Q16 - Airport administrator: According to the latest figures

[mshinners]

Question Type:
Flaw

Stimulus Breakdown:
Premise: The admin's numbers are based on flight reports from pilots on all flights, and the opponents' are based on a partial review of air traffic control tapes.
Conclusion: The admin's numbers are more reliable.

Answer Anticipation:
There's no real argument here - just a mention of what the numbers are based on, and a claim that one set is more reliable. We could delve into why the admin thinks her numbers are more reliable (it appears to be the comprehensive nature of them), but that doesn't actually matter! Since we're looking for a flaw, the correct answer much more likely deals with why the admin's numbers aren't more reliable.

When we're looking at numbers in a study, our first thought should always be about the sample. In this case, the size of the sample cuts in favor of the admin. However, the sample itself in the admin's study could be biased - if we're asking about pilot error, we probably don't want to ask the pilots. Let's be on the lookout for an answer that mentions that the pilot's might not be the best source to analyze for problems with their flying.

Correct answer:
(B)

Answer choice analysis:
(A) The author argues that there really isn't much of a risk, not that this change will alter behavior.

(B) Shazam! The admin is relying on numbers from a group that might not be a reliable source. This is the Sampling flaw we were looking for.

(C) Wrong flaw (Ad Hominem). If anything, the objectivity of the pilots is being called into question, not the opponents of the admin's proposal.

(D) Wrong flaw. This answer is where thinking about what the author assumed would be useful. The admin assumes her numbers are more accurate, not that the other numbers are completely inaccurate.

(E) Wrong flaw (Unproven vs. Untrue). First, there's some ambiguity around higher number (1/20,000 is higher, but 2 million is higher). Second, the admin presents her own numbers, so she's not relying on the inconclusive nature of the other side to prove her point. If we removed the 1/2mill study, this answer would be better.

Takeaway/Pattern:
Whenever a survey is done, always check the sample.

#officialexplanation

[IlanaG433]

Thank you for the explanation - I see why (B) is correct.

If there was not an ambiguity with the "higher number's accuracy" mentioned in (E), would this answer be correct? I am having a hard time eliminating this choice since the author argues that the 1 in 20,000 figure is "based on a partial review" and the 1 in 2 million figure is based on a "thorough study." Wouldn't this be an argument that infers a lack of conclusive evidence deems the figure inaccurate? Thanks!

[AndreD935]

Just following up with the question above about answer choice E).

So everything mentioned in the first post sounds great, but I think there’s another crucial part that makes E) incorrect (which I did not see when I was completing my timed PT).

In the stimulus, the airport administrator comments on the partial review evidence by saying: “...and so is relatively unreliable” on lines 8/9.

Answer choice E) says that the argument of the author infers that the evidence of the opponents (that the author deems to be a partial review) “must be inaccurate”.

However we can see that the author stated that the evidence is “relatively unreliable”, which is a fairly large leap from the answer choice claiming that the author believes that this evidence “must be inaccurate”.

In short, the author says the evidence is “relatively unreliable” which does not equate to “must be inaccurate” and so answer choice E) is out of scope. The author may very well think the evidence could be accurate, but that it’s just not absolutely proven to be true!

Hope this helps!

[obobob]

Just out of curiosity, this question is from one of the recent LSAT, and I kind of wonder how mrshinners put the explanation for this question back in 1999. Did this question appear twice?

[ohthatpatrick]

I think tech support did that for all the #officialexplanations, as a means of getting THAT post to "stick" to the top of the page.

[MitchellL341]

Would someone please write another explanation of why B is right and D is wrong? B is not supported in the stimulus. How can we assume that pilots who report straying while trying to land are OFTEN unreliable sources of information? D seems to be the only flaw supported in the stimulus.

[Laura Damone]

Sorry for the delayed response here. We had a technical difficulty that caused your post to be mistakenly categorized and it slipped through the cracks.

Because this is a Flaw question, our task is to describe the argument, not to find an answer that must be true based on the argument. This argument has a Sampling Flaw. It's comparing one data set drawn from a partial review of air traffic control tapes, and another data set that is a complete study of flight reports from the pilots themselves. The first data set, while partial, is more objective. The second data set, because it is self-reported, is more subjective. It's also more likely to be biased, since there's a motivation to suppress information about your own mistakes. That's why B is correct.

D is not supported because the administrator doesn't call on info about specific flights to make their case. Instead, they call on the incompleteness of the air traffic control data set as the reason to prefer the more complete pilot-reported data set.

Hope this helps!