June 2007 - Sec 2 - LR - Q21
Video Transcript:
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        Question 21, Driver: My friends say I will one day have an accident because I drive my
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        sports car recklessly.
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        But I have done some research, and apparently minivans and larger sedans have very low accident
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        rates compared to sports cars.
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        So trading my sports car in for a minivan would lower my risk of having an accident.
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        All right, so argument or set of facts?
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        Clearly, we have an argument here.
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        The conclusion of this driver is that ?trading my sports car in for a minivan would lower
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        my risk of having an accident.?
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        How do we know that?
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        Well, he's done some research and minivans and larger sedans have very low accident rates
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        compared to sports cars.
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        So minivans and larger sedans have lower accident rates when compared to sports cars.
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        You'll notice that is a correlation.
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        The driver takes that correlation?the minivans and larger sedans having lower accident rates?two
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        things occurring together and turns it into a cause and effect argument in his conclusion
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        because what he says, trading my sports car in for a minivan would lower my risk of having
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        an accident, he's assuming that the minivan is the cause of the lower accident rate.
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        Clearly, this is flawed logic because obviously if he still drives like a speed racer and
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        thinks he's Mario Andretti, he's still going to get into an accident, right?
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        Here, he takes a correlation that minivans have lower accident rates, turns it into a
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        cause and effect argument by saying in his conclusion that trading his sports car in
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        for a minivan would lower his risk of having an accident.
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        Clearly, this is a flawed argument?taking correlation for cause and effect.
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        So looking at the questions then, the reasoning in the driver's argument is most vulnerable
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        to criticism on the grounds that this argument, again most vulnerable to criticism.
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        We have another Errors in Reasoning question.
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        Looking for an answer choice that explains this flaw of mistaking a correlation for cause
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        and effect, we go to (A), infers a cause from a mere correlation.
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        Clearly, that is the flaw, so (A) would be the correct answer.
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        But again, just making sure, (B) relies on a sample that is too narrow?again not the
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        problem here.
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        We do not have a sample that's too narrow.
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        (B) explaining the flaw of overgeneralization from an unrepresentative sample, but again
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        not what we saw here.
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        (C) misinterprets evidence that a result is likely as evidence that a result is certain.
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        Again, the flaw of taking something that is probable and assuming that it will happen
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        for sure, not the flaw that we see in this passage.
        
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        Again, he said that it would lower his risk of an accident, not that he would never have
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        an accident.
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        So (C) is out.
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        (D), mistaking a condition sufficient for bringing about a result for a condition necessary
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        for doing so.
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        So mistaking sufficient for necessary, we know sufficient guarantees necessary, having
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        necessary doesn't tell us anything about whether we have this sufficient condition.
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        Remember, don't just reverse!
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        If all carrots are vegetables, just because I have a vegetable doesn't necessarily mean
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        it's carrot, and that is the flaw (D) is describing, but not what we saw.
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        Moving to (E), relies on a source that is probably not well informed.
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        Clearly, not what we saw in our passage, so (E) would be eliminated.