Population and Sample - Confusing Test Question

Question

I got this question in the first week of Intro to Statistics:

"A survey of 12,075 women in a particular country found that 46.9% received an influenza vaccine for a recent flu season. Identify the population and the sample.

Identify the population:

A. The 12,075 women selected

B. All the women in the country

C. The collection of immunization statuses of all the women in the country

D. The collection of immunization statuses of the 12,075 women selected

I said B was the population, the correct answer was C. Can anyone explain this to me?

Population and sample are the things we’re seeking data about, so how can the data itself - immunization status - BE the population?

Answer 1

You are right. It is confusing and a poorly written question. What is NOT being said in the question is that according to the answer, the survey was NOT made of the women but of their immunization records.

We know this NOT from anything in the question or the proposed responses, but in the answer they gave AFTER a selection was made. In other words we can deduce by inference that the immunization status's were sampled, not the women themselves. (say from doctors records). We can only make this decuction AFTER we know the right answer so the question is faulty.

If the women were themselves questioned about their immunization status than that would be the population.

I suggest you confront the instructor and ask from what information in the question can one make the assumption that only the records were surveyed, not the women. Especially as the question was very specific "In a survey of 12,075 WOMEN" . no mention of the survey being made of the women's records.

as a side note, nothing is included to state that anything other than 100% of women have immunization records [i.e. nothing to refute that is mentioned]. In that case the population of women's records and the population of women, in this context, are identical populations. Tsk Tsk.... such poor wording.,

That being said, this happens even more in real life. A boss asks for one thing, thinks they are asking for something else, and interpret the results as a third thing and then thinks they are all the same when they are not. Happens all the time.