WEBVTT
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all right, we're giving the system that's supposed to
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prevent terrorism by just surveillance. So we're giving that
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it has a 99% chance of correctly identifying a future
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terrorists. So let's set some variables. Why equals
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the event that we get a positive reading? Let's
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just phrase that as the event of a positive reading
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, uh, positive reading just for concession and see
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equal the event a subject is the future terrorist.
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All right, we're given that the probability, given
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the subjects of terrorists to get a correct reading,
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a positive reading that 0.99 were also given that the
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probability of correctly I didn't find somebody is not a
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terrorist is 0.999 99.9%. So the probability of not
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getting a positive reading given that the subject is not
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a terrorist zero point 999 were given that in the
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sample 1000 of these people future terrorists 300 million,
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which I'm just gonna abbreviate like that. What is
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the probability that given we get a positive reading,
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that person is a terrorist? And for that we're
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just going to use some base there, so scums
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p t times p. Y t. Why given
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t my fault. Then over this note, that
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should be a plus. Now we have all these
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variables. We just need to take the compliment of
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a few things. So sorry. This Just say
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pft not t equals. So therefore p of t
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prime r t compliment or not tea or whatever you
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wanna call this one minus 1000 or 300 mil and
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P. Why not? Tea equals 0.11 So we
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plug all that in yet 1000 300 mil times 7.99
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all over 100 Sorry. 1000 over 300 mil times
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0.99 plus one minus 1000 with 300 mil times 0.1
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If you do the math, this turns out to
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be 0.32 ish, which is 0.32% now. I
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can't answer the second part of this question for you
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because that's an opinion question. But make of that
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data, what you will is what I'll say