Optimal Aggregation of Multi-Item Production Smoothing Models

This paper presents a method for aggregating multi-item versions of the HMMS model. Necessary conditions are used to reduce the multi-item model to a one-item model. The aggregation technique makes use of the structural properties of the inventory-production part of the model and can be performed regardless the structure of the work force-total production part. Disaggregation of the optimal decisions of the aggregated model gives the optimal decisions of the multi-item model.