For modeling count data, the Poisson regression model is widely used in which response variable takes non-negative integer values. However, presence of strong correlation between explanatory variables causes problem multicollinearity. Due to multicollinearity, variance maximum likelihood estimator (MLE) will be inflated causing parameters estimation become unstable. Multicollinearity can tackle...

The objective of this paper is to show the usefulness of multivariate statistical techniques to structure and visualize the information contained in multi-criteria matrixes obtained from the evaluation of control strategies in wastewater treatment plants (WWTP). The performance of sixteen different control strategies is evaluated by measuring their degree of satisfaction for twenty-four environ...

OBJECTIVE Recently, changes have been proposed to DSM-IV diagnostic criteria for post-traumatic stress disorder (PTSD) to refine the diagnosis because of concerns about its construct validity. Specifically, Spitzer et al. suggested narrowing the PTSD definition of trauma, specifying a symptom onset time frame after the trauma, and removing symptoms that overlap with other anxiety and mood disor...

This research set out to find out the mate selection criteria among single female teachers. This qualitative study was carried out via thematic analysis approach. Using purposive sampling method, 15 single female teachers aged 18 to 30 years old were identified in Tehran and fifteen semi-structured interviews were conducted. The interviews were recorded, transcribed and then were analyzed using...

Fuzzy regression models has been traditionally considered as a problem of linear programming. The use of quadratic programming allows to overcome the limitations of linear programming as well as to obtain highly adaptable regression approaches. However, we verify the existence of multicollinearity in fuzzy regression and we propose a model based on Ridge regression in order to address this prob...