In: Statistics and Probability
18. Explain in your own words the reasons, process and limitations of the OLS estimator.
OLS-
ordinary least squares is a type of linear least squares method for estimating parameters(unknown) in a linear regression model. ... Under the additional assumption that the errors are normally distributed, ols is the mle(maximum likelihood estimator)
Ols -
are BLUE (. they are linear, unbiased and have the least variance among the class of all linear and unbiased estimators).. all this, one should not forget the Gauss-Markov Theorem holds only if the assumptions are satisfied...
Assumptions-
1.The regression model is linear in the coefficients and the error term
2.The error term has a population mean of zero..
3.All independent variables are uncorrelated with the error term..
4.Observations of the error term are uncorrelated with each other
5.The error term has a constant variance
6.No independent variable is a perfect linear function of other explanatory variables
7.The error term is normally distributed