N jobs are to be sequenced on a single machine, each job carrying a penalty cost which is a quadratic function of its completion time. The objective is to find a sequence which minimizes the total penalty. Criteria are developed for ordering a pair of adjacent jobs in a sequence and these are incorporated into a branch-and-bound procedure.

The results of this study indicate that the aspect of cognitive style addressed in “the Minnesota experiments” may pertain to a decision maker's choice of a planned or spontaneous solution strategy. Whether or not such a characterization is equivalent to an analytic-heuristic classification is beyond the scope of this note. It would appear that the analytic-heuristic cognitive dimension is a richer and more robust construct. Any MIS/cognitive style implications from “the Minnesota experiments” should therefore probably not be extended beyond the “planned vs. spontaneous” dichotomy that is apparently provided via the AHQ.

Exact solutions to queueing problems with customer interarrival times and customer service times drawn from arbitrary (generalized) distributions have not been found. We are, therefore, much interested in good quality approximate solutions to such problems. This paper presents a methodology for obtaining (approximately) the distribution of the number of customers in a multiserver queue for which both the customer interarnval and customer service times are drawn from arbitrary distributions. The approximation is based on the theory of diffusion, depends only on the means and variances of the interarnval and service time distributions, and as the numeric examples attest is of very good quality when the queueing system is heavily loaded. The approximate solution is obtained via a very simple computational procedure, so that good quality approximate solutions to such problems can be easily produced.

Zmud [Zmud, R. W. On the validity of the analytic-heuristic instrument utilized in ‘The Minnesota Experiments’. Management Sci. (this issue).] has raised some important questions about the interpretation of the cognitive style results reported in “The Minnesota Experiments” [Dickson, G. W., J. A. Senn, N. L. Chervany. 1977. Research in management information systems: the Minnesota experiments. Management Sci. 23 (May) 913–923.]. His specific challenges are (1) the cognitive style instrument used in “The Minnesota Experiments” did not measure the “full breadth” of the analytic-heuristic dimension of cognitive style and (2) research studies must report instrument reliability and validity data to aid the reader in interpreting the results.

The recent paper [Saipe, A. L. 1977. Production runs for multiple products: the two-product heuristic. Management Sci. 23 (12, August) 1321–1327.] by Saipe considers the single-machine multi-product lot scheduling problem, this problem is concened with the determination of run sizes for a set of products which are produced on the same machine. In the paper [Saipe, A. L. 1977. Production runs for multiple products: the two-product heuristic. Management Sci. 23 (12, August) 1321–1327.], a heuristic solution procedure, based on a solution procedure for the two-product lot scheduling problem, is proposed for the multi-product problem. The intent of this note is to raise three issues concerning the proposed heuristic procedure: (a) the optimality of the procedure for the two-product problem, (b) the performance of the procedure at full capacity for more than two products, and (c) the effectiveness of the procedure relative to alternative solution procedures.

This paper describes a multiobjective decision analysis performed to assist in selecting the conductor, tower size, and number of subconductors per bundle for a proposed 765 kV transmission line. Multiobjective decision analysis is shown to provide a systematic, logical framework for handling uncertainty and multiple objectives in this problem.

An applied procedure is preserved in this paper which has been used to forecast some of the political risks ars oil company faces from investment in an overseas developing country, e.g., expropriation, taxation, price and production controls. The procedure makes use of a panel of experts, but requires, their estimates to be formulated in a way that takes explicit account of the precursive conditions for each of the adverse actions that the host country could take. A Bayesian method is used to derive the composite probabilities, for the political risk events under consideration and a Cross-Impact Analysis then provides s means of overall scenario generation.

We describe a production allocation problem which was worked on at Frito-Lay and an integer programming model formulated for its solution. In connection with model formulation, we discuss estimation and collection of the required cost coefficients. Finally, we report on the use of two different linear programs, representing the same integer problem, which gave dramatically different running times to solve the integer programs. Some reasons for the improved running times are given.