Logical reasoning PrepTest 146 · Section 2 · Question 22

Incorrect. This argument continues to establish a pattern of those watching themselves exercising and then exercising more; it also establishes that they did exercise instead of just reporting that they did. This argument is more in the direction of supporting the argument.

Incorrect. While a study about giving to charity might be able to have an impact on a study about exercise, the parallels would need to be pretty strong. But here, they're not, since there's no parallel in the stimulus to hearing stories of people you identify with donating to charity.

Incorrect. This answer choice seems to be dealing with the potential sampling flaw, but it doesn't talk about how these individuals were split between the groups, so it doesn't provide enough information to know what impact it has on the argument.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
Group 1: Watched themselves running on treadmill. Later, exercised more.
Group 2: Watched someone else running on treadmill. Later, exercised less.
Conclusion: Watching yourself exercising causes you to exercise more.

Answer Anticipation:
There are two elements in this stimulus that warrant analysis for flawed logic.

The first is the study itself. The study wasn't established to involve large, representative, random groups. In particular here, there's no indication that Group 1 didn't already exercise more than the first group. Additionally, the amount of exercise was self-reported, which always raises the possibility that those numbers are wrong (either a lie or a misperception).

The second is the causal conclusion ("can motivate you"). It is based on a correlation, so this argument also has a correlation/causation flaw (if the people actually did exercise more). When that flaw shows up in a Weaken question, correct answers will generally:

(1) Raise an alternative cause
(2) Show counterexamples (cause without effect; effect without cause)
(3) Bring up reversed causality (unlikely here, as exercising in the future couldn't cause someone to watch themselves exercise in the past)

Answer Explanation:
Similar to (B), a study in a different area might have an impact on this study, so we can't throw this out just because it's about reading. And observing an identical twin reading isn't too far from watching a video of yourself exercising. This answer then goes on to suggest that people overreported how much they read over the next few days. If seeing yourself (or someone who looks exactly like you) can result in you overreporting how much you read, then it's possible that watching yourself exercise can result in you overreporting how much you exercised. This answer choice undermines the stimulus by suggesting that relying on self-reporting of positive behavior (exercising, reading) can lead to reports that aren't accurate.

Key Takeaway:
What a question! If you were focused on the correlation/causation flaw, you would have missed the correct answer, which is hard enough to spot even if you're looking for the sampling flaw.

But the biggest takeaway here is that a study relying on self-reported results is always suspect, so be sure to take into account how this information is collected.

Incorrect. If anything, this would provide more examples of people watching themselves do something and then doing more of that thing in the future, thus strengthening the argument.