John is a waiter.He wants to determine if how he greets his customers (specifically whether or not he introduces himself by name)affects his tips.In this situation,the independent variable would be ________
A)the size of John's tips
B)the number of repeat customers
C)the presence or absence of John's name in his greeting
D)whether or not John's customers address him by name

Question

Quizplus · Accepted Answer

The independent variable is the variable that is manipulated or changed by the experimenter in order to see how it affects the dependent variable. In this case, John is manipulating whether or not he introduces himself by name, so this is the independent variable. The size of John's tips and the number of repeat customers may be affected by this variable, but they are not the variable that is being manipulated. Whether or not customers address John by name is not something that John can control, so it is not the independent variable.

John Is a Waiter