Use Heatmap to compare the means or other summary statistics using a color gradient to represent the impact of different groups.

For information about data considerations, examples, and interpretation, go to Overview for Heatmap.

Categorical row variables

Enter up to five columns where the categories are represented as rows on the heatmap.

Categorical column variables

Enter up to five columns where the categories are represented as columns on the heatmap.

Summarized variables (optional)

Enter a column that defines the color gradient of the rectangles in the heatmap. If you enter multiple columns, Minitab generates a separate heatmap for each variable that you enter.

Function

From Function, select the function of the Summarized variables. For example, if you select Maximum, Minitab defines the color gradient for the heatmap based on the maximum value of the summarized variables in each rectangle. If you enter a text column in Summarized variables, you can only select Percent equal to specified values, Number of nonmissing values, or Number of missing values.

Some options require you to enter additional values.
Percentile
If you select Percentile, you must enter a value in Percentile value. The value must be between 0 and 100. Minitab uses the value you enter to define the color gradient in the heatmap. For example, if you enter 50, Minitab uses the 50th percentile to define the color gradient for each rectangle of the heatmap.
Percent between two values
If you select Percent between two values, you must enter numeric values in First value and Second value. The value you enter for First value must be less than or equal to the value you enter for Second value. Minitab defines the color gradient for the heatmap based on the percentage of observations that is between the two values.
Percent equal to specified values
If you select Percent equal to specified values, you must enter one or more values in Values. The values must be the same type of data as the column you entered in Summarized variables. Minitab defines the color gradient for the heatmap based on the percentage of observations that is equal to the values that you enter.

By variables

Enter one or more grouping variables in By variables to create a separate heatmap for each level of the grouping variables. The columns that you enter must be the same length as the columns in Categorical row variables and Categorical column variables. The y-scales for each variable are the same across the multiple heatmaps.
Show all combinations

When you enter multiple By variables, Minitab enables the Show all combinations checkbox. Select this option to create a separate heatmap for each combination of groups created by the By variables. If you do not select this option, Minitab creates a plot for each group of each By variable.

For example, the first By variable has two groups, Male and Female, and the second By variable has two groups, Employed and Unemployed. If you select Show all combinations, Minitab creates four separate plots for the combinations of Male/Employed, Male/Unemployed, Female/Employed, and Female/Unemployed. If you do not select Show all combinations, Minitab creates four separate plots for Male, Female, Employed, and Unemployed.

Gradient type

Select the color scale for the rectangles.
Diverging
Rectangles with high values are red, and rectangles with low values are blue. In Gradient symmetric around value, enter a value to center the gradient scale at a specific value rather than the center of the function that you selected.
Sequential from low to high
Rectangles with high values are dark blue, and rectangles with low values are light blue and light gray. You can use this option to highlight rectangles with more productivity or to maximize revenue.
Sequential from high to low
Rectangles with low values are dark blue, and rectangles with high values are light blue and light gray. You can use this option to highlight rectangles with low defect rates or to minimize cost.

Same gradient scale

When you enter multiple columns in Summarized variables, select this option to use the same gradient scale for each heatmap created for the different columns.