Residual sum of squares in a normal sample
= Residual sum of squares in a normal sample
For independent $N(\mu,\sigma^2)$ observations, $\sum_i(X_i-\bar X)^2/\sigma^2$ has the $\chi_{n-1}^2$ distribution.
= Residual sum of squares in a normal sample
For independent $N(\mu,\sigma^2)$ observations, $\sum_i(X_i-\bar X)^2/\sigma^2$ has the $\chi_{n-1}^2$ distribution.