Peers and Possible Partners: Exploring the Origins of Population Long-term Equilibria

Introduction

Population dynamics are a crucial driver of the prosperity of nations. Nowadays, fertility is too high in less developed countries, impeding their escape from poverty, and too low in more developed countries, threatening their very existence. Another concern is the global rise of childlessness among men, which correlates with mental health issues and social unrest.

Objectives of P3OPLE

P3OPLE contributes to addressing these challenges by studying how social and market interactions shape the dynamics and distribution of fertility. I will introduce and test the empirical relevance of two novel concepts:

1. High/Low Fertility Traps
2. Involuntary Male Childlessness

High/Low Fertility Traps

The first concept revolves around peer effects in fertility preferences and revisits an unsettled debate: why are some communities trapped in sub-optimally high or low fertility equilibria? I will discuss how information and coordination failures, conformism and competition, as well as immigration, can prevent or facilitate fertility change.

Involuntary Male Childlessness

The second concept deals with general equilibrium effects on the matching market and raises an unexplored question: can a man be involuntarily childless due to a relative scarcity of female partners on the matching market? I will quantify the importance of unbalanced sex ratios, polygamy, and serial monogamy as drivers of reproductive inequalities.

Interdisciplinary Approach

Both concepts cross the boundaries of disciplines by integrating insights from demography, sociology, and evolutionary biology into economic frameworks.

Methodology

The methodology will combine economic theory and cutting-edge empirical analysis, including experimental, observational, and structural methods, to provide quantitative evidence on novel causal links.

Data Collection

Finally, I will build databases with information on male fertility and subjective determinants of fertility never consolidated or collected at such a large scale. They will allow researchers to answer open questions and explore novel ideas inspired by hitherto undocumented patterns.