Article ID: | iaor2002172 |
Country: | Germany |
Volume: | 89 |
Issue: | 3 |
Start Page Number: | 487 |
End Page Number: | 504 |
Publication Date: | Jan 2001 |
Journal: | Mathematical Programming |
Authors: | Wolsey L.A., Pochet Y., Loparic M. |
We examine a variant of the uncapacitated lot-sizing model of Wagner–Whitin involving sales instead of fixed demands, and lower bounds on stocks. Two extended formulations are presented, as well as a dynamic programming algorithm and a complete description of the convex hull of solutions. When the lower bounds on stocks are non-decreasing over time, it is possible to describe an extended formulation for the problem and a combinatorial separation algorithm for the convex hull of solutions. Finally when the lower bounds on stocks are constant, a simpler polyhedral description is obtained for the case of Wagner–Whitin costs.