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Formula for Location of Median - Intro to Descriptive Statistics

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    After sorting our 27 data values, how do we know that the median was the 14th
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    value besides by simply counting? Is there a way we can describe the median
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    value in symbols? Let's start first by going over some symbolic notation that
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    we briefly mentioned earlier. Remember that these are the rankings, these are
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    not the actual data values, but we can denote the actual value in terms of its
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    rank. So, the value in the first rank would be X sub 1, then X sub 2 for the
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    second rank. X sub 3 for the third, and in the case of Udasiyans Facebook
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    friends, X sub 14 is the median. And remember that any value we can generically
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    denote X sub i where X sub i is the ith value. Yes, we do say ith. So what
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    about for any data set with n values? The median will be different depending on
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    whether or not n is even or odd. Now, this is going to be a really tricky quiz.
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    Which formulas describe the median after sorting the data? There's only one
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    answer for n even and one answer for n odd. Now, really quick, this might look
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    daunting, but just remember that this subscript part corresponds to the rank.
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    So, for example, say there are four values in the data set, n divided by 2
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    means 4 divided by 2 which is 2. So this would mean X sub 2, which is the
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    second value might be the median if n is 4. I'm not saying that's right, I'm
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    just giving you an example. So give this your best short. And again, this
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    should really help get you used to using symbols.
タイトル:
Formula for Location of Median - Intro to Descriptive Statistics
概説:

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Video Language:
English
Team:
Udacity
プロジェクト:
UD827 - Intro to Descriptive Statistics
Duration:
01:42
Udacity Robot edited 英語(米国) subtitles for 06-52 Formula for Location of Median
Udacity Robot edited 英語(米国) subtitles for 06-52 Formula for Location of Median
Cogi-Admin added a translation

English subtitles

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