Evaluate

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Evaluate

by heshamelaziry » Sat Oct 24, 2009 5:13 pm
For every 100 automobile drivers who are involved in a collision due to brake failure, 1 will be seriously injured. A new safety feature exists that is nearly 100 percent successful in preventing collisions due to brake failure. Because the risk of serious injury from malfunction of the new safety feature is one out of 10,000, it is clearly safer for automobile drivers to have this new safety feature installed than not.

Which of the following would it be most helpful to know in order to evaluate the argument?

The probability that an automobile driver will be involved in a collision due to brake failure

The probability that an automobile driver will be involved in any sort of collision

The number of automobile collisions that occur for reasons other than brake failure

The number of new safety features being released that prevent other types of collisions

The total number of automobile drivers that have had this new safety feature installed


OA A I don't see how the answer provides any new information ?

OE[spoiler]This is an evaluation question. If the risk of getting into these collisions due to brake failure is very small and only 1 out of 100 of that small number is seriously injured, it might be safer not to install the new safety feature.


[/spoiler] HOw does this makes sense ?

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by gmatv09 » Sat Oct 24, 2009 6:11 pm
solved by PoE

The probability that an automobile driver will be involved in a collision due to brake failure

This choice talks about brake failure and collisions .. Hence possible answer

The probability that an automobile driver will be involved in any sort of collision

This one talks about any sort of collision... It is more generic.

The number of automobile collisions that occur for reasons other than brake failure

Doesn't talk about collisions due to brake failures

The number of new safety features being released that prevent other types of collisions

Safety features which prevent other types (not brake failures)

The total number of automobile drivers that have had this new safety feature installed

It doesn't matter how many drivers have installed ... We need to find the effectiveness of the soln.

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by Testluv » Sat Oct 24, 2009 7:16 pm
Hi heshamelaziry,

this is an evaluate the argument (or relevant information) kind of question. It is a cousin to strengthen/weaken but not quite the same. The answer choices will not list new information; instead, they will raise considerations that the author did not consider.

In these questions, the author's argument is alsmost always suspect, so a little bit of analysis will pay off by enabling you to predict the right answer, thus saving you valuable time, and precluding the need for POE.

Here: The safety device's function is to decrease to nearly zero the risk of the brakes' failing. But the risk of serious injury due to malfunction of the safety device is 1 in 10,000, and yet the author concludes that automobiles are safer with the device than without. But what if the risk of the brakes' failing (in the first place) was 1 in 100,000,000? Does it still seem correct that cars are safer with the device than without?
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by heshamelaziry » Sat Oct 24, 2009 8:31 pm
Testluv wrote:Hi heshamelaziry,

this is an evaluate the argument (or relevant information) kind of question. It is a cousin to strengthen/weaken but not quite the same. The answer choices will not list new information; instead, they will raise considerations that the author did not consider.

In these questions, the author's argument is alsmost always suspect, so a little bit of analysis will pay off by enabling you to predict the right answer, thus saving you valuable time, and precluding the need for POE.

Here: The safety device's function is to decrease to nearly zero the risk of the brakes' failing. But the risk of serious injury due to malfunction of the safety device is 1 in 10,000, and yet the author concludes that automobiles are safer with the device than without. But what if the risk of the brakes' failing (in the first place) was 1 in 100,000,000? Does it still seem correct that cars are safer with the device than without?


Thanks a lot Testluv; i see what i was missing.

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by badpoem » Thu Apr 14, 2011 6:11 am
IMO (A).

(A) The probability that an automobile driver will be involved in a collision due to brake failure --> On Hold.

(B) The probability that an automobile driver will be involved in any sort of collision --> we are not talking about any sort of collision. We are specifically talking about brake failures here.

(C) The number of automobile collisions that occur for reasons other than brake failure --> out of scope again - need to stick to accidents arising out of brake failures.

(D) The number of new safety features being released that prevent other types of collisions --> again, data about other types of collisions not useful.

(E) The total number of automobile drivers that have had this new safety feature installed --> that would not really prove whether the new safety feature is useful or not. So A.

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by Sharma_Gaurav » Tue Apr 03, 2012 2:00 am
answer (A),
evaluate the argument involves Yes / no answers for the corrrect option.
when the probability of collision due to break failure is too high = then tF is too low than it is not much safer to install this new feature
hence option A is the only one which is correct

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by karthikpandian19 » Wed Jun 06, 2012 5:50 pm
As far as this question is concerned i found that POE is the best method, as i was pushed to select A.
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by alex.gellatly » Thu Jun 07, 2012 5:55 pm
karthikpandian19 wrote:As far as this question is concerned i found that POE is the best method, as i was pushed to select A.
What is POE?

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by karthikpandian19 » Thu Jun 07, 2012 6:57 pm
POE - Process of Elimination technique

The process in which you eliminate all the wrong answers in order to find the right one
alex.gellatly wrote:
karthikpandian19 wrote:As far as this question is concerned i found that POE is the best method, as i was pushed to select A.
What is POE?
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by [email protected] » Wed Jun 20, 2012 12:41 am
Applied the fact test for this question and found that the answer very easily comes out to be an A.

Use the fact test and you find that when a 100% yes is said or answered to the option A, the argument is strengthened. But if a 100% NO is said or answered to the option A then the argument is immediately weakened for that matter.

Hence the correct answer comes out to be A.
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by anujan007 » Sun Aug 05, 2012 3:56 pm
I approached this one using POE and found A as the only relevant answer choice to the argument. Also as rightly explained in the previous posts, the argument states that 1 in every 100 drivers involved in a accident dues to break failure.

If from a total of say 1000 accidents only 1 is going to be due to break failure then effectively 100 break failure accidents might happen in around 100000 accidents. Hence the probability of the break failure accident will best help evaluate the argument.
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by Ganesh hatwar » Tue Oct 16, 2012 11:08 pm
I got A but over skepticism led to E!

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by tanviet » Fri Oct 19, 2012 3:07 am
I get it right but too long because the argument has opening sentence which is wordy and complex and whose purpose is to take our time.

1/100000 failure-----------> is good and should be installed

prethink an assumption: the failure rate is higher than 1/1000000

going to answer choices. A is correct.

all questions test our ability to realize assumption.

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by tavelano » Wed Aug 21, 2013 7:36 am
Think about this in a "math" way:
We have to verify conclusion's inequality: P[Injury|Safety Feature] < P[Injury| No Safety Feature]
We know:
1) P[Injury| Safety Feature]= 1/10,000
2) P[Injury|Safety Feature]= 1/100 X P[collision due to brake failure] - which we don't know

A gives us the variable we need to make the decision. The other answers are irrelevant since they are out of the scope of our decision [to install brake safety feature or not]
heshamelaziry wrote:For every 100 automobile drivers who are involved in a collision due to brake failure, 1 will be seriously injured. A new safety feature exists that is nearly 100 percent successful in preventing collisions due to brake failure. Because the risk of serious injury from malfunction of the new safety feature is one out of 10,000, it is clearly safer for automobile drivers to have this new safety feature installed than not.

Which of the following would it be most helpful to know in order to evaluate the argument?

The probability that an automobile driver will be involved in a collision due to brake failure

The probability that an automobile driver will be involved in any sort of collision

The number of automobile collisions that occur for reasons other than brake failure

The number of new safety features being released that prevent other types of collisions

The total number of automobile drivers that have had this new safety feature installed


OA A I don't see how the answer provides any new information ?

OE[spoiler]This is an evaluation question. If the risk of getting into these collisions due to brake failure is very small and only 1 out of 100 of that small number is seriously injured, it might be safer not to install the new safety feature.


[/spoiler] HOw does this makes sense ?

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by ndqv » Fri Jan 03, 2014 11:15 am
P(injured in a collision due to brake failure) = 1/100
P(avoid collision due to brake failure, with new feature safety) is almost 100%
P(injured due to new feature's malfunction) = 1/10000 => better to have the feature

A) Correct. That the driver can effectively avoid collision themselves even without a brake discourages the use of new feature
B) Out of scope: the stat's concerned about the brake-related collisions, not other kinds.
C) We need to know the percentage, not the specific number.
D,E) Same as C