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Should we replace traditional grading methods with lie detector tests?

  1. Dec 20, 2006 #1
    <sarcasm>Since lie detector tests are very very accurate (like 99%), we should use them as an alternative for human grading. So what do you think? I believe it would obviously work due to the use of the lie detector test in law enforcement. It can save the teacher a lot of time because since the lie detector test knows what is a lie and what is a truth, rather than what is a matter of opinion, feeling, or subjective subconscious inference, it can be used to assess the correctness or wrongness of essays, mutiple choice answers etc. All we have to do is to connect the student to a lie detector while they are giving responses to questions!</sarcasm>
  2. jcsd
  3. Dec 20, 2006 #2
    Did one of your teachers suggest this or something?
  4. Dec 20, 2006 #3
    I think I could beat the test.
  5. Dec 20, 2006 #4


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    They aren't 99% accurate.

    They probably usually range between 88% and 92% accurate.

    Note: I searched for some reference, but couldn't find a good one. My searches get flooded with anti-polygraph sites and other non-sense.

    Should we use for educational purposes? If your goal is to reduce your freedoms, then yeah, but for me, hell no.
    Last edited: Dec 20, 2006
  6. Dec 20, 2006 #5
    Of course. But I am 100% sure that the those percentage of accuracy cannot be replicated for all individuals. I am 100% sure that it has some level bias particulary against those with physiological problems or differences. Otherwise we could use them for education gdamit. So why don't we? We could save billions in education (if it actually does what it claims!)

    Just divide by .88 or .92 to get the real grade!
    Last edited: Dec 20, 2006
  7. Dec 20, 2006 #6


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    Even if it's accuracy were 99%, a lie detector would only show whether the amount of confidence the person had in his answer, not whether the answer were actually correct.
  8. Dec 20, 2006 #7
    <sarcasm>No. I believe that a lie detector test can detect lies. It can determine which philosophies are invalid.</sarcasm>
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