Differential Fertility as a Determinant of Trends in Public Opinion about Abortion in the United States (WP-14-11)
J. Alex Kevern and Jeremy Freese
Differential fertility is frequently overlooked as a meaningful force in longitudinal public opinion change. The researchers examine the effect of fertility on abortion attitudes, a useful case study due to their strong correlation with family size and high parent-child correlation. They test the hypothesis that the comparatively high fertility of pro-life individuals has led to a more pro-life population using 34 years of General Social Survey data (1977-2010). They find evidence that the abortion attitudes have lagged behind a liberalizing trend of other correlated attitudes, and consistent evidence that differential fertility between pro-life and pro-choice individuals has had a significant effect on this pattern. Future studies should account for differential fertility as a meaningful force of cohort replacement in studies of public opinion where parents and children are likely to share the same attitude.