 Statistics and Excel. Bell Curve. Test score example part number one. Get ready, taking a deep breath, holding it in for 10 seconds, looking forward to a smooth soothing Excel. Here we are in Excel. If you don't have access to this workbook, that's okay because we'll basically build this from a blank worksheet. But if you do have access, there's three tabs down below. Example, practice, blank. Example, in essence, answer key, practice tab, having pre-formatted cells so you can get to the heart of the practice problem. Blank tab, blank worksheet so we can practice formatting the cells within Excel as we work through the practice problem. Let's go to the example tab to get an idea of where we will be going. Working with the bell curve or normal distribution starting out with an example familiar to both students and instructors, that of course being grades. We'll actually use a random generator tool to create our data. Great tool to be familiar with as you practice with a bell curve, for example. Doing some calculations will create a histogram seeing if the characteristics of our data might conform to those of a bell curve. If so, which of course we hope it will then, we will then plot the actual information to create a bell curve and then create a bell curve and we'll get a little fancy with the characteristics of the bell curve in a following presentation. All right, let's go into the blank tab to get down to business. I'm going to start by formatting the entire worksheet as we always do, selecting the triangle up top, right clicking on the selected area, formatting the cells. I usually go to currency and then negative numbers bracketed and read with no dollar sign and removing the decimals. I'm going to say, okay, I'm going to put some standard data here that I'm going to use to then create our random data. So this is going to be the test scores. I'm going to say that the mean is 75. So we're thinking about a test situation. Notice I'm going to be writing this not in percent. So I'm just going to be putting a 75 instead of 0.75 or 75 percent. So we're talking the scores can be going from, you know, zero to 100, representing zero to 100, not in percent or decimal format. This is going to be the standard deviation, which you can represent with a sigma or I'm just might be putting sd to represent it in Excel because it's easier and faster to type. And then I'm just going to say that it's going to be 10. I'm going to use this data to then populate my randomly generated data. Now note in practice, of course, we wouldn't have all this information. If you were the instructor, you would simply be taking the test scores, plotting them out, and then finding based on that information, what the mean is, what the standard deviation is. However, if we're generating the random numbers, we can use Excel to give us that information, having an element of randomization in it. But we have to give them some characteristics such as a mean and standard deviation. I'm going to select the entire worksheet and bold this. You don't need to bold it yourself. But I like to have it bold for recording purposes, because you have to be bold. When you're recording, when you're on camera, you need to be you need to be bold. That's what I'm told by the producers and my editor here. So in any case, we're going to then say that we're going to take our data, and we're going to add our data. Now, if you don't have this analysis tool, then you're going to need that to generate the random data. So to do that, you can go to the file tab on the left, you can then go down to the options at the bottom. And then when it within the options, we want to have the add ins and then down here at the bottom, we've got the add ins. If you hit the drop down, we want the excel add ins and then say go. And then you want to check off that you have the analysis tool pack. And once you have the analysis tool pack in your tool belt, it's not that heavy or anything to when you have it in your tool belt, you know, so you can have it there. Then it'll be in the data tab analysis. And now you've got your data analysis. So I'm going to be putting it right here. So I'm going to say this is going to be my random data. Now it's not totally random because it's going to be in accordance with the bell curve, right? But we're going to say let's format this home tab. Let's go to the bucket black and white. This is my normal header formatting. I'm going to wrap it home tab alignment, wrap it, wrapping it random data. That was my rap of it. That wasn't a very good rap didn't rhyme or anything. I'm going to go to the data analysis up top. And then let's go down to random number generation random number generation. All right, so the number of of variables I'm just going to put one that's like the columns we only need one number of random numbers. So how many numbers do we want? Let's say like, let's say like 500. We have 500 numbers. Actually, let's just make it larger just to let's make it a thousand. That'd be a good lot of data there. So we're going to say that the distribution, this is the key we want it in accordance with the normal distribution. So normal distribution. And then when you do that, it gives you the parameters that are necessary. We need the mean or the average. Now again, in real life, you wouldn't have that because you're going to generate the data looking at the test scores in order to get the average. But here we have it because we need those parameters that doesn't remove the randomness, but it's a randomness that's controlled randomness. So standard deviation is going to be the 10. That's going to be giving us the spread, right? All right, so that's going to give us our data, the random seed. I don't need anything there. The output is I'm going to put it right here. So this is going to be the location of the output. I want it to start right there. So I want it in this worksheet right here on D two. So D two, just like our two D two and our two D two that he's from Star Wars gave us the numbers. So there we have, there's our randomly generated numbers. And that's great. So now let's run some calculations. So we're imagining if this was real life, this is all we would have this random number generation from rent from past test scores, we probably wouldn't I'm going to make this smaller. We probably wouldn't have 1000 test scores. But we might if we've been doing if we've been teaching for a long time, we've got a lot of test scores. But we're going to we're going to take this data and now do our calculations on it. So that would normally be that we would want the mean or the average. So let's take that. I'm going to then say this is going to be equal to the average. We've seen these. So I'm going to do these fairly quickly. This is a average. And then I'm going to hold down control shift. I'm holding control shift and down to take me right down to the bottom of the data set and enter and boom, double clicking on it. There is our formula. There is our answer. It's 75%. What do you know? That's what we put in the random data thing. So home tab, that's not how it is these days because they inflate the scores, man. It's not really 70. So if I add some decimals, it's 74.92. B is a C these days because it's it should be around 70 in any case. That should be the average 70 is average, right? Not not no, they totally inflate it now. That's what I hear at least. I don't know. I'm out of it these days. Standard deviation, standard deviation, but you can test that stuff out with your statistics, right? If you have the data, which they probably hide the data, but standard deviation is going to be standard deviation of the population. I'm going to say I'm going to say control shift down and enter. And so there we have 10. I'm going to add some decimals home tab number group, adding a couple decimals there. Now I'm also going to add the median. So the median that's the middle number. So the average is adding them all up dividing by the number of them, which was 1000. This one is going to take the one in the middle, just like Rocky's coach told him when Rocky saw three of Drago's out there, which the Russian guy, he said hit the one in the middle, which was good advice. So we'll do so we should keep that in mind.