 Hi, I'm Dr. Don and I want to spend a few minutes showing you how to use the Excel Data Analysis Toolpack to run a one sample t-test. In fact we will do this in less than three minutes. Check out the notes for my other videos that should answer your questions on t-test theory, the tale of the test, and how to interpret the results of the t-test. This video is just the mechanics of running the test. Now here we are comparing the obesity in Talladega County in Alabama to the average of the other 66 Alabama County's obesity rate. Now the Excel Data Analysis Toolpack does not have a one sample t-test. We have to use the two sample t-test and to do that we need to fool Excel a little bit into thinking we have two samples. And since we're calculating the mean as part of the two sample t-test, we have to have at least two observations, so I just copied that down so you can calculate the average. I'm going to go to Data, Data Analysis, and we're going to drop down until we find the t-test. There are three of them. We want the last one, the two sample, assuming unequal variances. My other videos will explain why we use that one. I'm going to click OK, and now we've got our dialog box. First thing we want to do is put our variable one range, and I'm going to use the Alabama counties and their obesity rates for the first range. Second range, I'm going to put in the little mini sample for Talladega County. We've got labels in the first row. We're going to leave the hypothesized mean difference blank or zero. We're going to leave the default significance level 0.05, and then we're going to click Output Range, Insertion there, and I'm going to put my output right there and click OK. And there's our results. We have the mean of the other Alabama counties. We've got the mean of that little mini sample for Talladega, and we've got a test statistic and one-tail and two-tail p-values. My other videos will explain to you how to interpret this as well as the tail of the test. Hope to see you there.