Estimators of the Parameters of the Quadratic Trend Model and Their Characteristics. Additive Case

Abstract

This paper discusses the Buys-Ballot estimators of the parameters of the quadratic trend model and their characteristics with emphasis on the additive model. The aim is to obtain estimators of the parameters of the series that admit the additive model. Stimulation examples are used to illustrate the characteristics of the additive model while comparing them with those of the multiplicative and mixed models. The method adopted in obtaining the estimators of the parameters are those proposed for the series that admits additive model. The results indicate that Buys-Ballot estimates for the additive model have characteristics slightly different from those of the multiplicative and mixed models. The difference occurs in the standard deviations. The standard deviation of the additive appears linear while those of the multiplicative and mixed models appear curvilinear.