A researcher wanted to test the study-time hypothesis. She randomly assigned 30 students to study a passage for 10 minutes and another 30 students to study for 20 minutes, and then had all of the students answer 10 multiple-choice questions to test their memory of the passage. She tested all participants in her quiet laboratory. The independent variable is the:

Question

Quizplus · Accepted Answer

The independent variable is the variable that is manipulated by the researcher, and in this case, it is the amount of time for study. The researcher randomly assigned participants to either study for 10 minutes or 20 minutes, which makes time for study the independent variable. The other options - number of questions answered correctly, quiet conditions in the laboratory, and number of participants - are not independent variables because they are not manipulated by the researcher.

A Researcher Wanted to Test the Study-Time Hypothesis