I understand Drs. Williams and Sowell’s point, but to compare Harlem and Lower East Side students in the late 40’s and early 50’s does not seem illuminative. Was not the LES a rank slum of non-English-speaking Puerto Rican immigrants at that time?
Here’s a description of the immigrant population in the area in the late 40’s:
“...the area was becoming a destination for thousands of Puerto Ricans in a huge postwar migration. Men found work as janitors, women as sewing machine operators, settling with their extended families into tenements that had previously housed Jewish and Italian immigrants.”
http://www.nytimes.com/2010/08/11/nyregion/11mission.html
There does appear to be differing demographic data for the LES in the years given depending on the source being cited. Could it be that for purposes of say, Census taking or statistical analysis that anyone not listed as black was listed as white? And if this was the case would not this caveat need to be factored in so as not to produce a somewhat skewed conclusion? I can pose the question, however I fear the answers are a bit above my areas of expertise and pay grade.