[Excerpt] Holzer's paper has a number of attributes that I find very appealing. It focuses on an important topic and uses two different data bases to test the robustness of its findings. It uses alternative specifications of the variable of interest (reservation wages), examines the sensitivity of the results to alternative sets of control variables, uses a variety of statistical methods to confront a number of statistical issues, and honestly reports cases in which any of the above leads to differences in results. Finally, the paper does not claim more than the evidence warrants—a feature not present in enough academic research papers. My comments below should be taken with this overall evaluation in mind. I first raise some methodological issues and then turn to future research questions posed by the paper.