Title: Pension Generosity and Fertility: Resolving a Theoretical Paradox with a New Index

Speaker: Wang Leran, Assistant Professor and Master's Supervisor of the School of Public Administration, East China Normal University.

Research fields: Focus on low fertility and aging, fertility intention, unemployment, labor behavior, and pension fields;

Academic achievements: Published research results in renowned economic journals such as Journal of the Economics of Ageing and Economics Letters;

Presided projects: Undertakes multiple provincial and ministerial-level scientific research projects such as the Shanghai Philosophy and Social Sciences Planning Project, the Shanghai Pujiang Talent Program Project, and the National Intelligent Pension Base Project.

Abstract: Traditional theory holds that the expansion of the public pension system will crowd out the demand for "children supporting the elderly", thereby reducing fertility; however, Japan's pension reform from 2004 to 2017 (increasing contribution standards and simultaneously raising pension benefits) was accompanied by an increase in fertility, forming a theoretical paradox.

By constructing an overlapping generations model incorporating "endogenous labor supply" and "efficiency wage hypothesis", this study compares "altruistic" and "self-interested" fertility motives to analyze the causes of the paradox:

    Core mechanism: The net effect of      pension expansion depends on the balance between the "positive income      effect" and the "negative tax effect", and the study      constructs a new "Pension Generosity Index (PGI)" to quantify      this balance;

    Motivation      characteristics:      Fertility motivation gradually shifts from "self-interested" to      "altruistic", and different motives have differentiated      responses to different pillars of the pension system;

    Research value: This conclusion      has been verified in multiple economic contexts. The PGI framework not      only resolves the paradox between Japan's pension reform and fertility but      also provides a universal dynamic analysis tool for evaluating the      demographic and labor market impacts of social security reforms in various      countries.

Date & time: 24 December 2025, 10:00 - 12:00

Venue: B321, Block B, Zhixin Building, Central Campus, Shandong University