Influential observations do posed a major threat on the performance of regression model. Different influential statistics including Cook’s Distance and DFFITS have been introduced in literatures using Ordinary Least Squares (OLS). The efficiency these measures will be affected with presence multicollinearity linear regression. However, both problems can jointly exist New diagnostic based Two-Pa...

In this paper, we study the preliminary test method in a linear regression model. The Liu-type estimator is introduced when it suspected that parameter may be constraint to subspace. We also compare estimator, ridge and Liu mean squared error sense.

The Poisson Regression Model (PRM) is commonly used in applied sciences such as economics and the social when analyzing count data. maximum likelihood method well-known estimation technique to estimate parameters PRM. However, explanatory variables are highly intercorrelated, unstable parameter estimates can be obtained. Therefore, biased estimators widely alleviate undesirable effects of these...