Question

A research assistant randomly selected 75 undergraduate students from the list of all students enrolled in the psychology-degree program at a large university. She asked each of the 75 students, “How many minutes per day do you typically spend reading?” The mean reading time in the sample was 89 minutes, and the margin of error for this estimate was 4.28 minutes. Another research assistant intends to replicate the survey and will attempt to get a smaller margin of error. Which of the following samples will most likely result in a smaller margin of error for the estimated mean time students in

Answer 1

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Answer 2

The more 'samples' you have, the smaller margin of error you have.

So 300 randomly selected is better than 40 randomly selected.

Now the second part is about whether you should selected psychology-degree program students or not.
Since our original sample was from the psychology-degree program, we should do the same thing.

So we would select the answer with the MOST randomy selected students, from the psychology-degree program students.

Answer 3

Why can't we have undergraduate students from all degree programs at the college?

Answer 4

Because then original one was from the psychology program, so the study here focuses only on our psychology-program students. It's the population.

If the surveyor were to study the population of the entire campus, he wouldn't have just chosen students from the psychology-program.

Answer 5

Oh okay. Thanks!