A microcomputer-based heuristic for tour scheduling of a mixed workforce

Abstract

Labor tour scheduling research has recently addressed environments which allow both full- and part-time employees with varying cost and productivity levels. Mathematical programming representations of the associated scheduling problems have most frequently been based upon the general set-covering formulation originally suggested by Dantzig. A number of heuristic solution methods appropriate for these problems utilize the LP solution of the general set-covering formulation. However, these methods typically require substantial amounts of CPU time for large problems. Continued increases in problem size may result in mathematical programming formulations which are essentially intractable, regardless of the hardware and software used. In this research, a two-stage heuristic for mixed-workforce tour scheduling problems was implemented on a 386 microcomputer. The performances of the new heuristic were compared to those associated with single-phase linear programming-based procedures on mini computers in two test environments. Using considerably lower CPU times, our new method resulted in mean labor scheduling costs which were only 0.36 above and 0.19% below those obtained by the competing methods for these two environments, respectively. The latter result was especially impressive since the problems in the second test set were considerably more difficult than those in the first test set. These results are likely to be important to service operations managers who are often limited to the use of microcomputer hardware and software.