#3 - A recent study proves that at least some people possess

[Administrator]

Complete Question Explanation

Strengthen. The correct answer choice is (C)

Because subjects decided correctly 60 percent of the time whether they were being watched through the window, the author concludes that at least some people have an independent "sixth sense" that allows them to detect whether someone is watching them.

The cause-and-effect relationship between the study's findings and the proposed result can be summarized as follows:

• Cause Effect
  
  Sixth sense Feeling of being watched

To strengthen the argument, examine any alternate causes that might limit the applicability of these findings: maybe the subjects could hear the conversations of those watching them behind the window, or even see their shadows. Maybe the sample size was too small to be representative and the subjects merely "lucked out" in their guesses. If you can figure out why the conclusion does not necessarily follow from the premises, you will be much better off when asked to find an answer choice that strengthens that conclusion.

Remember: in causal arguments involving surveys, the most typical Strengthen answers are the ones eliminating plausible alternate causes for the stated effects, or those ensuring that the survey in question was representative and unbiased towards the proposed result.

Answer choice (A): If subjects said they were being watched most of the time and 60% of the time they turned out to be right, such a finding might suggest that the 60% accuracy rate is a function not of any extrasensory perception but rather of the frequency with which they were being watched. Imagine the results of the study if the subjects were being watched only 20% of the time: if they always reported feeling watched, the accuracy rate would suddenly plummet to 20%. This answer choice does the exact opposite of what is needed and is incorrect.

Answer choice (B): Whether the person conducting the experiment interacted with them after the end of the experiment is irrelevant, as there is no indication that the subjects were asked to report on how they felt after the completion of the experiment. Even if they were, the absence of such interaction only guarantees that subjects weren't given clues as to whether they were watched or not, and provides only limited support to the conclusion. Remember: your job is to find the answer that most supports the conclusion.

Answer choice (C): This is the correct answer choice. The best way to strengthen the author's conclusion is to show that another experiment — ideally one that fixes some of the potential problems with the first one — revealed similar results. If subjects were watched from another room on a video monitor and reported a similar result, this would eliminate many of the alternate causes that plagued the results of the first study: for instance, it is no longer possible that subjects overheard the conversations among those watching them.

Answer choice (D): If the room was not soundproof, maybe the subjects overheard being watched. This answer choice does the exact opposite of what is needed and is therefore incorrect.

Answer choice (E): If the subjects were graduate students in psychology, this might suggest that the sample was unrepresentative of the population as a whole. This answer choice weakens the conclusion and is therefore incorrect.

[sa3334]

Hi,
I understand why C is the correct answer, but I picked A. Can you go into more details as to why A is incorrect?
Thank you!
SA

[Adam Tyson]

Take it to the extreme, SA, as our explanation did. What if the subjects said they were being watched EVERY TIME? If they were actually being watched 60% of the time, they would have a 60% success rate, but we wouldn't be very impressed. They only got that result because they were being watched that often, and not because they have extra-sensory powers.

Basically, without knowing how often they were actually being watched, coupled with how often they said they were or were not, this answer doesn't help us to strengthen the claims in the stimulus. We're left wondering if the study was good or not, and whether their success rate was due to actual abilities or to statistical anomalies or chance.

Answer C is so much better than answer A, and that's the best reason to reject A. If C is true, we have more data that corroborates the original results. More data is good! Also, you might be worried about the fact that the first experiment involves a window, and perhaps the subject could detect changes in light and shadow, so the second experiment is probably even better because it eliminates that possible "cheat." More data, from a possibly better experiment, is a great way to strengthen a claim that is based on an experiment. After all, we are supposed to pick the best answer, per the instructions!

[Nicholas Noyes]

So C is correct because it adds more data to prove the original results more accurate? I narrowed down my decision between A and C, but I just want to confirm because I originally picked A. Looking back at it now, doesn't A just state what is said in the stimulus pretty much, it doesn't necessarily strengthen the conclusion?

[Robert Carroll]

Nicholas,

Answer choice (A) does add information, but nothing particularly important for the argument. The subjects were right 60% of the time. Does the fact that more than half of the "guesses" were affirmative (in other words, they guessed they were being watched) relevant? It doesn't change the 60% accuracy rate. Imagine there were 100 subjects and each was tested once. Thus, any number from 0-100 of those test instances could have had a person watching. The stimulus tells us that 60% of the guesses were accurate. Does it matter if people were watching 100 out of 100 times, or 50 out of 100, or 0 out of 100? In any case, 60 guesses were right and 40 wrong. If it does matter, note that answer choice (A) doesn't tell us how the 60 correct guesses were distributed anyway, so I really don't see any reason the answer alone adds useful information to the stimulus.

Answer choice (C), on the other hand, adds extra information consistent with the conclusion, bolstering the argument.

Robert Carroll