- In the Chilean case, it does not appear that sorting between schools produces important biases in estimates of peer-group effects. This is telling, because Chile’s large-scale voucher system places fewer constraints on school choices, either public or private, than most schooling systems.
- The classroom mean of mothers’ education is the most important peer determinant of achievement, though subject to diminishing marginal results.
- There is some evidence of a concave relationship between peer variables and achievement, most prominently in the case of mothers’ education.
- In the sample with imputed siblings and twins the fixed effects coefficients on the mean of mother’s education are consistently positive and larger in magnitude than the same coefficients from full sample regressions.
- The estimates suggested that the mean schooling of mothers exhibited the strongest links to achievement, though with diminishing marginal returns.