Q25 - Therapist: In a recent study

[joyce.hau]

I understood that this argument is flawed because it deduces a condition true for "most" people out of a sample that is not necessarily representative. But then I had trouble seeing how B could be the correct answer. How does that even factor into the argument? I'd picked D because it seemed to attack the weak link between the sample and "most" people in the population.

Please help! Thank you so much!!

[ManhattanPrepLSAT1]

I think I would phrase the flaw a bit differently. Notice that we have a "large, diverse sample."

The evidence states that 75% of 60 problems cleared up after therapy.

The argument concludes that most people will have their problems cleared up after therapy.

75% of 60 is 45. That leaves 15 problems that don't clear up after therapy. What if those 15 problems are the ones that afflict most people? If that were true, the argument would fall apart! Thus, the argument overlooks this possibility, making B correct.

Another way of thinking about this: Consider the relationship between the two "most" statements. The evidence tells us that most of the 60 problems were cleared up with therapy. The conclusion is that most people will have their problem cleared up by therapy. That assumes that most people have those particular problems.

(A) is not taken for granted in the argument. It never says that there are no unresolvable problems, which is what this answer choice is implying.
(B) correctly states the flaw for the reasons above.
(C) is not taken for granted in the argument. The argument's conclusion is consistent with the possibility that some people have more than one problem to be addressed by therapy.
(D) is off topic. The argument only addressed behavioral therapy, not other forms of therapy.
(E) is not taken for granted. The argument is about people who have psychological problems and wrests on assumption of the distribution of those problems across people who have such problems. However, the likelihood that someone from the general public would have psychological problems is never at issue.

#officialexplanation

[erho]

Hi, where in the argument does it account for the fact that some may suffer from more than one problem (answer choice c)?

[matthewyoung2008]

it doesn't account for the fact that some may suffer from more than one problem, and it isn't necessary to do

the key in this problem is recognizing that the 60 different psych problems each has a particular prevalence rate

if the 75% consisted of problems that were not prevalent, while the remaining 25% consisted of problems that were hugely prevalent, then you cannot say that the 50-week treatment is "all that most people need" because if the remaining 25% for whom problems did not clear up consisted of problems that were hugely prevalent, then the treatment is NOT what most people need -- instead, most people need something else

[shirando21]

I think I would phrase the flaw a bit differently. Notice that we have a "large, diverse sample."

The evidence states that 75% of the problems cleared up after therapy.

The argument concludes that most people will have their problems cleared up after therapy.

The flaw is that the argument fails to consider the distribution of those problems that would be cleared up by therapy. Suppose that those problems that are cleared up by therapy are rare in the population, whereas the problems that would not be cleared up may be very common. Stated this way, answer choice (B) makes a lot of sense. It says that the argument failed to consider that a potentially unresolvable problem may afflict most people. In which case, the conclusion would not follow.

(A) is not taken for granted in the argument. It never says that there are no unresolvable problems, which is what this answer choice is implying.
(B) correctly states the flaw for the reasons above.
(C) is not taken for granted in the argument. The argument's conclusion is consistent with the possibility that some people have more than one problem to be addressed by therapy.
(D) is off topic. The argument only addressed behavioral therapy, not other forms of therapy.
(E) is not taken for granted. The argument is about people who have psychological problems and wrests on assumption of the distribution of those problems across people who have such problems. However, the likelihood that someone from the general public would have psychological problems is never at issue.

60 problems * 75%=45 problems can be cleared up within 50 weeks of the therapy. but you don't know how many people suffer from the 45 problems which can be cleared up within 50 weeks, how many people suffer from the other 15 problems, which may not be cleared up within 50 weeks. If there are lots more people suffer from the 15 problems, then the conclusion is over-generalization.
that's what makes B correct.
I understood the flaw, but did not feel B expressed it at first glance...

[eapetrilli]

This question has one of the most vague conclusions I have seen on the LSAT, and makes us take a logical leap as to the refferent. The conclusion can refer to the 60 problems or to all psychological problems, and since this is a flaw question, it makes sense to try to go after that ambiguity. After not finding any answer choices that addresses a flaw that would exist in that second interpretation of this fishy conclusion, I had already spent way too much time trying to untangle the stimulus and had thusly wrecked my performance on the last page of questions. I guess sometimes the LSAT just coaxes you into a trapdoor

[Joetrot88]

Listen if you didn't notice there is a difference between PEOPLE and PROBLEMS the first time you read it.. keep that in mind and read again.

60 PROBLEMS were studied on a DIVERSE SAMPLE (DOESN'T TELL US HOW MANY PEOPLE JUST THE # OF PROBLEMS).. okay that can mean that 59 of them only affected one person. Therefore, if the problems cleared up withing 50 weeks we can't conclude this is adequate for MOST PEOPLE.

If they gave us a number of persons in the study rather than problems then this would make sense. However, it doesn't and answer choice B is correct.

[wj097]

(E) is not taken for granted. The argument is about people who have psychological problems and wrests on assumption of the distribution of those problems across people who have such problems. However, the likelihood that someone from the general public would have psychological problems is never at issue.

On a separate issue, I still read that the sample in the stimulus is representation of the general public, rather than those who have psychological problems. Reason being:
- It says "large, diverse sample of ppl"
- Concludes about most ppl

If those sample in the premise did not match the ppl in the conclusion in terms of representative scope, then I think we are facing with unrepresentative sample issue, which makes (E) a likely answer choice...please let me know if anyone thinks otherwise

[shkim121]

I have been obsessed with the question for almost a day.

Now I feel I nailed it. Please correct me if I am wrong.

P: 75% of problems are fixed within 50weeks of therapy
C: 50weeks of therapy is all that needed for most people

There is a term shift from problems to people.
For this argument to work, we need to assume that all the problems most people suffer fall within the 75% category.

At first, I had hard time rationalizing how (B) can be the answer.
Then I paraphrased a little bit.

"fails to address the possibility that "each and every" one of the
60 problems might afflict all~~"

Then it dawned on me that if all of the 60 problems affect most
people, we can't say 50weeks is all that needed.

[ManhattanPrepLSAT1]

Nice work shkim121!

Here's how I look at it... Suppose there are 1000 people with psychological problems. Amongst those 1000 people 60 different psychological problems have been identified. Lets suppose some of them are rare and some of them are common. For our illustration, lets assume that 59 of those problem affect only 1 person each. The remaining 941 people all suffer from the same remaining psychological problem.

Well what happens if the rare ones are easier to cure? And the most common psychological problem is impossible to cure. Then, we could 75% of the problems alleviated, but not 75% of the people with their problem alleviated.

Hope that helps!

[timsportschuetz]

As in many flaw questions, a weak conclusion is stated. "Weak" in a sense that the conclusion is not categorical! Notice how the conclusion simply states that 50 weeks of sessions is all that MOST people need. This is extremely useful to test makers since they can utilize the weak conclusion to trap test takers. Once I noticed this exact pattern, it repeats at least 2 to 3 times on EVERY LSAT (I would say, that this is one of the most common scenarios in FLAW questions). Answer (A) states that the therapist takes for granted that there are NO problems that take longer to remedy than the 60 problems studied (so, longer than 50 weeks). However, notice how the conclusion allows for this exact fact to happen by being very 'weak' in its' language. If you negated (A) and told the therapist that SOME psychological problems take longer than 50 weeks to clear up, the therapist would simply say: "Ok, this may be true, but I specifically said that MOST people would have their problems cleared up in the 50-week timespan." Hence, (A) would NOT impact the argument at all.

LOOK FOR WEAK CONCLUSIONS ON FLAW QUESTIONS AND I GUARANTEE THAT YOU WILL BE ABLE TO ELIMINATE ANSWERS THAT YOU PREVIOUSLY FOUND ATTRACTIVE MUCH MUCH FASTER!

Take a look at these questions to illustrate the above:
PT 39 Section 4 #20
PT 37 Section 4 #17
PT 53 Section 1 #18
PT 54 Section 4 #16
PT 47 Section 1 #23

[coco.wu1993]

I did this one right, but I still have problem with B. Even if any given one of the 60 problems studied does not afflict most people, people afflicting the 60 problems in total can account for the majority of the population, so the conclusion still holds. Any thought?

[christine.defenbaugh]

I did this one right, but I still have problem with B. Even if any given one of the 60 problems studied does not afflict most people, people afflicting the 60 problems in total can account for the majority of the population, so the conclusion still holds. Any thought?

Thanks for the question, coco.wu1993!

I'm a little confused by exactly what you're asking, but I think there might be two different things that could be tripping you up here.

First, you are looking at what happens to the argument if any one of the problems does NOT afflict most people - that sounds like you are negating this answer choice. But the answer choice is written in "fails to address the possibility that" syntax.

When a flaw answer is written as "fails to address the possibility that", we do NOT want to negate it! Consider the classic example:

PREMISE: All boys like sports
CONCLUSION: Andy likes sports

This argument is flawed because it fails to consider the possibility that Andy might not be a boy. If we were to negate that, we'd have "Andy is a boy", and that would make the argument work! The thing that the argument fails to consider is whatever thing could potentially destroy it.

In general, it's useful to think of flaw syntax in these two ways:

1) The argument is flawed because it takes for granted that [the assumption], and
2) The argument is flawed because it fails to consider the possibility that [the assumption might not be true]

So, in this case, the argument-destroyer is the idea that one of the psychological problems (perhaps one that doesn't get cleared in 50 weeks of therapy) might affect most people.

The second thing that may be causing some issue for you is the idea that the thing that destroys the argument may not make the conclusion definitively false, just unsupported.

To return to the Andy argument, if Andy is NOT a boy, it may still be possible that girl-Andy does indeed like sports. However, Andy being a girl still destroys the argument, as it is no longer reasonable to conclude that she likes sports on the basis of a rule that all BOYS like sports. In other words, the negated assumption destroys the connection between the premise and the conclusion, rather than necessarily making the conclusion provably false.


Do either of these ideas help clear up the issue?

[andrewgong01]

I think I would phrase the flaw a bit differently. Notice that we have a "large, diverse sample."

The evidence states that 75% of the problems cleared up after therapy.

The argument concludes that most people will have their problems cleared up after therapy.

The flaw is that the argument fails to consider the distribution of those problems that would be cleared up by therapy. Suppose that those problems that are cleared up by therapy are rare in the population, whereas the problems that would not be cleared up may be very common. Stated this way, answer choice (B) makes a lot of sense. It says that the argument failed to consider that a potentially unresolvable problem may afflict most people. In which case, the conclusion would not follow.

(A) is not taken for granted in the argument. It never says that there are no unresolvable problems, which is what this answer choice is implying.
(B) correctly states the flaw for the reasons above.
(C) is not taken for granted in the argument. The argument's conclusion is consistent with the possibility that some people have more than one problem to be addressed by therapy.
(D) is off topic. The argument only addressed behavioral therapy, not other forms of therapy.
(E) is not taken for granted. The argument is about people who have psychological problems and wrests on assumption of the distribution of those problems across people who have such problems. However, the likelihood that someone from the general public would have psychological problems is never at issue.

If we have a large diverse sample then our sample should be a pretty good sample of the true population distribution of illnesses. If this is the case, doesn't that basically rule out B, the correct answer choice, because "B" is saying we may not have a fair representation of the distribution in the true population? Or am I incorrectly understanding they meant by "diverse sample of people" where they actaully meant they went out and found like 1 person for each of the 60 problems?

[ohthatpatrick]

We have a large, diverse sample -- great starting point for medical science.

They kept track of 60 different conditions (all the way from depression and anxiety to Pirate's Disease and Self-Knighting).

75% of those conditions .... 45 of the 60 ... cleared up over 50 weeks.

So most people, the author thinks, only need the 50 weeks.

The flaw in this argument is that we care less about what percentage OF THE CONDITIONS were cured.

We care more about what percentage OF THE PEOPLE were cured.

Suppose that the 45 conditions that cleared up were the real obscure ones, like Pirate's Disease, that only afflict 1% of the population.

Meanwhile, the 15 conditions that DIDN'T clear up in 50 weeks were things like depression, anxiety, stress ... stuff that afflicts more than 50% of the population.

(B) is getting at the disconnect between saying "most conditions are cured within 50 weeks" and saying "most people would be cured within 50 weeks".

If most people have a condition that DOESN'T clear up in 50 weeks, then they would still need more than 50 weeks of behavioral therapy.

[LukeM22]

Sorry, what is wrong with Answer C again?

I understand B, but would the scenario posited in C refute the idea that 50 weeks is enough? If I had disease X, began treatment, and during the 50 week recovery week contracted disease Y, wouldn't that prolong the recovery process beyond 50 weeks and also refute the same idea?

Thank you,

[ohthatpatrick]

(C) accuses the author of making a certain Necessary Assumption.

Does the author have to assume that ZERO people in the study had more than one condition?

If we negated that, we would know that
"at least one person in the study had at least two conditions".

Does that represent a powerful weaken idea?


Since it does not, we can't say that the author "needs to assume that ZERO people have more than one condition".

The author needs to assume that "if patients had more than one condition, usually all their conditions cleared up".

One of the quickest / easiest hacks on Flaw is to beware of extreme assumption answers:
"takes for granted / presumes / fails to establish" + [some extreme idea]

There are tons of wrong answers written in this fashion.

Hope this helps.