In a study with two independent variables, such as the word frequency study, the when one variable (such as priming) affects the other variable (such as word frequency) differently depending of the value of the second variable, it is called a/an:.

Ongoing civil wars western roman empire finally collapsed476 c.e. romulus, the last of theroman  emperors in  the west, was overthrown by the germanic leader odoacer, who became the first barbarian to rule in rome. the order that the  roman empire  had brought towestern  europe for 1000 years was no more.