A researcher posts a magazine advertisement offering $30 in exchange for participation in a short study. The researcher accepts the first three people who respond to the advertisement. Which of the following statements is true about the sample?

It is not a valid sample because it is not a random sample of the population.
It is a valid sample because the first three people were selected to participate.
It is a valid sample because money was offered to participants.
It is not a valid sample because it is only a short study.

Question

A researcher posts a magazine advertisement offering $30 in exchange for participation in a short study. The researcher accepts the first three people who respond to the advertisement. Which of the following statements is true about the sample?

 It is not a valid sample because it is not a random sample of the population.
 It is a valid sample because the first three people were selected to participate.
 It is a valid sample because money was offered to participants.
 It is not a valid sample because it is only a short study.

blm1 · Answer

It isn't the third or fourth one I know

blm1 · Answer

@peachpi

blm1 · Answer

@welshfella

anonymous · Answer

it's the 1st. 
The 1st three people who reply isn't random, it's sequential

blm1 · Answer

Thank you, that's what I was going with! :)