Fertility differences between married and cohabiting couples: a switching regression analysis

Little is known about why cohabiting couples have fewer children than married couples. We explore the factors that explain the difference in fertility between these two groups using a switching regression analysis, which enables us to quantify the contribution of different factors through a decomposition of the difference. We find that married couples have more children than cohabiting couples primarily because marriage provides stronger incentives for specialization in household production. Unobserved self-selection plays a less important role.