posted by ash on .
A researcher investgating depression devises a study that contains the independent variable "Treatment," manipulated between-participants. Participants may experience "psychodynamic therapy," "cognitive behavioral therapy," "medication," or "waiting list placement." How many levels does the variable contain?
a) There are four levels to the variable.
b) There are three levels and a control condition.
c) There are four levels and "Treatment," making five.