we present an improved implementation of the wagner-whitin algorithm for economic lot-sizing problems based on the planning-horizon theorem and the economic- part-period concept. the proposed method of this paper reduces the burden of the computations significantly in two different cases. we first assume there is no backlogging and inventory holding and set-up costs are fixed. the second model ...

In real-world applications, costs for products are not deterministic: neither static nor dynamic. They actually tend to be non-stationary and cross-correlated. To overcome this drawback, there have been some efforts by researchers to extend the Wagner–Whitin algorithm to consider stochastic costs. However, they assume that the information of probability density function of random costs exists. ...

We present an improved implementation of the Wagner-Whitin algorithm for economic lot-sizing problems based on the planning-horizon theorem and the Economic- Part-Period concept. The proposed method of this paper reduces the burden of the computations significantly in two different cases. We first assume there is no backlogging and inventory holding and set-up costs are fixed. The second model ...

In this paper we study sensitivity analysis of the uncapacitated single level economic lot-sizing problem, which was introduced by Wagner and Whitin about thirty years ago. In particular we are concerned with the computation of the maximal ranges in which the numerical problem parameters may vary individually, such that a solution already obtained remains optimal. Only recently it was discovere...

In this paper, we analyze the performance guarantee of the forward Wagner-Whitin algorithm with rolling horizons. We establish several properties for the solution returned by the algorithm and show that the ratio of the heuristic solution to the optimal cost is bounded above by the degree of speculative motive. Further, we show that the bound is actually tight.

A linear description for the economic lot-sizing problem consisting of exponentially many linear inequalities was given by Barany, Van Roy and Wolsey in 1984. Using this formulation we present a dual algorithm for the economic lot-sizing problem, which is of the same complexity as the Wagner and Whitin dynamic programming algorithm. Besides its use in sensitivity analysis the dual algorithm als...

We present lot-sizing heuristics that are both e cient and stable for the dynamic lot-sizing problem(DLSP) with constant or variable unit costs, including setup, inventory holding and production costs. These heuristics are myopic variants of the forward Wagner-Whitin algorithm with rolling horizons. Large scale computational experiments show that these heuristics considerably outperform other w...

In this paper, the authors propose a non-linear cost function based on ecological considerations for lot-size planning. The classical approaches of lot-size optimization, the Wagner-Whitin algorithm and the Part-Period Balancing heuristic, are enhanced with so-called eco-factors. These eco-enhanced approaches combined with eco-balancing help to reduce overall production costs. Simultaneously, t...