Question

A researcher posts a radio advertisement offering $35 in exchange for participation in a short study. The researcher accepts the first eight people who respond to the advertisement. Which of the following statements is true about the sample? (5 points) a It is a valid sample because the first eight people were selected to participate. b It is not a valid sample because it is not a random sample of the population. c It is a valid sample because money was offered to participants. d It is not a valid sample because it is only a short study.

Answer 1

B) not valid because it is not a random sample

a) is biased because the first 8 people are unlikely to be representative of the population
c) is biased as offering money will influence the people who reply
d) is untrue because short studies are valid if they are representative