4. Conclusions
In this paper, we propose a modular and reliable DSS for sales forecasting and order planning in the supply chain management of packaged fresh food products. The proposed DSS combines, in a unique, flexible and easy-to-use software tool, a forecasting module to derive sales forecasts from historical data and exogenous variables, supported by a model selection and tuning module for the automatic choice and configuration of the forecasting method, and a multi-objective optimisation module equipped with an order plan selection module to derive the best order proposal based on a set of KPIs accounting for cost and quality of service. Three different forecasting model families were considered and tested on a set of sample products in a real supply network.
Our results clearly show the benefits of deriving an optimal order proposal based on sales forecasting, explicitly accounting for demand variability and the possible impact of exogenous variables. The proposed analyses highlight the capability of the DSS to absorb relevant differences in terms of forecasting behaviour, thus limiting their impact on the order planning phase. Another advantage offered by this DSS relies on its flexibility, as it is designed to be easy-to-use and to automatically run alternative approaches in terms of forecasting and model tuning techniques, depending on the characteristics of the data-set. In this respect, we notice that the results point out that there is no dominant forecasting model and there is no convenience to use a single model for all the cases (i.e. pairs item/store), and also the performance of a model selected for a specific case might deteriorate over time. Hence, instead of a one-size-fits-all approach, an individual selection including the identification of the best method for each series is considered, though it is more computationally intensive. More specifically, configurations using SPO tend to provide more accurate forecasts, although the computational time, when tuning is required, is higher than the configurations adopting the grid search.