## Statistical Rigor Exercise - Intro to Data Science

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Alright. So, why are statistical significance tests useful? So,
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they do provide a formalized framework for comparing and
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evaluating data. And they do enable us to evaluate
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whether perceived effects in our data set reflect differences across
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the whole population. They do not make a bad
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result look good. Significant sets are useful because they provide
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a formalized framework for comparing and evaluating data. Different
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tests have different assumptions and rules that they incorporate, and
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using a particular test ensures that everyone is on the
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same page in so far as what we're assuming about
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our data. Significance tests also enable us to evaluate whether
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perceived effects in our data set reflect differences across the whole
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population. As was the case with our company, where ten
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out of ten people polled preferred the color blue. Sometimes an
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affect that we seen in a small sample does not
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reflect what might be true across the entire population. A statistical
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significance test let's us formally determine whether or not this might
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be the case. Unfortunately, a bad result is not going to
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look any better or worse as a result of using a
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statistical significance test. If our data's
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bad, or there's really no difference
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between our two samples. We're not going to be able to
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undo that with a test. It is possible though that different tests
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might give us different results. The really important thing and we'll
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go into this a bit more is that you need to use
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the right test in the right situations. Why don't we talk a
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little bit about how we might actually run a statistical significance test.
Title:
Statistical Rigor Exercise - Intro to Data Science
Description:

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Video Language:
English
Team:
Udacity
Project:
ud359: Intro to Data Science
Duration:
01:24
 Udacity Robot edited English subtitles for 05-07 Statistical Rigor Exercise Udacity Robot edited English subtitles for 05-07 Statistical Rigor Exercise Udacity Robot edited English subtitles for 05-07 Statistical Rigor Exercise Udacity Robot edited English subtitles for 05-07 Statistical Rigor Exercise Cogi-Admin edited English subtitles for 05-07 Statistical Rigor Exercise

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