"Is there an interaction or not?", "How big is the interaction?" One example of this is to analyze with a model using Interaction terms.
This page is a type that does not use interaction terms.
The factorial effect diagram is a method that can be used when there are few variables, and one variable is qualitative. You can handle any type of interaction, and you can see which type it is.
The Decision Tree divides the cases and derives the features of Y.
It is not suitable for judging "Is there an interaction?", but it can handle any type of interaction. It can be used for analysis that "even if this condition is met, it has a special effect".
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Path Analysis
