Median Income and Median Family Income
Two surprising values that did not correlate were median income and crime rate. Median income had a relatively strong correlation, with r equal to -.517, so we can say with 90% confidence that there is a negative relationship between cumulative AIDS rate and median income. This can in part be explained by the fact that the major transmission rate is MSM, rather than heterosexual or IDU, because MSM aren't spending their money on drugs and are employed. These are successful men who happen to be gay. However, Gilroy, the town with the lowest median income of $62,135, also has one of the lowest cumulative AIDS rates of 121/100,000. Gilroy is the furthest city south in Santa Clara, so it may be that it doesn't fit with the rest of the County in terms of demographics. Without Gilroy, the correlation of median income to AIDS rate is very strong, with an r value of -.674. So in general, the higher the median income, the lower the AIDS rate. This makes sense because areas with higher median income are going to have a higher general education level, and are therefore likely to know more about the risks of transmission of HIV/AIDS. Below are the graphs of median income versus AIDS rate, the first one with Gilroy, and the second without. Below that is the map of median income in Santa Clara County, and then the graph for median family income. The data for median income and median family income can be found in Table 9.
