Abstract:
We consider a linear model with heteroskedasticity of unknown form. Using Stone s (1977, Annals of Statistics 5, 595 645) k nearest neighbors (k-NN) estimation approach, the optimal weightings for efficient least absolute deviation regression are estimated consistently using residuals from preliminary estimation. The reweighted least absolute deviation or median regression estimator with the estimated weights is shown to be equivalent to the estimator using the true but unknown weights under mild conditions. Asymptotic normality of the estimators is also established. In the finite sample case, the proposed estimators are found to outperform the generalized least squares method of Robinson (1987, Econometrica 55, 875 891) and the one-step estimator of Newey and Powell (1990, Econometric Theory 6, 295 317) based on a Monte Carlo simulation experiment.
More articles in Econometric Theory from Cambridge University Press Address: The Edinburgh Building, Shaftesbury Road, Cambridge CB2 2RU UK Series data maintained by Mike Eden ().
This site is part of RePEc
and all the data displayed here is part of the RePEc data set.
Is your work missing from RePEc? Here is how to
contribute.
Questions or problems? Check the EconPapers FAQ or send mail to .