Step 6: Style a dataset to create a map

It's great being able to look at a dataset, but seeing a bunch of points, lines, or polygons isn't exactly useful. To make data relevant and useful for people, it needs to be styled in such a way to convey meaningful information. 

Using the Traffic Calming Features, the correct choice in styling can show information about two different questions. The first question is: "How recently were traffic calming features added?" and the second question is: "What type of traffic calming features are being used?"

In order to answer the first question it is important to inspect the data. Inspecting the data in the table view, reveals a field called install_yr. Using a choropleth style on that field will result in a map that can display the answers to the question.

To do this, deselect all records by clicking somewhere on the map. Then click "Show Styling Options", choose the "Choropleth" style. After that, select the field "install_yr", give it 7 buckets, and increase the size to 18 px. 

Doing this results in a Chorpleth Map that displays the most recent years as darker colors.

Looking at the data this way gives a few interesting insights. For example, it looks like it is common for traffic calming features to be installed along particular streets at the same time, and in some places, they have been adding traffic calming features almost every year, slowly spreading out along the street. 

To answer the second question, the "Category" style is most appropriate. Switch from "Choropleth" to "Category" and select the field "descript". That field is used to describe whether or not it is a Traffic Island, a speed bump, bulb-out, speed sign, et cetera. Increase the size to 16, and click "Save" to change the style. 

The resulting map shows a lot more colors than the Choropleth and also reveals some interesting information. It's a little overwhelming so we can also add labels to see it better on the map. Scroll to the bottom of the category pane and select "descript" as the label. Give it a label offset of -10 and click save to see the labels.

Looking at the data we can see some interesting things. One of the interesting things is that in most places there is not a mixture of traffic calming devices. One street will have lots of traffic medians, but no bulb-outs, or vice versa. 

In a couple of places we see that traffic islands are paired with speed humps

Bulb-Out's are used in groups 

 Once the data has been styled in a way to show the information you'd like to you can return to the dataset list and check "public map" in order to get a link that you can share with other people. 

Public map setting

Styled map (visit here)