Meta-analysis of behavioral genetic studies of Piagetian cognitive ability
Apparently, only a few studies have examined this question and they are not easily available. Because we obtained these, it makes sense to share our results. The datafile is on Google Drive. We will fill in more results as we find them.
So far results reveal nothing surprising: MZ correlations are larger than DZ correlations. The h2 using Falconer's formula is about 60%. Total sample ≈ 750 pairs.