Wolff has recently reinterpreted the data of Lee to indicate that Black migration from the south to Philadelphia had been selective in an IQ-relevant manner. However, Wolff's deduction from Lee's data is shown to depend entirely upon an assumption about cumulative IQ deficit in southern Black children. (Author/CTM)

Kamin has contended that arguments presented in Wolff are too weak to justify selective migration. Although Kamin's critique points up the need for closer scrutiny of the cumulative-deficit phenomenon, it fails to refute Wolff's conclusion that selective migration is partly responsible for the North-South Black IQ differential. (Author/CTM)