Comparing subsets of data

We saw in Chapter 1, Welcome to Spotfire, that trellising can be used to compare different subsets splitting the data by the values in various columns. Spotfire's Subsets feature allows for the comparison of subsets by filtering, marking, or a custom expression. Let's go through an example together. For the example, I have chosen the same US vehicles dataset that I first used in Chapter 5, Practical Applications of Spotfire Visualizations. You can follow along in your own dataset!

Here's how you can compare subsets of data in Spotfire:

1. Create a visualization. For this example, I have produced a visualization showing Mpg City per Transmission Type:

Recall that Mpg City is the measure of fuel economy when a car is being driven in city traffic. Higher Mpg is better.

2. Open the visualization properties and navigate to the Subsets page.
3. Select...