讲座主题：Shall We Only Store Popular Products? Warehouse Assortment Selection for E-Companies

      讲座时间：2023年10月15日（周日）上午9点

      讲座地点：经管学院一楼会议室

      主讲人：刘方，中国科学院大学经济与管理学院副教授，博士生导师

      摘要：This paper studies the single-warehouse assortment selection problem that aims to minimize the order fulfillment cost under the cardinality constraint. We propose two fulfillment-related cost functions corresponding to spillover fulfillment and order-splitting. This problem includes the fill rate maximization problem as a special case. We show that although the objective function is submodular for a broad class of cost functions, the fill rate maximization problem with the largest order size being two is NP-hard. To make the problem tractable to solve, we formulate the general warehouse assortment problem under the two types of cost functions as mixed integer linear programs (MILPs). We also provide a dynamic programming algorithm to solve the problem in polynomial time if orders are non-overlapping. Furthermore, we propose a simple heuristic called the marginal choice indexing (MCI) policy that allows the warehouse to store the most popular products. This policy is easy to compute and hence is scalable to large-size problems. Although the performance of MCI can be arbitrarily bad in some extreme scenarios, we find a general condition under which it is optimal. This condition is satisfied by many multi-purchase choice models. Through extensive numerical experiments on a real-world dataset from RiRiShun Logistics, we find that the MCI policy is surprisingly near-optimal in all the settings we tested. Simply applying the MCI policy, the fill rate is estimated to improve by 9.18% on average compared to the current practice for the local transfer centers (LTCs) on the training data set. More surprisingly, the MCI policy outperforms the MILP optimal solution in 14 out of 25 cases on the test data set, illustrating its robustness against demand fluctuations.

      个人简介：刘方，中国科学院大学经济管理学院副教授。博士毕业于美国杜克大学Fuqua商学院运营管理方向，本科毕业于北京大学数学学院。主要研究方向有供应链管理，机制设计，人道主义救援，可持续发展等。现在承担百人计划B项目并曾获CSAMSE会议best paper award二等奖MSOM data research challenge特奖。论文主要发表在国际顶级期刊UTD期刊Operations Research, Manufacturing & Service Operations Management, Production Operations Management等。