Committee on National Statistics, National Research Council ; Citro, Constance Forbes ; Moffit, Robert A. ; Panel on Data and Methods for Measuring the Effects of Changes in Social Welfare Programs, Michele Ver Ploeg, Robert A. Moffitt, and Constance F. Citro ; Ver Ploeg, Michele ; Citro, Constance F ; Constance F. Citro ; Michele Ver Ploeg ; Moffitt, Robert A. ; Robert A. Moffitt ; Commission on Behavioral and Social Sciences and Education ; Committee on National Statistics ; Division of Behavioral and Social Sciences and Education ; Panel on Data and Methods for Measuring the Effects of Changes in Social Welfare Programs ; Ploeg, Michele Ver ; Panel on Data and Methods for Measuring the Effects of Changes in Social Welfare Programs (U.S.)