Comparison between M-estimator and OLS

Today the robust methods become one of the important subjects that pay attention statisticians because it''s estimators have efficient results that are similar to efficient OLS in case of non existing outliers and become more efficient in case of existing outliers in data. In this research two criteria have been used which are (SAZ1 SAZ2) and will apply on barley data in Iraq between (1960-2014). The results that we get and after that we will discuss them in this research and application has been done to compare between Maximum likelihood estimator and Ordinary Least Squares.