0:00:00.012,0:00:05.092
>> Here's another way to look at it. Let's say you have a bag of jellybeans.
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There's only one licorice, but there are four strawberries and four blueberries.
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There's also only one cherry and two lime, or lemon, I don't know, you decide.
0:00:16.320,0:00:21.656
If we take a sample of, say, four Jelly Bellies, most likely, we're not going to
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get the licorice one. Say we just get these in our sample. This sample doesn't
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show the whole range of Jelly Belly flavors that we have, including cherry and
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licorice. So our sample underestimates the variability in our Jelly Belly
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population. Hopefully, this example lends a little more insight into why we
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divide by n minus 1 when calculating the standard deviation of a sample. But
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please let's discuss it in the forums. There, we could go into a lot more depth.
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For the purposes of this class though, as long as you have a basic intuitive
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understanding of the difference between sample standard deviation and population
0:01:01.385,0:01:03.930
standard deviation, then you'll be fine.