Professor Monica Costa-Dias, Professor at the University of Bristol, served as the opponent at the defense.

The dissertation, titled Essays in Family and Labour Economics, consists of three self-contained chapters that explore how economic incentives and institutional settings shape key decisions within households and labor markets.

In the first chapter, Lyu studies why couples cohabit before marriage and highlight the role of cohabitation as a learning mechanism. By exploiting a Swedish survivor-pension reform and combining it with a structural model, the chapter shows how cohabitation allows couples to learn about compatibility before committing to marriage.

The second chapter examines the effects of family planning policies in China on fertility, human capital, and demographic change. Using an overlapping-generations framework, the research uncovers a human-capital channel beyond the traditional quantity–quality trade-off and discusses how policy design can balance fertility and human capital outcomes.

In the third chapter, Lyu analyzes how local labor market conditions influence entry into platform-based entrepreneurship. Combining large-scale digital platform data with local employment shocks in the United States, the study finds that individuals entering during weaker labor markets tend to adopt more effective business strategies and achieve stronger performance.

Yifan Lyu’s research lies at the intersection of household and labour economics, with a focus on how policies and incentives influence decisions such as marriage, fertility, and entrepreneurship.

Prior to joining the doctoral program, he obtained a double-degree BSc in Economics and Finance from the University of Southampton and Jiangxi University of Finance and Economics, as well as an MPhil in Economic Research from the University of Cambridge.

Read the full dissertation here

Essays in Family and Labour Economics - Stockholm School of Economics