Why are the two definitions of covariance equal?
138325
Equivalence of two formulas for variance and covariance
10730
Proof that regression residual error is an unbiased estimate of error variance
133568
Is it possible to have a basis for a covariance matrix such that the greatest variance is greater than the variance of the first eigenvector?
20875
Is the product of two Gaussian random variables also a Gaussian?
103876
Covariance between a normally distributed variable and its exponent
77307
Why does inversion of a covariance matrix yield partial correlations between random variables?
61530
Definitions and usage of Covariant, Form-invariant & Invariant?
87800
Covariant derivative ambiguity
105660
Invariance of action $\Rightarrow$ covariance of field equations?
131125
Link between moment-generating function and characteristic function
134031
Is the covariance of standardized variables the correlation?
31388
Why are arrays covariant but generics are invariant?
87448
Why is a sample covariance matrix singular when sample size is less than number of variables?
150910
Covariance and contravariance real world example
94136
Why is variance squared?
122557
Can covariates be categorial variables?
128639
Homoskedasticity Assumption: Var(y|x)=Var(u|x)=constant?