Consider the following scenario: a pro-life group wanted to test the effectiveness of an anti-abortion commercial. Two random samples, each of 250 respondents, were recruited in Atlanta. One group was shown the anti-abortion commercial. Then attitudes toward abortion were measured from respondents in both groups:
Identify the independent and dependent variables in this experiment.
Identify what type of research design was used.
Identify potential threats to internal and external validity in this experiment.
If the respondents had been chosen by convenience, rather than randomly, what type of research design would result?