Where it matters to be the only one: new comparative evidence on the performance of only-children from PISA 2000 and ISEAD
Seongsoo Choi (Sungkyunkwan University, Seoul, Republic of Korea)
Despite the increasing concern about only-children in low-fertility societies, scientific evidence on how they perform developmentally relative to children with siblings has been far from conclusive. We attribute this inconsistency to the lack of comparative approach, highlighting the importance of country's family size context. Using data from the Program for International Student Assessment (PISA) 2000 on 15-year old students and International Sibsize and Educational Attainment Database (ISEAD) on adult children, we examine how family socioeconomic status and various cognitive and noncognitive outcomes of only-children vary across countries. We find that only-children's family background and educational performance relative to children with siblings are consistently better across a range of cognitive and non-cognitive outcomes at age 15 in countries where small families are more common. Their relatively better performance in cognitive outcomes (e.g., reading and math) is largely explained by their family origin advantage, while the family origin difference explains only small part of their better performance in interpersonal outcomes. Our evidence further suggests that such systematic cross-national differences in the premium of being an only-child at age 15 is extended to educational attainment in the adulthood. Lastly, the importance of country's family size context is attenuated at most modestly by the indicators of various public policies. Our study illuminates an important route of intergenerational transmission of family (dis)advantages through changing family size in the era of low fertility.