1. A tour of the interface
Now that you’re familiar with the most important Tableau terminology, let’s see Tableau’s interface in action.
We currently have a blank worksheet.
In the data pane, we have our San Francisco data loaded, with its dimensions and measures. Remember blue fields are discrete, and green fields are continuous. The data type icons you saw on the Data Source page when loading the data also appear here. Notice Tableau automatically generated new fields for us, shown in italic: measure names, the number of records (given by san francisco dot csv (count)), and the measure values.
We’d like to know which neighborhoods have the highest number of reviews. So let’s focus on neighborhoods first. When you start dragging a field, some places are highlighted in orange. These are all the places we can drop our field on. Let’s drag it into rows. Whether you drag it here or here has the same result.
Then, we would like to see the total number of reviews for each of neighborhoods, so we drag the number of reviews to the text card, and we get the number of reviews per neighborhood! Notice how by default, Tableau takes the sum of the data. If you click on the down arrow, you can change the measure's aggregation: you could use the average, or the maximum, for example. Sum makes sense in this case, so we keep it that way. You could also drag the number of reviews field to size instead, or color. Tableau automatically adds a legend. We’ll stick with text for now.
In the toolbar, you have different buttons. This one gets you back to the Start Page. This back arrow lets you undo your changes, and this one allows you to clear your sheet to make it blank again.
Currently, you can see that Bayview has a total of 6,119 reviews.
Let’s now find out the number of reviews for listings under $200 a night. To do that, we use the Filter shelf. We will get into more detail about filters in a next chapter. For now, you just drag the price field onto the Filter shelf. The popup window offers several ways to aggregate the data. We want to consider all values, which is selected by default, so click next. You then input a range of values from 0 to 199. Let’s apply it: our values have changed. Bayview now has 5,137 reviews for listings under $200.
To remove a field, just drag it out until you see a red cross appearing, and release.
Now imagine you would like to know the number of reviews in each neighborhood for each room type. You just need to drag the room type to rows. See how dimensions help you segment the data into groups. Now you see that Bayview has 2,807 reviews on entire homes, 3,311 reviews on private rooms, and just one review for shared rooms.
Now if you find that overwhelming, you can drag neighborhood to Pages. We now have a page for each neighborhood, and we can navigate through each neighborhood separately. You can also use the drop-down menu to find a neighborhood directly.
Time for you to try it out in the exercises!
2. Let's practice!