sarthak Wrote:
——————————————————-
> SEE is basically used to judge the effectiveness
> of the regression model (in sample).
>
> The RMSE is basically the same (divisors are
> different, n vs. n-2) but is derived from the
> errors of the out of sample forecast.
>
> Same formula but different beasts.
>
> Its like me telling you what the last 48 months
> Dow returns are and asking you to come up with a
> regression model and you tell me that using the
> OLS method you derived a SEE of x.
>
> Now we use the same regression model to forecast
> for the next 12 months and compare with actual
> realized returns and calculate the RMSE. If you
> are a betting man you would expect the RMSE to be
> higher than the SEE in absolute terms most of the
> time. This part made up by me, dunno if there is
> statistical proof of probability of RMSE>SEE ?

>
> HTH.
If your model is correct, data stationary, calculate them both right, etc. then they are both unbiased estimators for the same thing. If any assumption is not true then E(RMSE) > E(see)