Find and interpret a 99% confidence interval for the difference in mean housing price between New Jersey and Pennsylvania.

Refer to the dataset Homes For Sale, which has data on houses available for sale in three Mid-Atlantic states (NY, NJ, and PA) as well as California (CA). Table 6.17 has summary statistics for each of the four states, with prices given in thousands of dollars. (Since n = 30, we ask you to use the t-distribution here despite the fact that the data are quite skewed. In practice, we might have enough concern about the skewness to choose to use bootstrap methods instead.)

Table 6.17

Mean Std. Dev. State New York New Jersey Pennsylvania California 30 565.6 697.6 30 388.5 224.7 179.3 1112.3 30 249.6 715.1 30