation. Critic of social capital concept and challenges the use of agent-based modeling and complexity theory in studying socioeconomic phenomena. Writes on fairness and justice, advocating for "associational redistribution" policies.