princeton CR

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princeton CR

by bblast » Wed May 18, 2011 10:38 am
In 1987, an environmental action group reported a 65-percent response rate to a questionnaire sent to all of its members. The subject of the questionnaire was ocean dumping. On the basis of these results, the group expects a 65-to-70 percent response rate to its upcoming questionnaire on air pollution.
The environmental group's expectation is based on which of the following assumptions?

The group's membership has not declined by more than 5 percent since 1987.

The same number of surveys will be distributed as were distributed in 1987.

People who are concerned about ocean dumping are even more concerned about air pollution.

The response rate of one questionnaire can be predicted from that of another.

The total amount of pollution today is the same as it was in 1987.

imo- c
oa-d
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by mundasingh123 » Wed May 18, 2011 12:19 pm
bblast wrote:In 1987, an environmental action group reported a 65-percent response rate to a questionnaire sent to all of its members. The subject of the questionnaire was ocean dumping. On the basis of these results, the group expects a 65-to-70 percent response rate to its upcoming questionnaire on air pollution.
The environmental group's expectation is based on which of the following assumptions?

The group's membership has not declined by more than 5 percent since 1987.

The same number of surveys will be distributed as were distributed in 1987.
On the other hand D is a necessary assumption

People who are concerned about ocean dumping are even more concerned about air pollution.

The response rate of one questionnaire can be predicted from that of another.

The total amount of pollution today is the same as it was in 1987.

imo- c
oa-d
I eliminated C because the stimulus takes a survey that took place in 1987 as a benchmark . WE dont what know what year is the current survey taking place in . It could be 2011 as well . People who responded to the survey in 1987 may not remain subscribers any more
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by atulmangal » Wed May 18, 2011 8:22 pm
Hi, IMO D

See, the Op C is tricky but still there is a flaw.

Premise 1:

an environmental action group reported a 65-percent response rate to a questionnaire sent to all of its members.

Expectation:

Now the expected response is 65-70, means even if the response is 65% no problem. That means if the no of people are concerned even at the same level 65% same as earlier is available. Op C says (see below) more concerned thing but we don't need that more concerned thing. There are others flaws too but i think this one is sufficient.

Op C

People who are concerned about ocean dumping are even more concerned about air pollution.

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by assetgmat » Wed May 18, 2011 10:12 pm
I think it is C indeed.
Negate the assumption.
If People who are concerned about ocean dumping are NOT even more concerned about air pollution.
then, why would the response be better than before.

Negate D:
The response rate of one questionnaire can NOT be predicted from that of another.
Will that help in answering why the response will be more or less. NO

So, C

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by gmat11 » Wed May 18, 2011 11:14 pm
I think it is C indeed.
Negate the assumption.
If People who are concerned about ocean dumping are NOT even more concerned about air pollution.
then, why would the response be better than before.

Negate D:
The response rate of one questionnaire can NOT be predicted from that of another.
Will that help in answering why the response will be more or less. NO

So, C

Asset
IMO the answer is D
C is wrong because responding to something does not warrant concern. Even if a person is concerned, he/she may not respond to a questionare beacuse of number of other reasons.

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by Geva@EconomistGMAT » Thu May 19, 2011 1:26 am
assetgmat wrote:I think it is C indeed.
Negate the assumption.
If People who are concerned about ocean dumping are NOT even more concerned about air pollution.
then, why would the response be better than before.

Negate D:
The response rate of one questionnaire can NOT be predicted from that of another.
Will that help in answering why the response will be more or less. NO

So, C



Asset
1) The negation technique works thus: if the reverse of the answer choice weakens the conclusion, then the answer choice itself is a necessary assumption without which the conclusion cannot be reached. Negating C does not by itself weaken the conclusion: if the people are not even more concerned with pollution, this still allows the possibility of the people being AS concerned with pollution as they were with dumping, in which case we'll get the same 65 percent allowed by the conclusion. You need a stronger weakening reaction to choose an answer choice based on a negation technique.

2) The key is to come up with your own prediction of what the right answer choice should do, and stick to it. When reaching the conclusion that the pollution survey will also have 65-70%, the author is assuming one thing only - that the group as a whole will be as willing (perhaps slightly more) to answer this survey as it was to answer that survey. We don't know WHY - perhaps they care about the topics, perhaps they just like answering surveys. We certainly DON'T know that the people answering both surveys will be the same people, which is the added, unnecessary assumption that C adds (and why c is wrong). We just know that in order to make that conclusion, we must assume that the past response to the survey somehow, in some nebulous, unknown way, can be used to predict the response to this survey.

Tell yourself this, and then look at the answer choices for one that says the same thing in different words, and D will be the only viable answer.
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