Asymptotic expansions are employed in a dynamic regression model with a unit root inorder to find approximations for the bias, the variance and for the mean squared error of theleast-squares estimator of all coefficients. It is found that in this particular context suchexpansions exist only when...

This paper analyzes linear models. It investigates the difference between the sum of squares of the residuals and the sum of squares of the prediction errors when the parameter is estimated consecutively. In case the regressors are “fractionally integrated” (in a very broad sense) it is...