#11 - Some statisticians believe that the method called

[Administrator]

Complete Question Explanation

Must Be True. The correct answer choice is (B)

This stimulus discusses extreme value theory (EVT), which predicts that the limit on human life spans is more than likely between 113 and 124 years, while under traditional statistical models, some humans would live beyond 130 years. Thus far, no one has lived longer than 124 years, the upper limit indicated by EVT analysis.

• Premise: Traditional statistical models estimate human longevity at 130 years.
  
  Premise: EVT predicts human longevity to be between 113 and 124 years.
  
  Premise: No one so far has lived beyond the age predicted by EVT analysis.

This stimulus contains no conclusions, so a Must Be True question is likely to follow. We might note that current statistics seem to conform more closely to models that employ EVT analysis.

Answer choice (A): According to the stimulus, it is not clear that EVT offers a more reliable means of predicting future trends. This answer choice reflects a far broader conclusion than is justifiable based on the information provided in the stimulus. While we can infer that EVT might be somewhat accurate, we cannot conclude that this method is more reliable in general.

Answer choice (B): This is the correct answer choice. This is accurate; no human life span has exceeded the upper limits suggested by EVT, while the highest limit suggested by traditional methods is significantly higher. Thus, based on empirical evidence to date, EVT appears to produce a more accurate model of human life’s upper limit than more traditional models.

Answer choice (C): EVT is a tool of statistical analysis, and just because no person has exceeded the upper limits of EVT projection does not mean that it is physically impossible to do so.

Answer choice (D): The assertion in this answer choice is not supported at all by the stimulus. The fact that EVT projects the upper limit of human life span does not mean that there is no point in conducting research on increasing this upper limit.

Answer choice (E): While the stimulus offers some limited evidence of EVT’s predictive value, the author does not take the rather strong stand represented here, that EVT should eventually replace all traditional forms of statistical analysis, so this answer choice is incorrect.

[MBG13]

Can I have an explanation as to why (B) is right answer. I selected (A).

This is the way I broke it down:

Fact 1: Trad. Stats Human Lifespan 130+
Fact 2: EVT Human Lifespan 113 to 124
Fact 3: No one has lived beyond EVT stats

Prephrase: EVT is more accurate than Trad. Stats.

My prephrase led me to choice (A).

As I'm writing this, I re-read both (A) and (B) and I think that I see the issue for the first time with (A).

(A) talks about "projecting future trends" -- is this what is wrong with (A)

Whereas (B) uses the phrase "EVT fits the data ... more closely than doe traditional methods"

[Clay Cooper]

Hi MBG13,

Thanks for your question.

Answer choice A is wrong because it is too broad; it claims too much. We don't know anything about EVT after reading this question except what its predictions are for the upper limit of human lifespans and the fact that some statisticians think of it as a powerful tool.

This evidence certainly seems to suggest that EVT is worth exploring, and might even be superior to traditional statistical theories in certain applications, but they (even together) do not come close to demonstrating that EVT is, in general, better at making predictions about the future than are traditional statistical theories.

Does that make sense? When in doubt on a MBT question like this one, I try to err on the side of the answer choice that is less broad, the one that claims less; they are easier to defend, and the test-makers have demonstrated a habit of trying to trap students with over-broad answers (see lesson one, common incorrect answer choices in your book).

I hope that helps!

[MBG13]

Okay I got it! Thanks.

[actionjackson]

Hi Powerscore,
I was between answer choices B. and E. here. I ultimately selected B. and I read the explanation for why E was incorrect. But I just wanted to confirm my thinking was correct. On seeing E and comparing it to the stimulus where the author is essentially saying, "These are two inaccurate analytical tools. One is a little closer than the other but they are both off". E says something that was never mentioned in the stimulus. That EVT should replace the traditional methods, but they are both inaccurate? How could that be true? B. says that EVT is the closer of the two. That answer choice Must Be True, was that the Fact Test in action? Should I have just noticed that E was too strong and not have gotten bogged down with this type of thinking?

[Kristina Moen]

Hi actionjackson,

This test is based on language, and you should pay attention to language that indicates that something should happen versus something that does or will happen. The word "should" often indicates an opinion, whereas the word "is/will" indicate fact. "I should go to the gym" and "I will go to the gym" have very different meanings and potentially different outcomes!

Since this is a Must Be True, and the stimulus never gave us language that indicated opinion, the answer choice will not use a word like "should." You can eliminate it straight away based on that word alone.