Search Results

Title: Casting Doubt on the Causal Link between Intelligence and Age at First Intercourse: A Cross-generational Sibling Comparison Design Using the NLSY
Resulting in 1 citation.
1. Garrison, S. Mason
Rodgers, Joseph Lee
Casting Doubt on the Causal Link between Intelligence and Age at First Intercourse: A Cross-generational Sibling Comparison Design Using the NLSY
Intelligence 59 (November-December 2016): 139-156.
Also: http://www.sciencedirect.com/science/article/pii/S0160289616300162
Cohort(s): Children of the NLSY79, NLSY79, NLSY79 Young Adult
Publisher: Elsevier
Keyword(s): Age at First Intercourse; Armed Forces Qualifications Test (AFQT); Digit Span (also see Memory for Digit Span - WISC); Intelligence; Intergenerational Patterns/Transmission; Peabody Individual Achievement Test (PIAT- Math); Peabody Individual Achievement Test (PIAT- Reading); Peabody Picture Vocabulary Test (PPVT); Siblings

In this study, we use an intergenerational sibling comparison design to investigate the causal link between intelligence and AFI, using the National Longitudinal Survey of Youth 1979 and the NLSY-Children/Young Adult data. We measured maternal IQ using the AFQT, child IQ using PPVT, PIAT, and Digit Span, and AFI, using respondent self-report. Our analytic method used Kenny's (2001) reciprocal standard dyad model. This model supported analyses treating the data as only between-family data (as in most past studies), and also allowed us to include both between- and within-family comparisons. These analyses included two forms, first a comparison of offspring of mothers in relation to maternal IQ, then a comparison of offspring themselves in relation to offspring IQ.

When we evaluated the relationship between maternal/child intelligence and AFI, using a between-family design, we replicated earlier results; smart teens do appear to delay sex. In the within-family analyses, the relationship between intelligence and AFI vanishes for both maternal intelligence and child intelligence. The finding is robust across gender and age. These results suggest that the cause of the intelligence-AFI link is not intelligence per se, but rather differences between families (parental education, SES, etc.) that correlate with family-level (but not individual-level) intelligence.

Bibliography Citation
Garrison, S. Mason and Joseph Lee Rodgers. "Casting Doubt on the Causal Link between Intelligence and Age at First Intercourse: A Cross-generational Sibling Comparison Design Using the NLSY." Intelligence 59 (November-December 2016): 139-156.