Variance of Sums; Covariance; Correlation

39.1 Why covariance?

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39.2 Variance vs covariance

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39.3 Variance of a sum

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39.4 More facts about covariance

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39.5 Hat problem

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39.6 Continuous example

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39.7 Covariance is linear

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39.8 Correlation

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Practice Problems and Archive of Problems

Practice Problems and Practice Solutions

2014 In-Class Problem Set and In-Class Problem Set Solutions
2015 In-Class Problem Set and In-Class Problem Set Solutions
2016 In-Class Problem Set and In-Class Problem Set Solutions
2017 In-Class Problem Set and In-Class Problem Set Solutions
2018 In-Class Problem Set and In-Class Problem Set Solutions

More practice with variance, covariance, and correlation

2014 In-Class Problem Set and In-Class Problem Set Solutions
2015 In-Class Problem Set and In-Class Problem Set Solutions
2016 In-Class Problem Set and In-Class Problem Set Solutions
2017 In-Class Problem Set and In-Class Problem Set Solutions
2018 In-Class Problem Set and In-Class Problem Set Solutions