 Hi, this is Dr. Don. I have a problem out of Chapter 2. This is problem 2.4.57. You're given some raw data from a sample and you're asked to find some descriptive statistics. I want to show you how to do it using Excel. I have another video that shows how to do this using StatCrunch. First thing you need to do is find a little rectangle there that says click to copy table. I'm going to click on that and then I'm going to find open in Excel. I'm going to click on open in Excel and then you'll see that depending upon your browser it will save a copy of that Excel spreadsheet with the data to your local computer. Okay, I've opened that file I downloaded and it'll come up. It'll require you to say enable editing, which I'll do, just click on that and it will enable me to start working on the data. Here's my data in the column A. We're asked to come up with the range, the variance and the standard deviation. The quickest way to do that in Excel is to use the data, data analysis, bring up this dialog, find descriptive statistics, click OK, and then you need to identify your data, clear out anything that's in there, erase it. I'm going to go over here and highlight my data. If you have data that has a label and you include that label in your range, click that. My output range, I'm going to move this out of the way a bit. I'm going to click in there to delete that and then I'm going to put this starting here in this cell C1. You want to double check to make sure you have descriptive statistics clicked so that you can get your descriptive, I'm sorry, summary statistics picked so you can get your descriptive statistics and click OK. You get a lot of information. I'm going to double click on that to expand it so you can see that a little bit better. Here we have our descriptive statistics, mean, standard error, median mode. There's a standard deviation they wanted and the sample variance as well as the range, min, max, sum and count. That's a quick way to get your descriptive statistics. I want to look over here for a second, though, and this student tried to come up with the answers using Excel and let me bring up his spreadsheet for a second. It appears that this student copied the data manually or entered it manually into his spreadsheet instead of using the copy table technique, which is faster and cut down errors. He manually got the sum using the sum function, which is OK. He got the mean using the average function, which is OK. He got the range by taking the max and there the max function, the min function and subtracting those two to get the range, which was a correct answer. His first problem, though, came from the variance. He used the Excel function variance.p. The .p stands for population and here we're told that we have a sample. So if you use the .p function, you will get the wrong answer, which he did. What you need to use when you have a sample, I'm going to start typing here, and you'll see we've got an option, s, .s, estimates based on sample. So I'm going to double click that to enter it, and then select my range, enter, and we get the correct answer, 6.18. So be aware of that, and that is the same thing that's true for standard deviation. This student used the old function standard stdev, which is a default for standard of the sample. In the same way with the variance, if you start typing in your Excel, and you'll see that there's a standard p for population and a standard s for sample. So make sure in the newer versions of Excel that you use the correct function, either the sample or the population to get your descriptive statistics. But again, I would recommend that if you're using Excel on a PC or a recent version of Excel on a Mac, use the data analytics tool to get these descriptors much, much faster.