Arnold O. Beckman High School, 59 Lowland Irvine, California, USA
Covariance matrix is an important concept in both linear algebra and statistics. It is a square matrix that gives the covariance between element pairs of random vectors. Covariance is similar to but slightly different than the definition of correlation. It does not demonstrate the strength of a linear relationship as correlation (scale of -1 to +1) does, but it allows us to determine the directions of linear relationship between two random variables.
Covariance matrix; random vectors; random variables
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