Format
This data frame consists of 140 children (the rows). Column 1 is the subject number and column
2 is the sex (0=MALE and 1=FEMALE). Columns 3 through 26 give the 8 responses at each of the ages 4, 5, and 7.
Columns 27 through 56 give the 10 responses at each of the ages 11, 14, and 18. A value of 99 denotes missing data.Source
Thomas, H. and Dahlin, M. P. (2005) Individual Development and Latent Groups: Analytical Tools for Interpreting Heterogeneity,
Developmental Review 25(2), 133--154.