PhD positions in Supply Chain Management

The ERIM-LIS (Business Processes, Logistics, and Information Systems) research program consists of three main research themes: (i) Supply Chain Management; (ii) Business Information Management, and (iii) Innovation Management. The reader of this project description on Supply Chain Management is encouraged to visit the other project descriptions within the LIS-program as well.

The aim of the ERIM-LIS research group is to be at the forefront of the developments in its domain and to make major contributions both to management science and to management practice. The research aims to contribute significantly to the leading role of the Netherlands as a gateway to Europe and as an innovative country. Much of the research is inspired by business challenges, and by the new opportunities of innovative information and communication systems, and technologies.

The research in the ERIM-LIS program is inter-disciplinary, integrating both quantitative and empirical research methods. Around the main research themes several research centres have been built (e.g. Smart Port, Behavioural Operations, Closed Loop Supply Chains, Optimization in Public Transport, Procurement, and Future Energy Business), which are used to focus the research, to acquire external funding, and to disseminate the research findings.

Keywords

Logistics, Supply Chain Management, Transportation, Inventories, Port and Terminal Operations, Sustainability, Purchasing and Supply Management, Public Transport, Behavioral Operations Management.

Topic

Subtheme: Supply Chain Management

The research on Supply Chain Management focuses on the management of complete supply chains, rather than on individual parts of the supply chain. This theme covers topics such as collaboration and information exchange in supply chains and contracting, and may even interface with marketing aspects. Also closed loop supply chains, involving both forward logistics and reverse logistics, are studied. The research methods are either empirical, or based on mathematical modelling.

Example projects are the following:

  • Leveraging supply chain structure for sustainable product. Customers are progressively interested in sustainable products and services. Examples of relevant sustainability aspects are the amount of emissions and the quality of labour conditions (“no modern slavery”) throughout the complete lifecycle of the product or service. Supply chain visibility (“product provenance”) may enable managers to make informed decisions in support of credible sustainability claims through certification. However, in quite a few supply chains (e.g. coffee, cocoa, cotton, electronic product), it is not always possible to keep certified and non-certified product separate, due to supply chain complexity. Certifying organisations such as Better Cotton Initiative and Fair Trade have started to use other types of claims, based on certain chain of custody, where certified product may contain non-certified content. This may result in market failure where sustainable product is not able to find its way to consumers that are willing to pay for certified sustainable product. This research aims to develop methods to design mechanisms in international supply chains such that sustainable product as certified matches demand in the best possible way. Distinction can be made between cases where firms need to comply with regulations, and in cases where firms participate in voluntary programs. The research may incorporate the use of enabling information technologies, such as reputation systems in digital social networks and block-chain distributed systems, and attention may be given to the impact of supply chain structure on the effectiveness of visibility and certification systems. Combination of quantitative methods and empirical work may prove useful to address the issues at hand.
    For further information: prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.
  • Risk and security management in global supply chains. Globalization of supply chains provided firms with benefits such as achieving cost efficiency but at the same time it has exposed them to hazards such as violation of intellectual property rights, disruption vulnerabilities, infiltrations of adversaries into legitimate channels, counterfeiting, etc. In this research, we focus on mechanisms to mitigate risks arising from the globalization of supply chains. It has been advocated that risk management in global supply chains calls for an intense collaboration between public authorities and private companies. It is mainly because the information required to detect and manage risks lie at the private parties while the intelligence and resources are owned by public organizations such as customs. One central question arising is what the efficient mechanisms are to initiate and facilitate this collaboration.
    For further information: dr. Morteza Pourakbar: mpourakbar@rsm.nl, prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.
     
  • Omni-channel assortment planning. In today's omni-channel environment consumers increasingly interact with assortments of the same firm across different touchpoints. To provide the seamless experience consumers are increasingly used to, firms have to engage in omni-channel assortment planning; coordinate all aspects of their assortment across different channels. This requires a well-functioning interplay between a firm’s marketing and operations functions; addressing each omni-channel design issue from a dual demand-side (marketing) and supply-side (operations) perspective. The challenges involved in omni-channel assortment planning include strategic, tactical, and operational issues. Strategically, an omni-channel firm has to decide on the optimal level of assortment coordination across the different channels. Traditional retailers (e.g., Albert Heijn, Walmart) have to decide what part of their offline assortment to sell online. How can they offer the long tail while curbing operational costs? Reversely, firms that started off as pure online players (e.g., Coolblue, Casper) need to determine what part of their online catalogue to display in their physical showrooms. Complicating matters is that omni-channel consumers move between the different channels along their journey, a practice that is referred to as research shopping. Consumers may decide to inspect a product in a store, but purchase it online (showrooming) or, reversely, first research the product online before purchasing it in a store (webrooming). This greatly complicates the tactical challenges such as optimizing the assortment composition and layout, which are already quite hard in a single-channel context. Finally, at the operational level coordination is required with respect to information provision, inventory management, and returns management. Tackling these questions will require rich data sets consisting of the historic assortments and sales across several channels of the same firm (e.g., store and web) and, ideally, consumers search behavior. A combination of data fusion, advanced statistical techniques (e.g. Hierarchical Bayes), and optimization techniques (e.g. combinatorial optimization, efficient frontier analysis, very large neighborhood search heuristics) will be required to answer the questions at hand.
    For further information: dr. Robert Rooderkerk: rooderkerk@rsm.nl, prof. dr. René de Koster: rkoster@rsm.nl.

Subtheme: Transport and Logistics

The aim of the research on Transport and Logistics is to improve the performance of passenger transit and cargo transport and logistics systems, usually based on the application of simulation and mathematical optimization methods. The range of applications is wide. (1) Within the SmartPort program, research is carried out on international transportation networks, in particular multimodal land transport, and on terminal optimization; (2) Urban distribution and last mile delivery transportation receive attention, including the use of crowd sourcing opportunities and shared economy principles; (3) Due to our close cooperation with Netherlands Railways (NS), much research focuses on optimization of public transportation. Specific topics of this subtheme include robustness and reliability of transportation systems, fleet composition, design, operations, and planning and control of terminal processes, city distribution, the effective use of information, and revenue management.

Example projects are the following:

  • Stochastic models for the design of automated warehousing systems. Complex automated warehousing systems require sophisticated stochastic models to adequately describe and predict the consequences of variability in processes like picking, transporting, sorting, and buffering. These models have proved their value in supporting practical operations and decision making in, for example, warehouse layout, order scheduling, and product storage. In this project we aim to make a big leap forward in the development of stochastic models, and in particular queuing models, for the design of automated warehousing systems and their interfaces with manual processes. The proposal focusses on the study of stand-alone components, such as storage and retrieval systems, as well as complete warehousing concepts, such as dynamic picking systems, or combinations of picking and sorting systems in interaction with manual processes. Ultimately we envision a hierarchical modelling approach: the results of the stochastic models will provide input to the optimization of the warehouse design.

For further information: prof. dr. René de Koster: rkoster@rsm.nl

Last-mile delivery by means of vehicles and drones. Companies are continuously looking for new ways to improve their last-mile operations. One technology-enabled opportunity that recently has received much attention is the use of autonomous drones (or droids) to make deliveries. One of the key advantages of a delivery drone as compared to a regular delivery vehicle is that a drone is fast and can fly over congested roads without delay. While a drone is fast and has relatively low variable costs, there are also some basic limitations to its use as it can typically only carry one parcel at a time. This means that a drone has to return to the depot after each delivery, which is not very efficient. Since it is battery-powered, the range is likely to remain limited as compared to a regular, fuel-based, delivery vehicle. A regular delivery truck, on the other hand, has a long range and can carry many parcels but is also heavy and slow. One way to extend the effective range and capacity of a drone is to let it collaborate with a conventional delivery truck. From a transportation planning perspective, this gives rise to several new planning problems. In this project, we build on earlier work in our group in which we considered the collaboration between a single vehicle and a single drone (Agatz, Bouman and Schmidt (2018), Optimization Approaches for the Traveling Salesman Problem with Drone). The project may consider various extensions including the deployment of multiple vehicles and/or multiple drones.

For further information: dr. Niels Agatz: nagtaz@rsm.nl, dr. Marie Schmidt: schmidt2@rsm.nl, prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.

  • Robust design of policies for collaborative outbound logistics. The planning and execution of storage and transportation operations is a challenging yet critical contributor to a firm’s operational efficiency. Companies that have been able to ensure fast and cost-efficient delivery, thanks to modern IT infrastructure, have raised customer order and delivery expectations. To this end, firms may engage in horizontal collaboration, i.e., they form joint initiatives to plan and execute storage and distribution operations. The efficient design of such initiatives entails, among others, the assessment of contract structures, cost, information and capacity sharing, and the degree of decision authority of each of the involved parties. This research project is going to extend traditional mathematical optimization models arising in warehousing and transportation systems so that they represent the joint operations of multiple stakeholders, who have engaged in certain contract types. In addition, the models will be amended to capture not only temporal uncertainty (i.e., common supply chain disruptions) but also macro-level risks that may vary across stakeholders. Major risks could be positively correlated for all participants (e.g., a major exogenous supply disruption) or negatively correlated (e.g., trade-specific regulations that could enhance the liquidity of one firm and reduce that of another firm, resulting in tight budget constraints on operations in the latter case). We will try to engage with industry in order to obtain realistic data and validate results.
    For further information: dr. Ioannis Fragkos: fragkos@rsm.nl, prof. dr. René de Koster: rkoster@rsm.nl
     
  • Port performance and (big) data analytics. Sea ports are natural intersections of various logistics networks, involving road, rail as well as waterways. The often intense use of this infrastructure as well as environmental concerns have led to substantive efforts to enhance the efficiency of logistics operations and promote intermodal transport, where cargo transport is moved from land to water in order to reduce road haulage and make better use of inland waterways. Moreover, these efforts are motivated by competition between ports. Carriers and shippers often have a choice as to which port to use for transport, and investors have a choice as to where to invest their capital. The huge interests, the complexity of operations involved, and the variety of stakeholders, emphasize the need for informedness as a basis for coordination, logistics decision making, and continued improvement of port performance. The increasing availability of open data about, e.g. road usage (loop detectors, weigh-in-motion) and ship movements (AIS), provide unprecedented means for decision support, the assessment of environmental impact, insight into the dynamic interaction between trade and infrastructure use, and the performance of port services. The actual use of these data, for this purpose, is however limited. The objective of this project is to explore the use of open data about port-related logistics activities to gain insight into the environmental, logistics and service performance of ports. The outcomes of the project will contribute to the growing body of literature about port performance and the environmental impact of shipping, as well as to regulation by port authorities to combat operational inefficiencies, like congestion, and to enhance port services.
    For further information: dr. Jan van Dalen: jdalen@rsm.nl, prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.
     
  • Urban mobility and sharing economy. The ongoing urbanisation worldwide increasingly challenges the accessibility to resources and urges policy makers at all levels to consider sustainable access to bounded urban and environmental resources. Specifically, access to mobility and related infrastructure is increasingly under pressure as a result of increasing mobility demand and the need of sustainable urban development. Recent years have seen the emergence of typically IT-enabled alternatives to private mobility, based on sharing-economy principles, such as car sharing and ride sharing. This gives rise to many relevant questions related with the potential of these sharing-based mobility forms in the balancing of mobility demand and sustainability needs. For instance, how do individuals choose between own transport means and shared vehicles? How do citizens react to regulations aimed at promoting sharing-based mobility? How do sustainability-induced measures, such as the enabling of electric driving, possibly in combination with sharing, affect mobility choices? Recent studies in this realm have demonstrated, for instance, the importance of psychological disposition, like sense of ownership, in making mobility choices, but have also hinted at the opportunities of new business models for fleet owners of electric cars. The aim of this project is to further explore the effects on sustainable urban mobility of the emerging mobility modes and the complex relations between individual mode choices, innovative mobility solutions and municipal, or even national, policy measures. Research in this domain typically utilizes the increasingly available, heterogeneous data that originates from sensors, social media, cash systems, and other, and takes into account the inter-dependent nature of urban activity. Moreover, research also experimentation strategies in order to gain insight into the drivers of people's choices.
    For further information: dr. Jan van Dalen: jdalen@rsm.nl, prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.
     
  • Mobility, climate change, and economic inequality. Operations management (OM) is at the heart of two critical sustainability challenges in the 21st century: the need to urgently reduce greenhouse gas emissions to avoid catastrophic disruption to the climate, and the need to improve access to ‘good’ jobs to address growing income inequality globally. Nowhere is this more evident than in the transportation industry. This project focuses on how operational decision making can improve the environmental and socioeconomic impact of vehicle production, mobility, and transportation systems, and what role policy can play in realizing these improvements. Candidates could study the impact of operational decisions such as process improvement, material usage, or production localization. Alternatively, taking a desired outcome as a starting point (e.g., good jobs), candidates could study how operational decision making can be improved. In this project, a variety of empirical methodologies –including empirically grounded models, econometric analysis, and qualitative studies—can be applied, as long as the link between operational decision making and environmental and socioeconomic outcomes is explicated. Candidates are explicitly encouraged to make their work accessible to policymakers, and to support the formulation of actionable improvements.
    For further information: dr. Merieke Stevens: mstevens@rsm.nl , prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.

Subtheme: Purchasing and Supply Management

Our research on Purchasing and Supply Management focuses mainly on relational and contractual governance in buyer-supplier relations, and on purchasing strategy. The domains where we study these processes range from manufacturing sectors to the public and service sectors.

Example projects are the following:

  • Open data and procurement analytics. The relevance of purchasing and supply management (PSM) or procurement as a management field has increased substantially, particularly since the 1970s. This is mainly due to increasing specialisation and outsourcing. The costs for acquired goods and services represent the main cost for most organisations – in many cases amounting to more than two thirds of total cost of goods sold. For the same reason, suppliers have become increasingly significant to buying firms as providers of various resources, such as technology. This increased relevance of PSM is not only true for many industries in the manufacturing and service sectors, but also for the public sector and other non-profit sectors.

While traditionally, data in the field of PSM has not been as fine-grained and widely available as in areas such as logistics, rapid development in data analytics and open data open up new avenues for both practitioners and researchers. Financial databases enable firms and researchers to map the supply (and demand) network of individual firms, not just in terms of first tier relations but also further upstream. Network characteristics can then be related to outcomes such as financial or environmental performance. Data on public procurement tenders can be used to investigate, for example, the relationship between type of tendering procedure and need characteristics and tender outcomes such as characteristics of the winning bid. The key question for practitioners is which procurement data can help them most effectively and efficiently in (re-)designing their processes and criteria in identifying, selecting, contracting and managing their supplier relationships. Within this overall topic, there is room to scope out a specific research project for an interested candidate, but our initial interest is mainly related to procurement data to help achieve results in terms of sustainability and product and process innovation.

For further information: dr. Jan van Dalen: jdalen@rsm.nl, prof. dr. Finn Wynstra: fwynstra@rsm.nl

  • Value-based purchasing in healthcare. In order to remain financially sustainable, healthcare systems around the world are trying to make a turn from a system that rewards volume to a system that rewards value. This is not an easy task however. Such a change towards a value-based healthcare system affects both purchasing of care (payers contracting with providers) as well as purchasing for care (providers contracting with their suppliers of goods and services). This transformation may require changes in reimbursement policy, provider/supplier selection, payment and contracting, and relationship management. Key questions include how to incorporate the voice of the end customer (the patient or client) in the purchasing process, how to define quality, outcomes and value, what types of (performance-based) contracts have the best fit, and how to use big healthcare data in purchasing decision-making. There is room to scope out a specific research project for an interested candidate, as long as the research uses empirical research methods and has a particular focus on purchasing processes in the healthcare sector.

For further information: prof. dr. Erik van Raaij: eraaij@rsm.nl.

  • The use of digital tools in buyer-supplier relationship coordination. Organizations worldwide are embracing the notion of digitizing their operations. Digital tools are promised to not only solve classical OM problems related to planning of inventory, logistics, production processes, etc., but to also hold predictive power with regards to problems such as disruptions, machine downtime, and shortages. Unlike traditional internet-based resource planning tools, the new generation of digital tools can collect a wide range of data autonomously and in real time, without interference of a human actor. Using these new opportunities poses a challenge when crossing organizational boundaries - e.g. when digitizing the production facilities of suppliers. Especially how such digital coordination tools interact with buyer-supplier trust, is an important question. Trust in the inter-organizational setting has been defined as a willingness to accept vulnerability based on one’s positive expectations of another’s intentions and behaviour. The question remains whether and how this changes with digital tools autonomously collecting and using information. While candidates are free to pick their industry, previous research in this group has mainly been conducted in the automotive industry.
    For further information: dr. Merieke Stevens: mstevens@rsm.nl , prof. dr. Rob Zuidwijk: rzuidwijk@rsm.nl.

Subtheme: Behavioural Operations

Our research in Behavioural Operations Management focuses on the impact of human factors on company performance, next to planning and control systems. We study the role of humans (managers, workers) in operational processes, in particular the effects of systems design, organizational climate and leadership on worker behaviour, well-being and performance, including innovation. We study leader behaviour, decision making, and implied worker behaviour in interaction with systems, in contexts relevant to society. Example projects in this subtheme are the following:

  • Team decision making and performance: A behavioural study of the Sales & Operations Planning process. The Operations Management (OM) field witnesses a rapidly growing interest in behavioral research, but virtually all studies focus on individual decision-making. How teams make decisions is largely ignored – which is remarkable because operations and supply chain management decisions (sales & operations planning processes) are typically made in teams. Our research focuses on identification and analysis of cognitive and motivational biases that play out in sales & operations planning, including regulatory focus (a yet uncharted area in behavioral OM) and investigates the power of team reflexivity – the extent to which teams reflect on and modify their functioning – to mitigate such biases.

For further information: prof. dr. M. Schippers: mschippers@rsm.nl.

  • Online goal-setting intervention enhances student retention and academic performance. The current project will use an online intervention that has shown to be been extremely successful in raising academic performance and retention rate of students. Especially clearly defined and articulated goals give students purpose and meaning. In the current project, we aim to advance our understanding of these effects by investigating (a) specific changes in student behavior as a result of participating in this program and (b) the testing and implementation of an advanced goal-setting app.
    For further information: prof. dr. M. Schippers: mschippers@rsm.nl.
  • Impact of leader and worker behavior on operational performance. It has been demonstrated in several environments that leadership and employee behavior have a direct impact on operations performance, beyond traditional OM concepts, like planning and control. We aim to study the impact of leadership in warehouse environments where managers and employees can make a difference in performance on safety, quality and productivity. The methods will include experimentation, and company surveys.
    For further information: prof. dr. M.B.M. de Koster: rkoster@rsm.nl.

Approach

The research in Supply Chain Management and Logistics is inter-disciplinary, integrating both quantitative and empirical research methods. The subthemes Sustainability, Transportation and Terminal Optimization have a quantitative orientation towards problem solving: the applied research methods are mathematical modeling (deterministic or stochastic), simulation, and statistical analysis of large data sets. The subthemes Purchasing and Supply Management or Behavioral Operations are more focused on the application of empirical research methods (surveys, case studies, experiments).

Required Profile

Candidates applying for a Ph.D. position in the subthemes Terminal Optimization and Transportation preferably have a quantitative orientation towards problem solving. Experiences with mathematical modelling (deterministic or stochastic), statistical data analysis, computer programming, and model based solving of complex problems in practice are required. Preferred scientific background: Operations Research, Econometrics, Applied Mathematics, or Computer Science.

Candidates applying for a Ph.D. position with the subtheme Purchasing and Supply Management or Behavioural Operations require a background in management studies or economics. In terms of methodological skills, candidates preferably have proven expertise and interest in empirical research methods (surveys, case studies, experiments).

Candidates applying for a Ph.D. position in the subtheme Supply Chain Management can have either of the above mentioned profiles.

Expected output

The research team in Supply Chain Management and Logistics focuses on research that leads to publications in highly ranked scientific journals such as Production and Operations Management, Journal of Operations Management, and Transportation Science. The research in this Ph.D. project also aims at a number of highly ranked publications. Moreover, the open Ph.D. project should lead to the publication of a Ph.D. thesis after 4 years. Nowadays it is usual that a Ph.D. thesis consists of a number of high quality papers that have been published already or that have been accepted for publication.

Cooperation

The position is in the department of Technology & Operations Management (section SCM, Supply Chain Management). Within this department, we have a strong tradition in conducting research that is inspired by business challenges and is often carried out in close cooperation with companies. The SCM Section of the Department of Technology & Operations Management at Rotterdam School of Management offers a high profile MSc Program in Supply Chain Management, one of the world’s best ranked master programs in Supply Chain Management. The SCM section has a large, young, and highly international faculty.

The research team in Supply Chain Management and Logistics is at the forefront of the developments in its domain. As a consequence, it plays an important influential role in large networks, both in the academic world and in industry. Examples of partner companies are: Philips, DHL, DSM, Port of Rotterdam, Albert Heijn, and Netherlands Railways. These networks provide ample opportunities for cooperation. Ph.D. students are encouraged to make a research visit to one of the top universities in the group’s network, such as MIT, University of Bologna, and HEC Montreal.

Societal relevance

Supply Chain Management and Logistics are important to the Netherlands. It is ranked 4th worldwide according to the Logistics Performance Index of the Worldbank. Due to its natural geographical location, the Netherlands and in particular Rotterdam serve as gateway to Europe. A large part of American and Asian multi-national companies have their European distribution centers in the Netherlands. The importance of research in Supply Chain Management and Logistics has been recognized by the Dutch Government, as Logistics is currently one of the nine top sectors that will benefit from research stimulation funds. Also at the European level, Logistics and Transportation are considered as highly relevant areas for research.

Scientific relevance

The aim of the research in the area of Supply Chain Management and Logistics is to be at the forefront of the developments in its domain and to make major contributions to management science. The research aims to contribute significantly to the leading role of the Netherlands as a gateway to Europe and as an innovative country. Much of the research is inspired by business challenges in Supply Chain Management and Logistics, and by the opportunities of innovative information and communication systems, and new technologies. The research group aims at carrying out high quality research that can be published in highly ranked scientific journals. The research group has an excellent publication track record in these journals.

Literature references

Data sources: The research group in Supply Chain Management and Logistics carries out its research in close cooperation with its business partners based on real-world business challenges. The real-world data that is needed for the research is provided by the business partners. 

Literature: A number of relevant papers of the research group are the following:

  • A.M. Arslan, N.A.H. Agatz, L.G. Kroon & R.A. Zuidwijk (2019). Crowdsourced Delivery -- A Dynamic Pickup and Delivery Problem with Ad-Hoc Drivers. Transportation Science, 53 (1), 222-235.
  • K. Azadeh, M.B.M. de Koster & D. Roy (2019). Robotized and Automated Warehouse Systems: Review and Recent Developments. Transportation Science, 53 (4), 917-945.
  • Dul, J. (2016). Necessary Condition Analysis (NCA): Logic and methodology of “necessary but not sufficient” causality. Organizational Research Methods, 19(1), 10-52.
  • De Leeuw, S., Schippers, M. C., & Hoogervorst, S. (2015). The Fresh Connection: Cross-functional integration in Supply Chain Management. In E. Bendoly, W. VanWezel & D. G. Bachrach (Eds.), Handbook of Behavioral Operations Management: Social and psychological dynamics in production and service settings. Oxford: Oxford Press.
  • Schippers, M. C., & Scheepers, A. W. & Peterson, J. B. (2015). A scalable goal-setting intervention closes both the gender and minority achievement gap. Palgrave Communications 1:15014 doi: 10.1057/palcomms.2015.14.
  • Marie E. Schmidt, L.G. Kroon, A. Schoebel & P.C. Bouman (2017). The Traveler’s Route Choice Problem under Uncertainty: Dominance Relations between Strategies. Operations Research, 65 (1), 184-199.
  • Stevens, M., MacDuffie, J.P., Helper, S. (2015). Reorienting and recalibrating inter-organizational relationships: Strategies for achieving optimal trust. Organization Studies, 36(9), 1237-1264.
  • Weele, A.J., & Raaij, E.M. (2014). The future of purchasing and supply management research: About relevance and rigor. Journal of Supply Chain Management, 50(1), 56-72.
  • Wynstra, F., Spring, M. and Schoenherr, T. (2015). Service Triads: A Research Agenda for Buyer-Supplier-Customer Triads in Business Services. Journal of Operations Management, 35, 1-15.
  • Felipe Caro, Charles Corbett, Tarkan Tan, Rob Zuidwijk (2013). Double-Counting in Supply Chain Carbon Footprinting. Manufacturing & Service Operations Management 15(4): 545-558.
  • J. de Vries, D. Roy & M.B.M. de Koster (2018). Worth the wait? How restaurant waiting time influences customer behavior and revenue. Journal of Operations Management, 63 , 59-78.