On measures of productivity

The welfare of an individual enterprise, as well as that of the national economy, very much depends on productivity. But it appears that methods for determining measures of productivity are lamentably unsophisticated and lead to many ambiguities and inconsistencies. It is generally suggested that productivity represents some ratio of output to input, but existing measures of inputs and outputs are unsatisfactory, largely because they gloss over the difficulties of reducing multi-inputs and multi-outputs to single denominators. This paper examines certain approaches that may be developed to handle some of the measurement problems involved in this area.     

A productivity study in a chemical plant

This paper describes a case study in the application of a productivity analysis model in a plant producing industrial gases. Although the process is a relatively simple one, several inputs (labour, electricity, capital and some materials) and several outputs (liquid and gaseous oxygen, gaseous nitrogen, argon and a hydrogen-nitrogen mixture) are involved. The case study demonstrates how measures of total input and total output can be applied and analyses the performance of the plant over a 15-month period in terms of a variety of managerial control ratios.     

Multi-product batch production on a single machine—A problem revisited

When several products are processed one at a time on a single machine, the conventional approach of computing the economic batch quantity for each product cannot apply. An example for six products is considered, where the total production capacity on regular time is inadequate, so that overtime has to be used at an extra cost. A simple method is described for solving this problem when each product is produced once during a production cycle, the objective being to minimize the total set-up and holding costs per day. Schedules which involve batch splitting can reduce these costs further, and a guideline is proposed for the construction of sub-cycles. The results compare favourably with lower bounds computed for the purpose.