Wooldridge Source: Altonji, J.G., T.E. Elder, and C.R. Taber (2005), <U+201C>An Evaluation of Instrumental Variable Strategies for Estimating the Effects of Catholic Schooling,<U+201D> Journal of Human Resources 40, 791-821. Professor Elder kindly provided a subset of the data, with some variables stripped away for confidentiality reasons. Data loads lazily.