Public Discourse 24 February 2015
An important new collection of peer-reviewed scholarly papers entitled No Differences? How Children in Same-Sex Households Fare has just been released by the Witherspoon Institute. The papers included and summarized in the book all study the nexus between children’s well-being and the structure of the families in which they are raised. In particular, the authors focus on the efficacy of families in which the adults are involved in a physically intimate same-sex relationship.
The Problem with Convenience Samples
The first paper included in the volume, by Loren Marks, examines the foundations of the position taken by the American Psychological Association (APA) on what it calls “lesbian and gay parenting.” The 2005 APA monograph setting forth that organization’s position asserts that the question of whether the childrearing efficacy of parents in same-sex relationships is at least the equal of that of heterosexual couples is settled, and that the serious academic literature speaks with a single voice on the matter.
The Regnerus Study
Mark Regnerus’s much-bruited study takes an innovative approach to solving the difficulties of generating a large sample of parents in same-sex relationships. Working with the internet-polling firm Knowledge Networks, now acquired by GfK, Regnerus contacted over 15,000 young and early-middle-aged adults and asked them about their childhoods, including whether at least one of their parents had been involved in a same-sex relationship while they were growing up.
Going Straight to the Source: The Advantages and Limitations of Census Data
Of course, even with the reach of a professional internet-polling firm and a survey of over 15,000 individuals, sampling bias can intrude itself, as people cannot be compelled to respond. Moreover, the relative rarity of parents in same-sex relationships means that even a sample size in the tens of thousands of individuals will yield a relatively small set of parents in same-sex relationships, attenuating statistical power. The only way you could avoid these problems would be to get the Census Bureau to conduct your survey as part of the decennial census, to which individuals are required by law to respond.
Does Family Instability Cause Children of Same-Sex Couples to Fare Worse?
Allen, Pakaluk, and Price then go on to show that Rosenfeld’s finding of no difference hinges on two critical decisions: first, he eliminated geographically mobile children who had changed domicile during the preceding five years, and second, he excluded children who had been adopted. Including either group, even with a control variable for the group mean, expands the sample size and increases the power of the tests.
Differences between Gay and Lesbian-Headed Households
In yet another chapter in the new volume, Douglas Allen continues the quest for a large probability sample by working with a 20-percent sample from the 2006 Canadian Census. By 2006, gay and lesbian marriage was legal throughout Canada, and the census question only identified a child as having gay or lesbian parents if she (or he) responded affirmatively to the question, “Are you the child of a (male/female) same-sex married or common-law couple?” This survey provides a glimpse of what society might look like immediately after the legalization of same-sex marriage.
Family Instability Harms Kids—But are Same-Sex Families Necessarily Less Stable?
The papers in this volume follow a trajectory, from the concerns raised by Loren Marks about small convenience samples, to the large survey conducted by Mark Regnerus, to the gigantic census samples analyzed by Douglas Allen, Catherine Pakaluk, and Joseph Price. A picture emerges: in a cross-section of children raised by parents in same-sex relationships, life outcomes tend to resemble those of children raised by single and divorced parents. So perhaps the mechanism for this process is the instability of the families headed by parents in same-sex relationships?
Appendix: Understanding Social Science Research: Bias and Power
The first question someone not immersed in the empirical social-science literature might ask is, “Why is this so complicated? Aren’t there enough studies already for us to have settled these questions?” Two of the main reasons we still have a lot to learn on this subject have to do with the technical issues of bias and power. These are statistical terms of art with somewhat misleading names.