#9 - Cereal advertisement: Fitness experts say that regu

[Administrator]

Complete Question Explanation

Conditional and causal reasoning combine in this stimulus, a combination that can confuse an unwary test taker. When that happens, the conclusion is typically causal, and that's where we should typically focus our efforts. This question follows that typical pattern.

First, we are given a causal claim, that exercise causes fitness ("is the most effective way to become physically fit"). No problems there - because this is a premise, we accept it at face value.

Next, we are given a conditional claim using a variant of the "people who" sufficient condition indicator, "adults who". We learn that eating cereal daily is sufficient to show more regular exercise. That conditional relationship is another way of showing that the two conditions have a positive correlation. At this point we would do well to remember that correlation never proves causation, and that false assumption is where many causal arguments go wrong one way or another.

Finally, a conclusion tells us that eating cereal daily will apparently lead to greater fitness. The author has presumed that eating cereal actually causes one to exercise more, when in fact there may be no causal connection between the two correlated conditions. Our prephrase for this Flaw in the Reasoning question should be to point out that mistaken assumption about a correlation indicating a causal relationship.

Answer A: This is the correct answer. It describes exactly what we prephrased, an assumption of causation from a mere correlation.

Answer B: Bringing up new information (nutrition) is the wrong way to attack a Flaw question, as it is in the same category as Must Be True questions and the correct answer should rely solely on the information in the stimulus. Since nutrition was not an issue raised in the stimulus, it should not be part of our credited answer.

Answer C: This one looks attractive, if you squint at it in dim light. It talks about making a bad inference, which the author did do, but it hinges on making the same bad assumption that the author made, that eating cereal is, in fact, a cause of exercise and thus fitness. Instead of pointing out that flaw, this answer relies on that flaw and instead points to a problem that did not happen in the stimulus,namely assuming that eating cereal is the sole cause of exercise. Since our author did not appear to make that assumption, this one is a loser.

Answer D: This answer choice would apply to a study or survey problem, and while studies were involved here there is no reason to believe that we have an unrepresentative sample of any kind. Stay focused on the causal flaw and this one won't draw you in, but without a good prephrase it might be tempting. Be sure to note the causal claim and don't be distracted.

Answer E: There is no "whole to part" element to this argument (what we call an Error of Division). At no point did our author claim or assume that a group has a characteristic and that an individual in the group must therefore have it. Again, a solid prephrase about causal reasoning and correlation should save you from picking this loser.

[ntlsat]

I just wanted to add a diagram to this explanation, which helped me to better understand and conceptualize the validity of answer choice (A).

Eating cereal is correlated with regular exercise

Exercise causes physical fitness.

Eating cereal --> regular exercise --> physical fitness.

The first arrow is one of correlation; the second is one of [causation].

The conclusion then says that eating cereal causes physical fitness, but in fact it's just correlated.

I don't know if this helps anyone, but it worked for me!

[Adam Tyson]

Thanks, ntlsat! Your analysis is correct, although we would recommend not using the same diagramming tool to mean two different things (an arrow for correlation and a second, identical arrow for causation). In fact, in our methodology we reserve the arrow for conditional, rather than causal, arguments. We rarely diagram causal relationships, but when we do we usually just label them with C (for cause) and E (for effect). However, whatever works for you, use it!

[Kennedv_]

Hi there,

Could you show what (C) looks like?

I am seeing it as: "infers that a given factor (eating cereal) is the sole predictor of a result (physically fit) merely on the grounds that the factor (eating cereal) has been shown to contribute to that result (physically fit)."

But wait is it wrong because the grounds (the conditional claim) told us that if you eat cereal then you exercise more and not become physically fit?

Thanks in advance

[Jeremy Press]

Hi Kennedv_,

There are at least two problems with answer choice C, the first being the word "sole." Although the conclusion can be interpreted to state that eating cereal is one predictor of physical fitness, it doesn't call it the "sole," or the "only," predictor of physical fitness.

The second problem with answer choice C is the one you correctly identify. The "grounds" (i.e. the premises) only state that there is a correlation between eating cereal and exercising regularly ("adults who eat cereal every day exercise more regularly than adults who do not eat cereal"). But the premises don't state that cereal definitely causally contributes to physical fitness. Note that just based on that correlation statement, we cannot even infer that eating cereal causally contributes to exercising regularly. The correlation might just be coincidental.

I hope this helps!

Jeremy