Two regression methods can be interpreted as based on Gini's mean difference (GMD). One relies on a weighted average of slopes defined between adjacent observations and the other is based on minimization of the GMD of the errors. The properties of the former approach are investigated in a multiple regression framework. These estimators have representations that resemble the OLS estimators, and ...

nasonovia ribisnigri (mosely) is one of the most important pests of the lettuce plant and it was reported for the first time in ahvaz in 2008. in order to investigate the dominant species of its natural enemies and their population fluctuations, sample were taken arbitrarily from fifty plants twice a week during the growing season in 2010-2012. in this study, ten species of predators, three spe...

empowering employees in specialized and general qualifications fields is required for urban management organization (tehran municipality). planning and establishment of comprehensive system of electronic learning is considered the main goal of human resource and educational managers. . this study tried to investigate the feasibility and execution of electronic learning courses for in-service st...