Two great questions arghya. Thanks for bringing them in. Lots of different answers circulating around, so I thought I'd go through them with method and see where we end up. The answers, as far as I can tell, should be D for the politician question and A for the medical question.
The first question, with the politician, is a weaken question. With these, it's important to look as closely as possible at the premises and the conclusion. Make sure you don't change the words as they're written to fix a bad argument. Often, the arguments made in CR passages are so terrible that, in taking notes, you end up making them better. Don't do it!
Politician: From the time our party took office almost four years ago the number of people unemployed city-wide increased by less than 20 percent. The opposition party controlled city government during the four preceding years, and the number of unemployed city residents rose by over 20 percent. Thus, due to our leadership, fewer people now find themselves among the ranks of the unemployed, whatever the opposition may claim.
Conclusion: Fewer people are unemployed because of party
Premise: Our party saw unemployment increase by less than 20%, other party by more than 20%
At first glance, this may look like a typical "percent isn't the same as number" kind of question. But look closely at the conclusion. The party is saying fewer people are unemployed, when they admit that there was an INCREASE in unemployment! Just because it was less than 20% doesn't make it a decrease. In reality, the fact cited totally undermines that conclusion.
The reasoning in the politician’s argument is most vulnerable to the criticism that
(A) the claims made by the opposition are simply dismissed without being specified
Problem: This argument has nothing to do with what the opposition did or didn't do. In fact, all that stuff about opposition is a big red herring. All we care about is whether or not there are "fewer people" unemployed now than before the party took power.
(B) no evidence has been offered to show that any decline in unemployment over the past four years was uniform throughout all areas of the city
Problem: Unemployment density is immaterial; we just need the overall number.
(C) the issue of how much unemployment in the city is affected by seasonal fluctuations is ignored
Problem: This doesn't address the data we've been given, and is irrelevant.
(D) the evidence cited in support of the conclusion actually provides more support for the denial of the conclusion
Answer: Yep. If unemployment INCREASED, even by 2%, that would lead one to the conclusion that MORE people are unemployed, not fewer.
(E) the possibility has not been addressed that any increase in the number of people employed is due to programs supported by the opposition party
Problem: This is tempting, because it makes it sound like the opposition might have had some effect on a later increase in employment. However, there was no increase! There was only a decrease of "less than 20%".
Medical research findings are customarily not made public prior to their publication in a medical journal that has had them reviewed by a panel of experts in a process called peer review. It is claimed that this practice delays public access to potentially beneficial information that, in extreme instances, could save lives. Yet prepublication peer review is the only way to prevent erroneous and therefore potentially harmful information from reaching a public that is ill equipped to evaluate medical claims on its own. Therefore, waiting until a medical journal has published the research findings that have passed peer review is the price that must be paid to protect the public from making decisions based on possibly substandard research.
This is an assumption question, so we need to look at the conclusion and premises once again.
Conclusion: Medical journal peer review is only way people can avoid bad research.
Premises: Research subject to peer review before publication in journals, to be sure false research doesn't get out
(A) unless medical research findings are brought to peer review by a medical journal, peer review will not occur
ANSWER: When in doubt about the correct answer on an assumption question, try the NOT test. Take the opposite of this answer choice. "Peer Review can occur without being brought to peer review by a medical journal" [my paraphrase]. Uh-oh. Now we don't need to get peer review from a journal, so the journal itself is not the only way to protect the public.
(B) anyone who does not serve on medical review panel does not have the necessary knowledge and expertise to evaluate medical research finding
PROBLEM: This is tempting because the passage says something close to it. But we don't care if SOME people have the expertise outside of the panel itself. It's enough to know that some people don't. I can see that A LOT of you liked this answer choice. Be wary of picking something because the passage says something close to it. The passage says that SOME people don't have the necessary knowledge to evaluate research, not ALL of them. The "anyone" here goes WAY too far.
(C) the general public does not have access to the medical journals in which research findings are published
PROBLEM: Once the journals are released, the info has been peer reviewed. In reality, we NEED the public to have access to the journals.
(D) all medical research findings are subjected to prepublication peer review
PROBLEM: "All" is always a dangerous word, so be careful of it. Let's try the not test: "All medical research findings are NOT subjected to prepublication peer review." But couldn't that be because they aren't published at all? We don't need ALL medical research findings to get the review, just the stuff that might get out to the public.
(E) peer review panels are sometimes subject to political and professional pressures that can make their judgments less than impartial
PROBLEM: This hurts our argument, because we want people on the peer review panels to be protecting the public.
Hope that helps!
Tommy Wallach | Manhattan GMAT Instructor | San Francisco
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