BETA-DISTRIBUTED AGE IN MANPOWER-PLANNING MODELS

Many manpower planning models assume age to be normally distributed. I n this paper we have examined the suitability of beta distribution for age. Beta distribution has a few properties, such as finite positive intercepts in the x-axis and adjustable skewness, that make it highly desirable as a distribution for age in a manpower planning model. In t his paper we have developed an approach for dynamically computing the retirement probability, and hence the retirement rate, when the age of manpower in a pool follows beta-distribution. We have made a comparat ive evaluation of the two distributions in the framework of a simple m anpower planning system dynamics model, and we have shown that various manpower-related variables assume more reasonable values for the beta -distributed age compared to the normal-distributed age. Thereafter we have applied the approach to a two-stage hierarchical manpower planni ng model in an R & D laboratory and have studied the behavior of the m anpower-related variables under two recruitment policies. We have demo nstrated in this paper that assuming beta-distributed age presents no difficulty while modelling for time-scale promotion, a combination of time-scale and merit promotion, and recruitment of persons at differen t age groups. (C) 1998 Elsevier Science Inc. All rights reserved.