# Multi-Location Assortment Optimization with Drone and Human Courier Joint Delivery
## 6 Conclusions  
This paper studies the problem of multi-location assortment planning under cooperative delivery by drone and human courier. We use the MMNL model to capture customer purchase behavior. We present a conic quadratic mixed-integer formulation of this problem and strengthen it using McCormick inequalities. We verify that our Conic + MC is effective, and we try to explore the weight distribution under four product marginal revenue structures and give some advice on assortment planning and distribution management for retailers. In general, this work can provide some suggestions for the commercial use of drones and enrich the study of assortment optimization under the MMNL model. For future work, one direction is to consider different stores equipped with different delivery distances. Another direction is to consider other cooperative distribution modes such as truck-drone. Furthermore, our results may also provide some guidance for distribution network setup and revenue management research. Conceptualization, M.W. and Z.P. ; methodology, M.W. and Z.P. ; software, M.W. ; model analysis, M.W. ; investigation, M.W. ; resources, Z.P. ; data curation, M.W. ; writing--original draft preparation, M.W. ; writing--review and editing, M.W. and Z.P. ; visualization, M.W. ; supervision, Z.P. ; project administration, M.W. All authors have read and agreed to the published version of the manuscript. The authors are grateful for the financial support partly from the Natural Science Foundation of China [Grant numbers 72271222, 71871203, L1924063]. Not applicable. The authors declare no conflict of interest. The following abbreviations are used in this manuscript: \begin{tabular}{l l} MIP & Mixed-integer program \\ MILP & Mixed-integer linear program \\ Conic + MC & Conic quadratic mixed-integer formulation with McCormick inequalities \\ MNL & Multinomial Logit model \\ NL & Nested Logit model \\ MMNL & Mixture of Multinomial Logit model \\ IIA & Independence of Irrelevant Alternatives \\  & Multi-location assortment problem under the cooperative delivery by drone \\ MADH & and human courier \\ \end{tabular}   
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