The purpose of this study was to conceptualize and empirically test a model intended to predict statistics performance in reformed introductory statistics courses that analyzes the roles of students individual factors and interpersonal factors and statistics performance. In the predicted model,...

Count data with excess zeros are commonly seen in experiments forimproving electronics manufacturing quality, in medical researchof HIV patients with high-risk behaviors and in agricultural study of number of insects per leaf.Yip (1988) and Lambert (1992) proposed zero-inflated Poisson...