The heatmap is one of the hot new visualizations that were recently introduced in the latest Minitab Statistical Software. Heatmaps can help you visualize the impact of many categories on a numeric value and are an excellent choice for seeing details when dealing with larger datasets.
Some key benefits of heatmaps in Minitab include ease of use, interactivity, flexibility and best of all the results are easy to understand. Heatmaps also offer a simple way to identify patterns or quickly detect extreme values in data.
These graphs allow for the visualization of up to 10 categories on a numeric metric. The color gradient on the heatmap is automatically displayed based on the summary statistic you select, such as the mean or sum of the numeric metric. The gradient colors represent higher values of the summary statistic in red, and lower values in blue.
Let’s take a look at five hot uses for heatmaps.
Use #1: Customer Churn
Use CART® (Classification & Regression Trees) in Minitab to build a model that predicts the likelihood of customer churn. The heatmap below displays the churn probability predicted by the model and is based on five of the important predictors identified by CART’s Relative Variable Importance graph. Based on the color gradient, darker shades of red represent customers at higher risk of churning, whereas customers that are less likely to churn are represented in blue.
Hovering over the colored groupings on the heatmap automatically displays a tool tip that provides greater details about the categories on the graph as well as the summary metric for that particular combination of categories.
Use #2: Patient Length of Stay
In healthcare, a heatmap can be used to visualize patient length of stay based on patient type and demographics. In this heatmap, we see that inpatients with a discharge code of SNF (Skilled Nursing Facility) that are represented in dark red have a higher average length of stay compared to other patient groups.
Use #3: Project Management
In this example, an organization used Minitab's calculator to determine the number of elapsed days between the start and end date of projects in their portfolio. The heatmap below displays the sum of total days to completion by region and project type.
Use #4: High-Expense Areas
A heatmap provides a quick way to identify high expenses. Minitab's heatmap offers an interactive scrolling feature, so it's easy to visualize a lot of details when there are many levels associated with the categories on either side of the graph, which in this case are the U.S. states displayed on the left side of the graph.
Use #5: Time-Ordered Data
A heatmap offers a convenient way to display time-ordered data by a category grouping. In this example, we see call times by call type for each month in 2017 and part of 2018.