The identical twin data, as I understand it, was based on a sample that had relatively little socioeconomic and cultural variation. The parents were similar. Moreover the fact that they volunteered almost certainly meant that there was less variation in their interactions and parenting style than would be foukknd with a more hetergeneous population. When the variance due to social class and parenting styles are small then other variables would account for more of the variance. If a wider sample were used and the problems of volunteerism worked out, I suspect that parent's interaction with children would account for more of the variance in children's behavior. _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com
