Chapter 1 investigates the relationship between family size and intergenerational inequality. I construct a fuzzy regression discontinuity design by the exogenous variation in fertility caused by the one-child policy. My findings present the one-child policy only reduces urban fertility. The empirical findings also suggest a negative correlation between family size and intergenerational inequality, but no causal effect exists. The role of siblings in sharing risks, son preference, more accessible student loans and relaxed budget constraints are plausible explanations for no causal effect.Chapter 2 introduces firm-specific returns to experience and tenure into a standard two-way fixed effects model and provide new evidence on heterogeneity of returns to experience and tenure across firms using administrative matched employer-employee data from Brazil from 1999 to 2014. We find that 1) assuming that employer-employee match quality is determined by firm-specific wage premia and firm-specific returns to experience and seniority, returns to tenure are not strongly related to firm wage premia (i.e. firm FEs), 2) returns to experience are strongly negatively correlated with firm wage premia, 3) the relationship between firm wage premium and return to experience is stronger for “blue collar” firms.Chapter 3 employs the demographic shocks in the late Qing dynasty as the instrumental variable to analyze the causal link between early industrialization and marriage patterns using a unique historical dataset. Our findings present a significantly negative relationship between early industrialization and fertility but no significant causal link between early industrialization and marriage age. While this indicates industrialization could reduce fertility, it may also suggest parents are more likely to use intra-marital birth control methods to limit fertility rather than delaying marriage age in traditional Chinese society. Finally, the opportunity cost of childcare for women and the quality-quantity trade-off are two main channels linking early industrialization to fewer children.