Random assignment is used in experiments because researchers want to
A) guarantee that the results will be statistically significant.
B) ensure that people from different social classes will be in separate groups.
C) ensure that the experimental results are not merely correlational.
D) reduce the likelihood that the experiment's results will be due to any preexisting differences between the experimental and control groups.

Question

Quizplus · Accepted Answer

Random assignment helps to reduce the likelihood that any preexisting differences between the experimental and control groups will influence the experiment's results. This is important in order to establish a causal relationship between the independent variable and the dependent variable. Random assignment does not guarantee statistical significance or separate people from different social classes into separate groups, but it does help ensure that the experimental results are not merely correlational.

Random Assignment Is Used in Experiments Because Researchers Want to