Finally, before moving to a more thorough analysis, we note from Figure 2 that pass rates for whites appear to be grouped in two distinct branches, one high and one low. On the suspicion that the branches might correspond to SES levels, we constructed a crude SES partition based on average home values. Figure 3 shows the result of this partition for middle-income performance at the satisfactory level. Most of the scatter is gone. Trends are more evident.
Racial integration raises black performance and lowers white .
Regression supplies the answer. We fit pass rates to a linear model, using black eighth-grade percentage and average neighborhood home value as independent variables. The results are summarized in Table 2.