Data are a subset from an observational, longitudinal, study on adopted children. Is child's intelligence related to intelligence of the biological mother and the intelligence of the adoptive mother?
A data frame with 62 observations on the following 6 variables.
adoptive mother's years of education
biological mother's score on IQ test
IQ of child at age 2
IQ of child at age 4
IQ of child at age 8
IQ of child at age 13
Ramsey, F.L. and Schafer, D.W. (2002). The Statistical Sleuth: A Course in Methods of Data Analysis (2nd ed), Duxbury.
Skodak, M. and Skeels, H.M. (1949). A Final Follow-up Study of One Hundred Adopted Children, Journal of Genetic Psychology 75: 85–125.