Bar Charts and Point Plots Video Lecture Transcript
This transcript was automatically generated by Zoom, so there may be discrepancies between the video and the text.

16:18:24 Hi! Everybody! Welcome back in this video. We're gonna keep going to continue to learn about different chart types and tableau in particular, we'll learn about bar charts and then the point plot equivalent of a bar Chart.
16:18:39 So let's go ahead and get started. So remember both.
16:18:42 I believe we talked about this. Maybe in Cabor or Matt Plotland, but both of these are ways that you can visualize summary statistics.
16:18:48 So you can, for instance, plot the heights, the average heights, or the Median height, or something, or the average body mass.
16:18:57 And these examples of different penguins, based on different categorical variables, like the species of penguin.
16:19:04 So let's go ahead and dive into the tableau to see this in action.
16:19:09 So the data file that we're going to be using is the penguins dot Csv data file.
16:19:16 So this comes from Seaborne originally, but I've downloaded it as a Csv.
16:19:20 And put it into our data repository folder of the Repository.
16:19:24 So we can use it in tableau. So here we are in our worksheet, and if we're trying to copy the ones here, we're gonna want species on the horizontal axis and average body mass on the vertical, so well, if by now, we're familiar enough with tableau that
16:19:40 we could do this. So we first take species and drop it on either the top or the columns.
16:19:46 Okay, so we have got Adelaide Chinstrapped into.
16:19:51 And then we take the body mass, measure and place it in the rose bar.
16:19:56 So currently, it is as a sum. But we can go ahead and aggregate that measure to an average instead.
16:20:04 And further, if you'll notice, we can spread it out a little bit if we'd like.
16:20:09 Okay, so now I've got our. We've made our bar chart.
16:20:13 It's just that easy. It's that straightforward.
16:20:17 We could change the color of the bars. Maybe we want them to be a light blue and to be outlined as well.
16:20:24 So let me move my picture. It just keeps getting in the way.
16:20:27 So, if we change it to light blue by clicking on the color marks.
16:20:32 But maybe we also want to add an outline. So go to border and then click on it and click black.
16:20:38 And I've got a nice black outline as well let's see, what else could we do?
16:20:43 So we could sort them if we'd like. So if we click here, let's see.
16:20:50 So if we click here, we can sort them so that they're in increasing order or decreasing order, just by clicking on the little icon next to average body mass.
16:21:01 And you can also see that there's a sort here button that works as well, and then it gives you an idea of how you'd like it to be sorted as well.
16:21:10 Okay, so what else can we learn here? We can learn about, for instance, maybe we want to see the different sex determine the color.
16:21:21 So the sex of the penguins, and you'll notice here that there's a couple things.
16:21:27 So first, what it's doing, because it's in this automatic.
16:21:29 It's automatically going ahead and breaking the bars up and so when you have a bar chart and you're trying to add color to it and tableau, what it will automatically do is break it up the bars like this instead of having them, left we'll see how to make that
16:21:48 plot in a little bit, but if we wanted to, for instance, get rid of those null values, we can go ahead and add a filter here.
16:21:57 So to add a filter, we can drag the variable that we'd like to be filtering.
16:22:02 And then it will say, Select from list. So we get rid of the null, and then, now it's left for those penguins for which we have an observation for okay, so the next thing we can do is this is a bar chart we'll learn a little bit. Later.
16:22:22 How to go ahead and plot these bars one next to the other, and maybe, you know, we don't like orange and red.
16:22:29 So we can go to color. And instead change it to be.
16:22:33 Maybe instead of orange and red, we can make female be gray or something.
16:22:40 Okay, all right. So this is a bar chart. But how could I change it to a point plot?
16:22:46 So, instead of the bars I could do circles. Okay?
16:22:51 And then I could change the size of the circle, because that's a little big.
16:22:54 Or I could do the line version right, and then I could change my markers to have the circles.
16:23:01 But again I think that this is a little, I find the markers to be a little hard to read here, so why don't we go back to the regular circle?
16:23:11 Hey? And again. Nice to meet you.
16:23:19 Okay. So now we've seen how to make a regular, a simple, straightforward bar chart and a point plot.
16:23:25 Another thing we could do if we'd like to alternate between different part plot types is to click on.
16:23:32 Show. Me, and we could go back to so what we're currently looking at is horizontal bars.
16:23:39 We could go back to that if we'd like, and now you'll see it's kind of broken up.
16:23:44 This is what we had before, where these were stacked to bar so we clicked on stacked bars.
16:23:49 Similarly, we could get some side by side bars where it's got the sex and the species, and we can see how that changes if we change the order up top.
16:23:59 So if we wanted mail and female here to be for stratified by species, we could go ahead and do this and then you'll see it's automatically coloring by species.
16:24:12 But maybe I don't like that. I'd rather see it colored by sex.
16:24:17 Okay, so now you can see how to how this works.
16:24:22 Now, we've made our side by side bar as opposed to the stacked bar, and so we've seen how show me can be used to alternate between different chart types.
16:24:31 And this is a common thing. We'll keep doing as we go through.
16:24:34 Okay. So the last thing I want to show in this video is something called hierarchies.
16:24:39 We'll learn more about these and see them in action and more lectures later. But I want to introduce them.
16:24:43 Here so we can create a hierarchy. So a hierarchy is like an ordering of dimensions, so we can go ahead and create one by taking one dimension and dragging it on top of another.
16:24:55 So let's say that we want to have the hierarchy.
16:24:58 The species followed by sex, so if I want to do that, I take this sex dimension, drag it on top of the species and now you'll see that I've got a create hierarchy pop-up species coma sex.
16:25:11 And now what this does is, it's going to order it and break down the penguins into groups, first according to species, and then according to the sex.
16:25:20 So we can see this has already been aied on to our charts by looking up here at the columns.
16:25:26 You see this little box with a if I go ahead and click that it will then collapse back into the species, and it's colored still by sex, because I have the coloring on that.
16:25:38 But if I took the coloring out it would just be the normal bar chart.
16:25:41 If we want to put the coloring back in, we can do that as well but let's go ahead and see what happens.
16:25:48 When earlier, I hit the minus button. But now, if I hit the plus button we'll get that chart back earlier where first it's broken down by the species.
16:25:55 Adelaide Chinstrap engine, and then it's broken down by the subgroup which is been determined to be sex. In this example.
16:26:04 And again, if we want to re-AD in that color to help identify between male and female more quickly, we could just drag sex back over to the color.
16:26:13 Okay, so we've learned how to make a bar chart.
16:26:16 We've learned how to take that chart and then turn it into a point chart with the with the changing, the marks we've seen more examples of how to use dimensions to change color.
16:26:28 I should also, let's quickly point out that if I do get rid of the sex, you can also use a continuous, variable, an aggregate of of a measure.
16:26:39 So maybe, instead of that, I wanna do average average bill down so we can color that as well I'm gonna take that away.
16:26:47 Cause. That's not how I want to save the final version.
16:26:51 But I'm just showing you that you can color by continuous measures as well.
16:26:54 We saw how to use filters by dragging these onto. They're dragging a dimension.
16:27:00 You can also do it with a measure as well, but dragging these onto there and then filling out the pop-up, we also learned about hierarchies with making a species subgroup by sex, and hiierarchy, and we've done.
16:27:14 And we showed how you can switch between different chart types using.