CHAPTER 2

 

WHAT IS AN EXPERIMENT ?

*** An experiment is a study where you manipulate one variable and measure

the resulting behavior

A. The independent variable is the one manipulated by the experimenter

(sometimes called a factor)

*** The IV is the "cause"

*** A specific category of the IV is a condition of the IV

(also called a level or treatment)

*** A condition of the IV is determined by random assignment

*** The control group receives a zero amount of the IV

*** The experimental group receives a nonzero amount of the IV

*** Can use confederates to manipulate the IV

B. The dependent variable is the one you measure and you hope changes
*** The DV is the effect

*** The DV is the behavior of interest

C. Can have an intervening variable that exists between the IV & DV

*** Most common one is "thinking"

*** A quasi-experiment is when you can't manipulate the independent

variable (must take the preexisting value)