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 Jeremy Press
PowerScore Staff
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#100752
Complete Question Explanation

Flaw in the Reasoning. The correct answer choice is (C).

The student's argument misinterprets the professor's stated criterion, thus the argument is flawed. Since the question stem alerts us to the presence of a flaw in the stimulus, even if you didn't notice it when you first read the stimulus, it is to your benefit to return to the stimulus to prephrase the flaw before working through the answers.

The professor's stated criterion is that she gives A's only to papers that have reliable statistical evidence supporting their conclusions. This is a conditional relationship, and it's critical to identify what the necessary condition is in that relationship. The "only" is the guide, flagging what follows as necessary. In other words, if you're going to get an A, then you must have reliable statistical evidence. Diagrammed: A :arrow: Reliable Statistical Evidence.

We must remember that necessary conditions can occur without sufficient conditions, and that the occurrence of a necessary condition is therefore never enough by itself to ensure the sufficient condition occurs. In other words, in this case, simply having reliable statistical evidence will not guarantee that the student gets an A.

But the student has mistakenly assumed that such reliable statistical evidence was going to be enough to get them an A on the paper, and that therefore the professor violated her criterion. This is a Mistaken Reversal (the faulty assumption that the occurrence of a necessary condition guarantees the occurrence of a sufficient condition).

The descriptions the test makers given to Mistaken Reversal flaws can sound a little convoluted, but they generally indicate that the author of the argument has mistaken (or confused) a necessary for a sufficient condition. Look for the language of sufficient conditions (language like "sufficient," "enough," "guarantee," etc.) and necessary conditions (language like "necessary," "required," etc.) in the answer choices.

Answer choice (A): Answer choice A suggests that the student is using the criteria to distract from the paper's shortcomings. This is incorrect partly because we don't know from the stimulus whether or if the paper has any shortcomings, and partly because we also know that the heart of the flaw is the misinterpretation of the criteria (the Mistaken Reversal), not the usage of it to distract from other issues.

Answer choice (B): Answer choice B is wrong because the student does not draw an "evaluative conclusion." An evaluative conclusion assesses the quality or value of something (in simple terms, how good or how bad it is). The student is rather drawing a factual conclusion about whether the professor broke her own rule.

Answer choice (C): This is the correct answer choice. This answer describes the mistake the student has made in treating the necessary condition (the reliable statistical evidence, i.e. "the requirements for a particular grade") as a sufficient condition (i.e. as "enough to guarantee that grade"). Notice the key language of necessity ("requirements") and sufficiency ("enough," "guarantee") in the answer choice.

Answer choice (D): While it may be correct to observe that the student has some bias (a personal interest in the outcome of the argument), that is not what makes the argument flawed, because neither the factual assertions the student makes (the criterion the professor uses, the fact that the paper got a B, the fact that the professor said there was reliable statistical evidence in the paper), nor the conclusion about whether the professor violated the criterion, are affected, skewed or tainted by the student's bias.

Answer choice (E): The student does not fail to distinguish between the professor's criterion and other objective criteria. Indeed, the student knows that what matters is the professor's criterion, and the student stays focused on that criterion in the argument. The error the student made was in misunderstanding the criterion, a flaw that was more accurately identified by answer choice C.
 gwlsathelp
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  • Joined: Jun 21, 2020
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#91990
Question type: flawed reasoning/argument, SN

Correct answer is C) "takes a condition that is among the requirements for a particular grade (necessary condition) to be a condition that is enough to guarantee that grade (sufficient condition)."

The teacher's criteria is, "gives A's only to papers whose conclusions were supported by reliable statistical evidence."
A :arrow: statistical evidence
The kid responds with, "the professor acknowledges that my conclusions were supported by reliable statistical evidence, but she gave my paper a B." There is no SN diagram to make here except to acknowledge that statistical evidence is occurs and that the A does not occur. He makes the mistake thinking that statistical evidence was sufficient for him to guarantee an A – if this were the case and he didn't get an A, then she would not be grading according to her criteria. However, the prof states the equivalent of "if you received an A, then you had statistical evidence". One can still have statistical evidence and receive a B as that does not negate or contradict the prof's grading criteria.

I selected A), but realize why C) is correct and selected it because I didn't quite understand what it was saying at the time and under pressure.
 Adam Tyson
PowerScore Staff
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#92376
Good work here spotting and understanding that the conditional reasoning was flawed, gwlsathelp . The great thing about this sort of situation is that while the correct answer may sound confusing because of its abstract nature, you can still select it with confidence because it is the only answer that addresses the language of conditionality! As long as you know you are looking at a conditional flaw (a Mistaken Reversal in this case - the student apparently thinks meeting a Necessary condition should guarantee meeting the Sufficient Condition), you can reject any answer that describes other types of flaws.

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