Hi, everybody. I had a question with regard to caculating a p-value for two differnt samples.  So, I have two categories based on mortality (if mortality rate greater than 30%, coded as 1, otherwise coded as 2). And based on this category, I have a sample size of 15 (N1=15) for Category 1, and a sample size of 18 (N2=18) for Category 2. For each observations or counties, I have a number of people who are poor (based on a certain income level) and the total number of population within that county. The number of people who are poor are used as the numerator and the total number of population are used as the denominator.  I also can calculate the overall mean or average percentage of the poor based on the Category (1 or 2) I have described above.  My question is:   How can I write my SAS code to compare the overall mean or average of Category 1 vs. Category 2?? And is there a way to calculate the Variance or Standard Deviation (SD) for each Category? I would greatly appreciate your help!       ... View more