China

This study examines how rising sex ratios in China affect labor supply among the urban elderly, finding that higher sex ratios increase employment among elderly fathers of sons compared to fathers of daughters. The increase in labor supply is driven by higher marriage costs and reduced old-age support, and high sex ratios are also associated with reduced consumption and well-being among fathers of sons.

Using Chinese provincial panel data (2011–2020), this study finds that income inequality significantly reduces fertility rates and lowers educational expenditures, though the interaction between inequality and education spending can positively affect fertility, especially when income gaps are relatively small. Using after-school tutoring expenditure as an instrumental variable to address endogeneity, the authors also find that the 2016 two-child policy had limited impact, and recommend that the government reduce families' educational financial burden to help raise fertility.

Using China's One-Child Policy in a regression discontinuity design, the study finds that only children are more risk-averse, less trusting, and less socially engaged than those with siblings, which reduces their participation in FinTech services but not traditional finance. These effects are large, persist beyond economic and digital-access differences, are stronger among less educated individuals and in regions with weaker investor protection, and only children pull back more from digital platforms after scandals, underscoring trust as a key mechanism. The findings suggest that global fertility decline could psychologically constrain the digital transformation of finance.

This study uses China's 2015 Universal Broadband and Telecommunication Services pilot program as a quasi-experiment, combined with 2013–2021 China Household Finance Survey data and difference-in-differences estimation, to examine broadband's effect on rural-urban migration. It finds that improved internet access raised rural-urban migration by 3.2–3.4 percentage points (a 17.5–18.6% increase over the 18.3% baseline rate), with stronger effects in villages with fewer initial migrants, closer to county centers, and better roads, and among women, younger, more educated, and higher-income individuals. The authors conclude that broadband acts as "digital routes" enabling out-migration—via greater access to economic information—rather than "digital roots" that keep people in rural areas.