Covariance is one of those statistical terms that you might have heard before but didn't quite understand. It sounds fancy, but it's really quite simple and it is a computational stepping stone to many other interesting concepts like correlation. This video describes covariance, what it does and doesn't do, how it's computed, and why it is more useful as a computational stepping stone rather than an end in itself.
NOTE: This StatQuest assumes you already know about "variance". If not check out the quest:
https://youtu.be/SzZ6GpcfoQY
And if you are interested in Part 2, which explains Correlation, here's the link:
https://youtu.be/xZ_z8KWkhXE
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0:00 Awesome song and introduction
0:24 Review of variance
1:07 Motivation for Covariance
5:59 Types of Covariance relationships
7:32 How to calculate covariance
17:00 Why covariance is hard to interpret
20:31 Motivation for Correlation
21:20 Summary
Correction:
16:45 We should be dividing by 4-1, not 5-1. Oops! :)
#statquest #covariance