These four PhD candidates were actively involved in research projects with the KLU faculty and all of them achieved the goal of publishing their results in high-ranking academic journals. The PhD dissertation consists of a collection of relevant research papers. The candidates have been working hard on their papers for the past four to ﬁve years and are now ready for the next step in their professional lives. Olga, Laura, Christoph and Sebastian introduce their ﬁelds of research and give a brief introduction to the topics in which they have immersed themselves. It is also impressive to ﬁnd out where they will start working. Congratulations!
My PhD work involves inventory transshipment issues. The research is targeted to developing guidance for managers on how to move stock between similar retail locations when inventory at some locations is getting low but still remains high at others.
The problem is a result of the uncertain nature of demand. Since the random ﬂuctuation in customer purchases caused by weather conditions and other external factors might result in a signiﬁcant deviation from the expected demand, a predetermined level of inventory based on a forecast might be too high or too low for the real demand level. To even out this mismatch, I propose repositioning strategies that increase sales due to higher product availability and decrease inventory costs.
Depending on the parameters of the retail locations, the beneﬁts of implementing these strategies in inventory management systems could be substantial. After graduating, I plan to continue my academic career. Recently, I accepted an offer from the Krannert School of Management at Purdue University, where I will start as a clinical assistant professor in August.
My thesis is a cumulative dissertation with three independent chapters, each of which has been published or submitted to peer-reviewed academic journals. The overall framework and working title is “Empirical Essays in Operations Management.” In the ﬁrst paper, we study whether or not ﬁrm-level inventories contain relevant information for stock prices that are not already captured by other models (e.g., Fama-French 3-factor model). We show that ﬁrms with extreme inventory dynamics have abnormal stock returns. These ﬁndings are highly relevant for investors, other stock market participants, and top-level managers.
In the second paper, we analyze the inventory in-vestment/divestment behavior of companies in ﬁnancial distress. We show that ﬁrms in these circumstances reduce their inventories as a means of short-term ﬁnancing. Interestingly, ﬁrms that achieve a successful turnaround reduce their inventories more drastically than ﬁrms that go bankrupt later on.
In the third paper, we study whether or not the ordering behavior of Zalando’s customers depends on daily weather conditions and how this knowledge can be used to enhance workforce planning in the retailer’s fulﬁllment centers (i.e., warehouses). When weather data is included in demand forecasting models, we ﬁnd that forecast errors can be reduced by over 50% on summer weekends with extreme weather. Our ﬁndings will be highly relevant for other retailers and in particular, online retailers that may also experience a similar weather effect to Zalando.
In my doctoral work, I have been focusing on both commercial and humanitarian supply chains. Together with my PhD supervisor, Prof. Joern Meissner, I am working to improve stocking decisions for spare parts. The objective is to reduce unnecessary stock without jeopardizing parts availability. The biggest challenge comes from the special characteristics of spare parts demand, which is very erratic and lumpy. Our results provide practitioners with important recommendations on how to reduce their costs when dealing with spare parts.
The research on humanitarian operations in collaboration with Prof. Maria Besiou led me to investigate some of the motives behind donations to humanitarian organizations and the impact of donors’ preferences on operations in the case of dis-aster response programs. Our results are very useful for humanitarian organizations, which can gain insight into how to improve their fund raising strategies, and for donors, to whom we show the beneﬁts achievable by sharing their preferences with the recipient organizations more eﬃciently. After graduation, I will join the European Business School (EBS) in Wiesbaden as a junior professor.
I put my empirical research focus on the intersection of human resource and supply chain management (SCM) – an interdisciplinary domain that has been consistently neglected in academic research despite its critical importance. After all, global supply chains can also be regarded as “human chains.” In view of the severe global shortage of supply chain talent, we should learn more about the people managing supply chains. In particular, my co-authors and I studied the career paths of supply chain executives, the impact of knowledge, skills and abilities on various ﬁrm performance metrics, and recruitment decisions in SCM.
Our research suggests that the cross-functional nature of SCM is reﬂected by the diverse educational backgrounds and working experience of supply chain executives. We also show that highly skilled SCM staff members make substantial contributions to company performance. However, there is still room for improvement: many companies fail to develop SCM competencies further since their corporate training programs are poorly designed. After receiving my PhD, I plan to pursue a career in the ﬁeld to apply the knowledge and tools I acquired in academia.