CR - Inference

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CR - Inference

by visjain » Tue May 05, 2009 7:57 pm
A population study based on a 'Representative data sample', a sample just large enough to allow for decently accurate projections found that in 1975 there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60 to small towns and rural regions both within and across state boundaries. This finding turns out to have been in error. The problem was that people who had moved to Litivia from abroad were accidentally counted as part of interstate migration that year.

Which of the following can be inferred from the passage above?

a) Majority of people coming to Litivia from abroad were over the age of 60.

b) In 1975 fewer Litivia residents over the age of 60 changed residents than in any of the ten years prior to 1975.

c) People over the age of 60 who in 1975 came from abroad did not settle predominantly in small towns and rural areas.

d) The 'Representative data sample' for 1975 was too small to allow any meaningful predictions.

e) The 10 year trend mentioned in passage was due chiefly to moves over relatively short distances, mostly within the same state.

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Re: CR - Inference

by piyush_nitt » Tue May 05, 2009 9:22 pm
visjain wrote:A population study based on a 'Representative data sample', a sample just large enough to allow for decently accurate projections found that in 1975 there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60 to small towns and rural regions both within and across state boundaries. This finding turns out to have been in error. The problem was that people who had moved to Litivia from abroad were accidentally counted as part of interstate migration that year.

Which of the following can be inferred from the passage above?

a) Majority of people coming to Litivia from abroad were over the age of 60.

b) In 1975 fewer Litivia residents over the age of 60 changed residents than in any of the ten years prior to 1975.

c) People over the age of 60 who in 1975 came from abroad did not settle predominantly in small towns and rural areas.

d) The 'Representative data sample' for 1975 was too small to allow any meaningful predictions.

e) The 10 year trend mentioned in passage was due chiefly to moves over relatively short distances, mostly within the same state.
IMO A

Not really convinced but it looks best among lot.

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by nervesofsteel » Wed May 06, 2009 1:29 am
IMO B

if B is false then number of lativia residents were more than number 10 yrs ago.. and we cannot say the resukts were wron because other people migrated..
even though there was no immigration.. there the results shown by study would have been correct...

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by naveen.bobbili » Wed May 06, 2009 4:05 am
IMO A...Process of elimination.
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by hk » Wed May 06, 2009 9:32 am
I would go with A.

Reasoning: The study showed there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60. Now it also says that the result was incorrect because a lot of people who moved into Litivia were counted. Now if many were under 60 then the study's result would have been true as a drastic population over 60. But if the people who migrated from abroad were mostly over 60 then this would rise the total number of migrants and hence mislead the study.
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by vinaynp » Wed May 06, 2009 11:55 am
nervesofsteel wrote:IMO B

if B is false then number of lativia residents were more than number 10 yrs ago.. and we cannot say the resukts were wron because other people migrated..
even though there was no immigration.. there the results shown by study would have been correct...
I agree it is B

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Re: CR - Inference

by Objectivo » Wed May 06, 2009 12:06 pm
visjain wrote:A population study based on a 'Representative data sample', a sample just large enough to allow for decently accurate projections found that in 1975 there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60 to small towns and rural regions both within and across state boundaries. This finding turns out to have been in error. The problem was that people who had moved to Litivia from abroad were accidentally counted as part of interstate migration that year.

Which of the following can be inferred from the passage above?

a) Majority of people coming to Litivia from abroad were over the age of 60.

b) In 1975 fewer Litivia residents over the age of 60 changed residents than in any of the ten years prior to 1975.

c) People over the age of 60 who in 1975 came from abroad did not settle predominantly in small towns and rural areas.

d) The 'Representative data sample' for 1975 was too small to allow any meaningful predictions.

e) The 10 year trend mentioned in passage was due chiefly to moves over relatively short distances, mostly within the same state.
I'm not sure it's A or B.
The issue with A is that there's no indication of the balance between the number of minus-60 year old population vs the +60 years old population. Therefor, there's no way to know that the majority of foreign immigrants still couldn't have been under 60.

The issue with B seems to be that there's no way of knowing, since the wrongly cathegorised foreigners made the data unreliable. There still could have been an increase that was compensated by a relatively large number of +60 foreign immigrants.

The problem with C is that the issue is not the sample size, but wrongly cathegorised individuals.

The issue with D is that there's no way of knowing wether the moves were big or small (logic would seem to indicate the moves would be small, but that's just not something that can be derived from the text)

Conclusion: I'm mystified...

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by 2010gmat » Sat May 09, 2009 7:24 am
IMO C

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by sanp_l » Sat May 09, 2009 11:09 am
Even a minimum amount of travellers coming from abroad , being over the age of 60 might have been sufficient to make a trend reversal. hence A can't be.

Considering that after removing the outsiders the trend reversal doesnt hold true, it can be inferred that there certainly was some reversal. Then it can be said that B holds true.

C, D and E doesnt hold much to be the right one.

I go with B.
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by mehravikas » Sat May 09, 2009 6:53 pm
IMO - A

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by bmlaud » Sat May 09, 2009 11:36 pm
IMO B

Let’s say every year 100 people were migrating to small towns from Latvia. As per the survey, in 1975 the people migrated were less, say 80. But the number is considered wrong because lot of people from abroad who came to Latvia were counted as migrants. The people counted were the people coming into Latvia, but the whole argument is about people leaving for small towns . The two numbers should not be mixed. For any reason, even if the numbers are mixed the actual number should be greater than 100 (if the number of migrants has remained the same). But the number has actually decreased, this can happen only when fewer number of people are leaving for small towns from Latvia. Option B points out that correctly.
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by Jatinder » Sun May 10, 2009 1:37 am
IMO c

What's Oa?
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by thetrystero » Sun May 10, 2009 9:43 pm
A population study based on a 'Representative data sample', a sample just large enough to allow for decently accurate projections found that in 1975 there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60 to small towns and rural regions both within and across state boundaries. This finding turns out to have been in error. The problem was that people who had moved to Litivia from abroad were accidentally counted as part of interstate migration that year.

Which of the following can be inferred from the passage above?

a) Majority of people coming to Litivia from abroad were over the age of 60.

b) In 1975 fewer Litivia residents over the age of 60 changed residents than in any of the ten years prior to 1975.

c) People over the age of 60 who in 1975 came from abroad did not settle predominantly in small towns and rural areas.

d) The 'Representative data sample' for 1975 was too small to allow any meaningful predictions.

e) The 10 year trend mentioned in passage was due chiefly to moves over relatively short distances, mostly within the same state.
Situation:
1. 10-year trend in migration of residents over 60 to countryside inter and intra state was bucked in 1975.
2. This was later found to be in error because foreign immigrants to Litivia were included in the interstate count.

the reversal here is that dramatically fewer residents moved to the countryside in 1975 vs 10 years prior. If the immigrants were counted as outflow from countryside to city, this could explain the sudden exodus numbers

A. proportion between foreigners <60 and foreigners >60 is irrelevant. what matters is proportion of >60 foreigners wrt >60 citizens.
B. data was adulterated, so we can't tell
C. keep
D. problem says it was decent enough. always give it the benefit of the doubt.
E. we only know that the trend was for inter/intra state movement in composite. nowhere does it tell is what the proportion of each was.

If more foreigners settled in the country than in the city, this data would support a following of the trend but if instead more of them settled in the city, this would give the impression of mass migration from country to the city.

My answer: C

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Re: CR - Inference

by thetrystero » Sun May 10, 2009 9:50 pm
visjain wrote:A population study based on a 'Representative data sample', a sample just large enough to allow for decently accurate projections found that in 1975 there had been a dramatic reversal of a 10 year tendency toward migration of Litivia residents older than 60 to small towns and rural regions both within and across state boundaries. This finding turns out to have been in error. The problem was that people who had moved to Litivia from abroad were accidentally counted as part of interstate migration that year.

Which of the following can be inferred from the passage above?

a) Majority of people coming to Litivia from abroad were over the age of 60.

b) In 1975 fewer Litivia residents over the age of 60 changed residents than in any of the ten years prior to 1975.

c) People over the age of 60 who in 1975 came from abroad did not settle predominantly in small towns and rural areas.

d) The 'Representative data sample' for 1975 was too small to allow any meaningful predictions.

e) The 10 year trend mentioned in passage was due chiefly to moves over relatively short distances, mostly within the same state.
@visjain: OA please. What was the source?

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CR - Inference Question

by visjain » Thu May 14, 2009 11:04 am
OA Given is (E). I am also trying to analyze it. Here are my thoughts.

1) Look at the following things in passage carefully
a) dramatic reversal of trend -->
It does not mean people did not migrate at all. They might have migrated to small towns and rural regions only within the state boundaries or to small towns and rural regions only outside the state boundaries [Interstate migration].
b) People who moved from abroad were counted as part of Interstate migration only and not as part of within the state migration.
c) Thus we can infer that the 10 year tendency was only towards within the state migration.