Statistics Concepts

Posted by alan on 2017-03-22

Statistics Concepts

Covariance

A descriptive measure of the linear association between two variables.

  • A positive value indicates a direct or increasing linear relationship.
  • A negative value indicates a decreasing relationship.

Sample Covariance

sxy=Σ(xix¯)(yiy¯)n1 \LARGE{s_{xy} = \frac{\Sigma(x_{i} - \bar{x})(y_{i} - \bar{y})}{n-1}}

Population Covariance

σxy=Σ(xiμx)(yiμy)N \LARGE{\sigma_{xy} = \frac{\Sigma(x_{i} - \mu_{x})(y_{i} - \mu_{y})}{N}}