Find interpretation guidance for the interaction strength tables.
The top 2-way interaction strength tables identify the pairs of variables
that have the strongest interactions. The interaction tables display the % of
total squared error and/or the % of squared error for the strongest 2-way
interactions. Use the % of total squared error to describe the strength of the
interaction relative to the variation in the data. Use the % of squared error
for the specific pair of variables to describe the strength of the interaction
relative to the strength of the main effects of the variables.
Interactions are not possible when a tree has only 2 terminal nodes. Thus,
the maximum terminal nodes per tree must be 3 or larger. You can set this on
Minitab does not display the interaction tables if all interactions
have a % of total squared error or a % of squared error less than 10%.
In this example, the eight strongest 2-way interactions are the same for
both tables; however, the ordering varies slightly. In the first table, the
interaction between Annual Income and Front End Ratio is the strongest 2-way
interaction. The percent of total squared error is 11.71977 which means that
11.71977% of the total squared error is explained by the main effects of Annual
Income and Front End Ratio and their 2-way interaction effect.
For the same 2-way interaction between Annual Income and Front End Ratio,
the percent squared error for the predictor pair with main and interaction
effects is 19.73464%.