Template-type: ReDIF-Paper 1.0 Author-Name: Vanessa Berenguer-Rico Author-Workplace-Name: Department of Economics and Mansfield College, University of Oxford Author-Email: vanessa.berenguer-rico@economics.ox.ac.uk Author-Name: Søren Johansen Author-Workplace-Name: University of Copenhagen and CREATES and Aarhus University Author-Email: soren.johansen@econ.ku.dk Author-Name: Bent Nielsen Author-Workplace-Name: Department of Economics and Nuffield College, University of Oxford Author-Email: bent.nielsen@economics.ox.ac.uk Title: Models where the Least Trimmed Squares and Least Median of Squares estimators are maximum likelihood Abstract: The Least Trimmed Squares (LTS) and Least Median of Squares (LMS) estimators are popular robust regression estimators. The idea behind the estimators is to find, for a given h; a sub-sample of h good observations among n observations and estimate the regression on that sub-sample. We find models, based on the normal or the uniform distribution respectively, in which these estimators are maximum likelihood. We provide an asymptotic theory for the location-scale case in those models. The LTS estimator is found to be h^1=2 consistent and asymptotically standard normal. The LMS estimator is found to be h consistent and asymptotically Laplace. Keywords: Chebychev estimator, LMS, Uniform distribution, Least squares estimator, LTS, Normal distribution, Regression, Robust statistics. Length: 39 pages Creation-Date: 2019-09-01 Number: 2019-W05 File-URL: https://www.nuffield.ox.ac.uk/economics/Papers/2019/2019W05_LTS_MLE_1sep2019.pdf File-Format: application/pdf Handle: RePEc:nuf:econwp:1905