Untitled 4

\[ \text{RMSE} \times \sqrt{\dfrac{1}{n}} \times \sqrt{ 1 + \dfrac{(x - \bar x )^2}{ \sigma_x^2}} \]

\[ \text{RMSE} \times \sqrt{ \dfrac{1}{n} + \dfrac{(x - \bar x )^2}{n \sigma_x^2}} \]