Statistics CR Flaw

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Statistics CR Flaw

by sachindia » Fri Aug 24, 2012 10:25 pm
Demographers doing research for an international economics newsletter claim that the average per capita income
in the country of Kuptala is substantially lower than that in the country of Bahlton. They also claim, however, that
whereas poverty is relatively rare in Kuptala, over half the population of Bahlton lives in extreme poverty. At least
one of the demographers' claims must, therefore, be wrong. The argument above is most vulnerable to
which of the following criticisms?
A. It rejects an empirical claim about the average per capita incomes in the two countries without making any
attempt to discredit that claim by offering additional economic evidence.
B. It treats the vague term "poverty" as though it had a precise and universally accepted meaning.
C. It overlooks the possibility that the number of people in the two countries who live in poverty could be the same
even though the percentages of the two populations that live in poverty differ markedly.
D. It fails to show that wealth and poverty have the same social significance in Kuptala as in Bahlton.
E. It does not consider the possibility that incomes in Kuptala, unlike those in Bahlton, might all be very close to the
country's average per capita income.

Ans is E
but why not C?
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by mohan514 » Sat Aug 25, 2012 9:16 am
i completely missed this question..

looks like a tough one to me but b,c and e all of them look convincing to me..


experts should help us out

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by everything's eventual » Mon Aug 27, 2012 8:59 pm
Hello, I do not usually use rules per se to solve CR questions. I use my understanding of the question. So I will not be able to explain using rules and regulations.This is how I did it :

The passage says that though half the population in Bahlton lives in extreme poverty, its GDP is more than that of Kuptala. The argument is that because of this paradox,one of the demographers' claims is wrong.

But is it possible for half the country's population to be extremely poor and still have a good GDP? Yes of course - If half of the country has an income much lower than the GDP but the other half is extremely extremely rich then the overall GDP of the country can be higher than the GDP of a country where most people's income is close to the GDP. It is possible right?

Options A, B and D are out of scope. Option E fits my explanation perfectly.

So I chose E.

Hope my understanding is correct.

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by vk_vinayak » Mon Aug 27, 2012 9:19 pm
C. It overlooks the possibility that the number of people in the two countries who live in poverty could be the same even though the percentages of the two populations that live in poverty differ markedly.
D. It fails to show that wealth and poverty have the same social significance in Kuptala as in Bahlton.
E. It does not consider the possibility that incomes in Kuptala, unlike those in Bahlton, might all be very close to the country's average per capita income.

Ans is E
but why not C?
Lets say 10% of population in Kuptala lives under poverty, and the figure for Bahlton is 60%. It is very possible that remaining 40% of the people in Bahlton are extremely rich (eg: Each person may be a multi-billionaire). In that case both claims hold good.

E is the best answer.
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by sachindia » Tue Aug 28, 2012 6:03 am
Say 100 people in kuptala are poor. population of kuptala=1000 (10% poor)
and
100 people in bahlton are poor. population ofbahlton =200(50% poor)

and as vinayak said, other 100 in bahlton might be very rich.. so both demographer's claims are correct.

so C is also correct.

Can somebody explain me why C is wrong?
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by everything's eventual » Tue Aug 28, 2012 5:44 pm
Yes....as you said you have 100 people poor in both the countries now. However, the answer to this CR question needs to show that the 900 remaining people in Kuptala have an income closer to GDP where as income of the 100 remaining people in Bahlton could be much higher than the GDP. Here the rich people are the deciding factor ( not the poor people). So even if Option C states that number of poor people in both countries could be same, it fails to provide any information regarding the people above the poverty line.

Option E provides this info and so I chose E.

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by sachindia » Tue Aug 28, 2012 7:41 pm
amazing.. thanks!!
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by ankit0411 » Tue Aug 28, 2012 10:30 pm
sachindia wrote:Demographers doing research for an international economics newsletter claim that the average per capita income in the country of Kuptala is substantially lower than that in the country of Bahlton. They also claim, however, that whereas poverty is relatively rare in Kuptala, over half the population of Bahlton lives in extreme poverty. At least one of the demographers' claims must, therefore, be wrong. The argument above is most vulnerable to which of the following criticisms?
A. It rejects an empirical claim about the average per capita incomes in the two countries without making any attempt to discredit that claim by offering additional economic evidence.
B. It treats the vague term "poverty" as though it had a precise and universally accepted meaning.
C. It overlooks the possibility that the number of people in the two countries who live in poverty could be the same even though the percentages of the two populations that live in poverty differ markedly.
D. It fails to show that wealth and poverty have the same social significance in Kuptala as in Bahlton.
E. It does not consider the possibility that incomes in Kuptala, unlike those in Bahlton, might all be very close to the country's average per capita income.

Ans is E
but why not C?
the argument says that :

Kuptala - Average capita income - 90/100 = 0.9
Bahlton - Average capita income - 100/50 =2

Half the population is in poverty for Bahlton i.e atleast 25 people are in poverty that means if the average is 2 then then the incomes might be at extreme levels( many people might have less than 2 and many of them greater than 2 )

Whereas in Kuptala, poverty is rare because majority of them have an income closer the to average (.9).

Since we are dealing with average per capita income we can rule out option C, which talks about the number of people in poverty.

Hence E

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by mparakala » Tue Jan 29, 2013 8:02 pm
the best way to answer the poverty difference and the avg per capita income diff is by choosing option E

In Bahlton, there are people who are too rich and people who are too poor.

so, this answers why poverty as well as avg PCI are greater in Bahlton when compared to Kuptala.

E

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by ceilidh.erickson » Wed Jan 30, 2013 11:04 am
Any time you see DIFFERENCES IN STATISTICS/METRICS/MEASUREMENTS on CR questions, there is a logical flaw - the author is assuming that those metrics convey the same information. In this case, per capita income and rate of poverty are two different statistics that the author is treating as the same.

Per capita income is the average of all incomes (the entire population) in a given country, but it does not take into account standard deviation - how far the data points lie from that average.

Rate of poverty, on the other hand, is not a metric of the entire population, but only of a certain percentage at the bottom of the economic ladder. If the rate of poverty is low, it must be true that most people make close to the average per capita income; i.e. there is a low standard deviation. If there is a high rate of poverty but also a high per capita income, it must be true that there is a high standard deviation - many people are very rich, and many others very poor, giving us an average in the middle.

A. It doesn't necessarily reject the "per capita" claim; it just says ONE of the claims must be wrong.
B. This is a valid criticism, but a minor one. Regardless of how precisely we define "poverty," it's still a metric of one segment of the population, while "per capita" is the population as a whole.
C. This falls prey to another change in statistic. NUMBER of people is irrelevant here. Both of the metrics we're looking at - "per capita" and "poverty" - are proportional (percent-based) metrics. We don't care about total numbers.
D. Social significance is irrelevant. We don't care if the people in those countries care! We just care whether the data is true.
E. This speaks to the difference in STANDARD DEVIATION. Correct!
Ceilidh Erickson
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Harvard Graduate School of Education