PrepTest 134, Section 2, Question 2
Psychologist: A study of 436 university students found(53 more words not shown)
The reasoning in the psychologist's(12 more words not shown)
- Apresumes, without providing(16 more words not shown)
- Bpresumes that all(7 more words not shown)
- Cfails to provide(8 more words not shown)
- Dfails to consider(15 more words not shown)
- Epresumes, without providing(20 more words not shown)
Reading the argument
If you can't sleep at night, wouldn't you be tired during the day?
That gives us an immediate alternative to the psychologist's story. The study connects daytime naps with insomnia. The psychologist thinks the naps cause the trouble sleeping. But people who already have trouble sleeping might take naps because they're exhausted. The same connection fits either direction.
The fishing workers supply another example of napping alongside insomnia. That doesn't settle which causes which. Seeing the two together in a second group still leaves us asking whether the nighttime sleep problem came first.
What we’re looking for
For the flaw question, I'd look for that overlooked possibility: insomnia might lead people to nap. We don't have to prove that this is what happens. It is enough that the evidence doesn't distinguish the psychologist's explanation from this reasonable alternative.
Working the answers
- A
The study compares students who nap with students who don't. It doesn't compare university students with the general population. The psychologist never needs to assume that students have more insomnia than everyone else to make the argument offered here.
- B
Saying that napping tends to cause insomnia doesn't say that every case of insomnia has that cause. The psychologist could accept several causes and still make this claim about napping. B criticizes a much stronger claim than the one in the conclusion.
- C
We can understand the ordinary meaning of napping well enough to follow the argument. The difficulty is deciding which way the relationship runs, not identifying a missing technical definition. Even with a precise definition of a short daytime sleep, the same causal question would remain.
- DCorrect
Perhaps the daytime naps are an effect of insomnia. Someone lies awake at night, becomes exhausted, and catches up on sleep during the day. That produces exactly the association the psychologist reports without establishing that the naps caused the insomnia. The psychologist needs a reason to rule out this direction before drawing the causal conclusion so confidently.
- E
The fishing workers are an example of people who nap and have insomnia. Whether someone in that occupation could have a regular sleep schedule doesn't resolve the causal direction. Even if regular schedules are possible, the workers observed could be napping because they cannot sleep at night.
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