The Liu estimator has consistently been demonstrated to be an attractive shrinkage method for reducing the effects of multicollinearity. The Poisson regression model is a well-known model in applications when the response variable consists of count data. However, it is known that multicollinearity negatively affects the variance of the maximum likelihood estimator (MLE) of the Poisson regressio...

The modeling of relationships between motor vehicle crashes and underlying factors has been investigated for more than three decades. Recently, many highway safety studies have documented the use of negative binomial (NB) regression models. On rare occasions, the Poisson model may be the only alternative especially when crash sample mean is low. Pearson's X(2) and the scaled deviance (G(2)) are...

Analysis of fatality automobile accident data can be challenging in rural areas where a relatively small number of such accidents occurs on specific sections of highways. Combining crash data from the Fatality Analysis Reporting System (FARS) and highway networks and design specifications from the Oklahoma Department of Transportation (ODOT), this article employs Poisson regression analysis to ...

Declining fertility in developed countries along with rising number of immigrants and different fertility behavior exhibited by the immigrants make the immigrants' fertility an interesting topic in field of demography. However most of the studies on immigrants' fertility consider the female immigrants as their subject on the assumption that they represent the immigrants' fertility. This study t...

aim : this study compared pr and nb in predicting hcv patient costs. the objective of this study was to predict the direct cost of the hcv patient in iran. background : hepatitis c virus (hcv) is a common and expensive infectious disease in iran. cost associated with hcv and its complications has not been well characterized. analysis of cost data is important in providing consistent information...