ROBUST ESTIMATION AND HYPOTHESIS TESTING IN 2k FACTORIAL DESIGN

The topic of this work is an extension of our previous work on robust 2k factorial design with Weibull error distributions. In this paper, we obtain robust and e¢ cient estimators of the parameters in the 2k factorial de- sign by using the methodology known as modi.ed maximum likelihood (MML) and propose new test statistics based on MML estimators for testing the main e¤ects and the interactions when the distribution of error terms is general- ized logistic. We show that the proposed test statistics are more powerful and robust than the traditional test statistics based on the least squares (LS) estimators.