A new crew scheduling optimization system has been developed for United Airlines. The system was developed to permit quick response to schedule changes and to reduce crew scheduling costs. It was designed to work efficiently for both the medium sized problems (300 flights daily) and the very...

A complete, unified description is given of the design, implementation and use of a family of very fast and efficient large-scale minimum-cost (primal simplex) network programs. The class of capacitated generalized transshipment problems solved includes the capacitated and uncapacitated...

A dynamic factorization algorithm is developed which uses a partition of the basis to permit the simplex method to be executed from a small working inverse and a small, sparse triangular submatrix of the basis. This partition is maintained dynamically using spike swapping in a way which seeks to...

We propose and test a new pricing procedure for solving large-scale structured linear programs. The procedure interactively solves a relaxed subproblem to identify potential entering basic columns. The subproblem is chosen to exploit special structure, rendering it easy to solve. The effect of...

A stochastic model of purchase behavior is developed to aid marketing managers analyze and predict consumer purchase behavior. The model is based upon a composite structure, that is, it integrates several submodel components (e.g., brand choice and purchase incidence behavior) within its...

A stochastic model is developed with application to both the study of consumer behavior and the scheduling of advertising media. This model incorporates a stochastic response behavior model which examines changes in brand purchase probability over time through the integration of consumer...

In a previous article, a new model of brand choice and purchase timing behavior has been discussed with respect to its theoretical foundations and mathematical development (Zufryden, F. S. 1977. A composite heterogeneous model of brand choice and purchase timing behavior, theoretical...

A stochastic model is proposed to study the effect of advertising on consumer purchase dynamics by specifically relating the distribution of exposures, from a brand's media schedule, to brand purchase incidence behavior patterns over time. The approach is based on underlying individual consumer...

A note submitted to Management Science by Lodish [Lodish, L. M. 1975. A note on modelling the relationship of diminishing returns to media overlap for the media planning problem. Management Sci. 22 (1, September) 111-116.] comments on a media model previously published in this journal [Zufryden,...