Dienstag, 21.10.2025, 12-13 Uhr in W9-109

Dr. David Winkelmann
Universität Bielefeld

Data-Driven Approaches for Reducing Food Waste in Grocery Retailing

Grocery retailers face the trade-off between overstocking, potentially generating food waste, and risking customer dissatisfaction through stock outs. To ensure high service levels, many retailers accept excess inventory, contributing to the approximately 11 million tons of food discarded annually in Germany, over 10% of which originates in the retail sector. In collaboration with the German government, major retailers have therefore committed to halving food waste by 2030. Achieving this goal requires more accurate demand forecasts that capture operational complexities. While demand forecasting has been widely studied by the scientific literature, specific challenges remain. For example, retailers frequently apply price reductions to units nearing expiration: such discounts stimulate short-term customer demand and mitigate the risk for food waste, but if these inflated sales figures are not modelled appropriately, forecasts systematically overestimate future demand and perpetuate overstocking. Using data from a major European grocery retailer, this study aims to contribute to the reduction of food waste in the retail sector by improving forecasts for these specific challenges.

 

Dienstag, 04.11.2025, 12-13 Uhr in W9-109

Prof. Dr. Dietmar Bauer
Universität Bielefeld

The more, the merrier: the role of exogeneity in global state space models

Often multivariate time series data has matrix time series structure such that at each point in time the same variables are observed for a number of individual entities. Joint unrestricted modelling using vector autoregressions (VAR) contains a prohibitively large number of parameters. This can be countered in a number of fashions (for example, MaTS, aDFM, Bayesian VARs). These approaches, however, do not include structural information on the relations between the various individuals. The global VAR approach of Pesaran and co-workers provides a different idea: It partitions the model into regional models, each of which is estimated and specified separately, allowing for the imposition of structural relations.
Partitioning uses heavily different exogeneity concepts. In this talk we examine the implications of these exogeneity concepts. We also propose how to proceed, if exogeneity is violated.

 

Dienstag, 18.11.2025, 12-13 Uhr in W9-109

Sophie Potts
Georg-August-Universität Göttingen

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Dienstag, 02.12.2025, 12-13 Uhr in W9-109

Aktuelle Forschungsbereiche des ZeSt

 

Dienstag, 16.12.2025, 12-13 Uhr in W9-109

Jan-Ole Koslik
Universität Bielefeld

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Dienstag, 13.01.2026, 12-13 Uhr in W9-109

Anna Hager
Universität Bielefeld

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Dienstag, 27.01.2026, 12-13 Uhr in W9-109

Pauline Baur
Technische Universität Dortmund

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