#14 - A survey of alumni of the class of 1960 at Aurora

[Administrator]

Complete Question Explanation

Resolve the Paradox. The correct answer choice is (A)

This stimulus involves the “puzzling” survey results which had half the respondents saying that they were in the top quarter of the class. This would likely be explained in one of two ways: either students’ memories inflate their perceived past accomplishments, or perhaps those who had been in the top quarter were more likely to respond. Such a self selecting sample would explain the survey results.

Answer choice (A): This is the correct answer choice, and restates the prephrase above. If the academic achievers were more likely to respond, then their high ranks would be over-represented by the survey.

Answer choice (B): This choice does not resolve the paradox—it actually rules out one possible resolution (the first prephrase from the discussion above). If we know the survey responses to be accurate, then the disproportionate numbers are even more confusing.

Answer choice (C): We don’t know how well the other groups were represented, so this consideration is irrelevant, and fails to resolve the disparity between the portion of respondents and the quartile each one represents.

Answer choice (D): Like incorrect answer choice (B) above, this choice actually expands the paradox, by ruling out one possible explanation—that of an unrepresentative survey.

Answer choice (E): Regardless of how they determined class rank, the paradox remains between the portion responding and the overrepresentation of the top quartile.

[lsatloverrrrr]

Is Answer A correct because an unusually large amount would skew the results? Wouldn't the difference be attributable to the students being mistaken (like in Answer C)? How would a disproportionate number of respondents resolve the paradox if there's only a select number of alumni in the class of 1960?

[Jeff Wren]

Hi lsatloverrrrr,

This question involves a paradox concerning the results of an alumni survey. According to the survey, half of respondents reported that they were in the top quarter of their class. This seems odd because one would expect that the proportion should be that roughly one quarter of respondents would report that they were in the top quarter of their class.

One possible explanation is that some people were mistaken about their class rank or even outright lied about their class rank.

Another possible explanation is that the people who answered the survey were not a representative group of the entire class. For example, if most of the people who answered the survey just happened to be in the top quarter of their class, this would explain the results even if the survey respondents were not mistaken and were not lying. Answer A describes this explanation. A "disproportionate number" means that more of those people answered the survey than what would be expected based on their actual proportion in the group. For example, even though the top quarter of the class represents 25% of the class, people who were in the top quarter of the class may have been 50% of the people who answered the survey. While there is certainly a limited number of students who graduated in the class of 1960 at that university, not every graduate answered the survey. What Answer A is describing is that, of the alumni who did answer the survey, people in the top quarter of their class were more likely to answer the survey than the rest of the class.

While the students who responded to the survey being mistaken about their class rank would help explain this paradox (as mentioned above), that is not what Answer C says. Answer C states that "not all the alumni who were actually in the top quarter responded to the survey." This does not mean/imply that the students who did answer the survey were mistaken. Remember, not everyone in the class answered the survey. For example, it's possible that as few as 1% of the class answered the survey. The fact that some of the alumni who were in the top quarter of the class did not respond to the survey does not mean that the students who did respond were mistaken about their own class rank.