T-scores are standardized scores on each dimension for each type. A score of 50 represents the mean. A difference of 10 from the mean indicates a difference of one standard deviation. Thus, a score of 60 is one standard deviation above the mean, while a score of 30 is two standard deviations below the mean.

Click here and here for descriptions of the generation of neighborhood-type maps of the Chicago area in 2000 and 1990 that make use of T-scores.