The use of RAS and related models in manpower forecasting

With the increasing availability of statistics describing the occupational structures of different industries manpower forecasters are beginning to develop more sophisticated models. The economic rationale of such models has tended to be obscured by the mathematics involved and an understandable eagerness to put the data to use in forecasting. In addition, the systematic testing of the explanatory power of these models has been neglected where it has not been hampered by the shortage of data series. The RAS model has featured prominently in manpower discussions and this paper attempts an evaluation of its predictive ability and economic interpretation subject to the limits imposed by the data available for the British engineering industry. It is argued that such a model plays a useful initial role in the development of models for sectoral manpower forecasting but must lead on to a more sensitive treatment of the labour market and the decision problem of investing in human capital.