In an experiment, it is essential that
A) the group sizes are equal.
B) the experimental and control groups are comparable at the start of the study.
C) all participants are given a pretest.
D) the groups are equal after the manipulation.
Question 2
Which of the following is essential for a successful control-group design?
A) that the experimental and control groups be comparable at the start of the study
B) that participants be randomly selected from a general population
C) that at least three conditions are manipulated
D) that there be an equal number of male and female participants
Loewi's experimental discovery of chemical neurotransmission.
Elements of an Experiment
Using child-sized dishes at mealtimes can help caregivers monitor portion sizes
Created Equal: A Social and Political History of the United States, Brief Edition
Miller's Experiment
The Hershey-Chase experiment