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18-37 Relative_Raise_Solution

  • 0:00 - 0:05
    And obviously the new mean is 1.2 times the old mean because we're multiplying
  • 0:05 - 0:11
    everything up by 20% raise that makes a factor of 1.2 over here and zero over here
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    because we don't really add a constant amount of money per person its variable.
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    It's a multiplicative change. For the variance it's more interesting.
  • 0:19 - 0:27
    In our new variance, we multiply each salary by a factor of 1.2 and the same is through for the mean.
  • 0:27 - 0:34
    When we look at this, we can bring the 1.2 outside these brackets and it becomes (1.2)².
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    The reason why I squared this, we can bring it outside Xi and u but there's a square over here
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    and we can move it outside this sum as a factor.
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    Now this is true for the variance but not the standard deviation.
  • 0:45 - 0:48
    The standard deviation is cleared of the variance.
  • 0:48 -
    The standard deviation was up by factor of 1.2 only, with a constant offset of zero.
Title:
18-37 Relative_Raise_Solution
Description:

18-37 Relative_Raise_Solution

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Video Language:
English
Team:
Udacity
Project:
ST101 - Intro to Statistics
Duration:
0:57
HelpingHandLN edited English subtitles for 18-37 Relative_Raise_Solution
Udacity Robot edited English subtitles for 18-37 Relative_Raise_Solution
Amara Bot added a translation

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