Dr. Street wants to measure the effects of watching a movie on mood. He asks students to select either a comedy or a tragedy to watch in a controlled setting.
He administers a mood test afterward and finds that the comedy group is significantly happier than the tragedy group. Dr. Street cannot make a causal statement about the effects of movies on mood because
A) he failed to manipulate a variable.
B) he failed to include a dependent variable.
C) he failed to randomly assign participants.
D) he found no correlation between movie and mood.
Question 2
When every participant in an experiment has an equally likely chance of receiving any one of the treatments, the researcher is using
A) independent assignment.
B) random assignment.
C) direct assignment to condition.
D) systematic assignment.
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