Does ignorance or familiarity breed racism against blacks?
To answer this question, I correlated how cool a white person feels towards blacks with the percent of the population in their region that is black (General Social Survey data). The correlation across nine census divisions is .48--a strongly positive correlation.
In other words, whites who live in areas with more blacks--an indication that one has had more actual experience with blacks--tend to feel cooler toward them.
The data suggests that familiarity breeds contempt, not affection.