Difficulties with the interpretation of the parameters of the beta distribution let Malcolm et al. (1959) to suggest in the Program Evaluation and Review Technique (PERT) their by now classical expressions for the mean and variance for activity completion for practical applications. In this...

Purchase frequency modeling began with the pioneering work of Ehrenberg [Ehrenberg, A.S.C., 1959. The pattern of consumer purchases. Applied Statistics 8, 26-41]. This note provides an extension of this work. A collection of some seventeen flexible distributions is discussed for purchase...