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32-10 Verify_Loading_1

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    So this is where we draw the line, any outcome over here is critical.
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    That means so any of those outcomes, you'll be so surprised that we reject the null hypothesis.
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    Whereas any outcome in the region over here is okay, so we accept it.
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    Notice subtlety here. Even outcome 11 is okay.
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    Despite the fact that 11 is very surprising, it comes to the probability less than 5%,
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    but that's not the way to look at this.
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    The more frequently your sample, the more unlikely each individual outcome is.
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    Look at the outcome as blocks.
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    When you implement hypothesis testing, there'll be something like a most likely outcome.
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    Somewhere between 13 and 14, I guess it's 14. That outcome has to be okay obviously.
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    If you see that, you'll be happy and then you push this in one direction towards H₁,
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    the alternate hypothesis until all the probabilities remaining
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    cover 5% or less and that's the critical region.
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    So let's give this another try. Last Saturday, I went to the magic store and bought a loaded coin.
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    I paid a lot of money for it and the wizard that sold me the coin told me
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    the probability of head is equals 0.3.
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    In fact, there are many buckets of coins, the fair ones
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    the slightly loaded, all the way to the fully loaded, and those guys are cheap and those guys are cheap
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    but this one over here was really expensive.
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    So I wanted to make sure that I really got a loaded coin.
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    Let's first ask, what's our null hypothesis. Here are our choices for the probability of heads.
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    Pick the one that's best describes the null hypothesis.
Title:
32-10 Verify_Loading_1
Description:

32-10 Verify_Loading_1

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Video Language:
English
Team:
Udacity
Project:
ST101 - Intro to Statistics
Duration:
01:47
Udacity Robot edited English subtitles for 32-10 Verify_Loading_1
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