Logical Reasoning

PT148 · S1 · Q16 Airport administrator: According to

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Airport administrator: According to the latest figures, less than 1 commercial flight in 2 million strays off course while landing, a number low enough to allow runways to be built closer together without a significant increase in risk.

Conclusion (so)

The figure that 1 in 20,000 commercial flights stray off course while landing is relatively unreliable compared to the figure that 1 in 2 million stray off course.

Evidence

The 1 in 20,000 figure is based on a partial review of air traffic control tapes, while the 1 in 2,000,000 figure is based on a thorough study of the flight reports required of all commercial pilots.

Evaluate

The author is arguing that one figure is more reliable than another figure, because the former is a thorough study and the latter is just a partial review.

We grant the author that thorough review does sound more reliable than partial review. But is that the only difference between the two figures?

One of them is air traffic control tapes, the other is the flight report of the pilot.

Do we have a common sense take on which type of data we would find more reliable: video tapes of the planes landing, from the air traffic control tower or monitors vs. a pilot's written report of the flight

I would trust video evidence over written evidence in most cases. If the video has an unobstructed view of the plane landing, it should be pretty reliable to figure out the rate of stray landings.

When it comes to the pilot's log, I have no idea how seriously they take that task, how soon after the flight they create this report (maybe it's not for hours and their memory of the flight is shaky), or how honest pilots would be in admitting to a stray landing.

Goal

Look for an answer saying that, "a partial review of something more trustworthy (like videotape evidence) might still be more reliable than a thorough review of a less trustworthy source (like a pilot's written remarks).

16.

Which one of the following most accurately describes a flaw in the airport administrator's argument?

  1. The argument presumes, without providing

    Unrelated to Argument: closer runways

    The background fact about potentially building runways closer to each other is not actually part of any of the reasoning that the author does. The argument we're examining is just about comparing the relative reliability of two different sources of information about plane landings.

    1% picked this

  2. Correct

    The argument overlooks the fact

    Why this is right

    This gets at our potential objection that, "Even though the review of the flight reports was thorough, how accurate are these flight reports (compared to video tape)?" This answer is pointing out that if a commercial flight strays off course while landing, that reflects poorly on the pilots. They have a motive to be overly charitable to themselves in terms of adding or omitting "strayed off course on the landing" onto their flight report. If they are sometimes omitting to admit their bad landing in the flight report, then the number we get from them is likely to suggest that stray landings occur less frequently than they really do.

    Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.

    48% picked this

  3. The argument questions the integrity

    Unrelated to Argument

    Unrelated to Argument: closer runways Out of Scope: questions integrity The background fact about potentially building runways closer to each other is not actually part of any of the reasoning that the author does. The argument we're examining is just about comparing the relative reliability of two different sources of information about plane landings. Furthermore, the author never questions the integrity of any opponents of closer runways. In fact, the correct answer is pointing out that the author probably should be questioning the integrity of the pilot's log.

    2% picked this

  4. The argument presumes, without justification,

    Too Strong

    The author doesn't have to assume that air traffic control tapes do not provide accurate information about specific flights. Even if we negate this and say "tapes do provide accurate information about specific flights", the author's argument isn't weakened. She can still argue that, "Yes tapes can provide accurate info about specific flights, but the figure we got from the pilot's reports is still the more reliable figure for the overall rate of stray landings, because it is a thorough study, not a partial review."

    29% picked this

  5. The argument infers from a

    Trap

    Bad Conclusion Match Wrong Flaw: not Unproven vs. Untrue When an Flaw answer choice is structured, infers from X that Y we would ask ourselves if X matches the evidence and Y matches the conclusion. Did the evidence say "there is a lack of conclusive evidence supporting the higher number's accuracy"? Which is the higher number? It's technically 1 in 20,000, because these are fractions, so the smaller the denominator, the bigger the number. For example 1/20 > 1/2000 So did the evidence say something like, "There's a lack of conclusive evidence supporting the figure provided by the air traffic tapes?" No, not really. She said it was a "partial review", so maybe we could fudge that as a lack of conclusive evidence. But since this answer describes one of the ten famous flaws, we probably know that in a real Unproven vs. Untrue argument, the evidence would sound more explicitly like it was shooting down someone's attempt to support the higher number's accuracy. If we tolerated the evidence match from this answer choice, we'd move onto the conclusion. Was the conclusion saying, "the figure from the air traffic control tapes must be inaccurate"? No, too strong. The conclusion was that "the figure from the tapes is relatively unreliable compared to the figure from the pilot's reports".

    19% picked this

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