A methodology to establish warehouse productivity measures and warehouse efficiency using DEA.

摘要

The effective use of supply chain performance measures has gained much attention in recent years as companies try hard to find ways to reduce cost, increase productivity and to stay in business. However, there does not appear to be much non-proprietary information available for establishing effective logistics performance measures, especially for general warehousing and distribution facilities.; In this research, a methodology for establishing and implementing warehousing performance measures is developed. This quantitative methodology is focused on labor productivity, since labor cost is the largest single cost component of general warehousing and distribution. Also, a new warehouse efficiency model is presented to evaluate the overall efficiency of a group of warehouses at the enterprise level where multiple inputs and multiple outputs are involved. This model is developed using Data Envelopment Analysis (DEA) as a multi-factor productivity model for measuring the relative efficiencies of a homogeneous set of Decision Making Units (DMUs), or in this case, the set of warehouses used in the study; where the relative efficiency score of each warehouse is calculated in the presence of multiple inputs and multiple outputs.; The research starts with a general review and background on performance measures, warehousing, the DEA model, and basic definitions. The basic (unrestricted) DEA model is applied to a group of homogenous warehouses that have similar inputs and outputs, then, a revised (restricted) DEA model with additional constraints is presented; the revised model incorporates weight restrictions based on expert opinion in conjunction with strategic thinking; thus, incorporating inputs from executives and decision makers who are in charge of setting the organization's goals and objectives. The primary objective of the presented "restricted" DEA model is to move from technical efficiency towards overall efficiency.; The relative efficiency scores for the warehouses used in the study were analyzed before and after the use of weight restrictions. And finally, using the DEA efficiency scores (DEA results) and performing sensitivity analysis and hypothesis testing, we were able to address some of the characteristics and debates around specific warehousing issues.