A tendency to say what you have just heard illustrates formal control. For example, someone says, “say alligator” and you then say “alligator.”
When a controlling variable evokes a response and has the following features:
There is point-to-point correspondence between the controlling variable and the response
Whether or not there is formal similarity between the controlling variable and the response
Formal characteristics of either the controlling variable or the response
Dynamic characteristics of either the controlling variable or the response