Stefan Spinler

WHU – Otto Beisheim School of Management | WHU ·  Supply Chain Management Group

Purpose The e-commerce boom presents new challenges for last-mile delivery (LMD), which may be mitigated by new delivery technologies. This paper evaluates the impact of mobile parcel lockers (MPL) on costs and CO 2 equivalent (CO 2 e) emissions in existing LMD networks, which include home delivery and shipments to stationary parcel lockers. Desig...

In this paper, we introduce the Special Issue on Machine Learning Methods and Applications in Large-Scale Route Planning Problems, which draws its inspiration from the academic community’s positive reception of the 2021 Amazon Last Mile Routing Research Challenge. We provide a structured overview of the papers featured in this special issue, and br...

This study examines carbon emissions from European land transportation, considering spatial autocorrelation patterns. Using global and local Moran's I indices, we find evidence of positive spatial autocorrelation in the panel data of 26 European countries from 1995 to 2019. To adequately analyze the factors influencing transport emissions, we then...

Humanitarian workers often operate under highly stressful conditions, view emotional scenes, and face high time pressures. This may bias managerial decision‐making in humanitarian logistics, but evidence is lacking. We model humanitarian logistics decisions in an adapted newsvendor setting. We experimentally expose participants to time pressure, no...

Competitive pressure, individualization, and constantly advancing technologies require manufacturers to gain knowledge about their customers to offer well-adapted solutions. Despite being an indispensable resource for achieving a competitive advantage, managing customer knowledge is an enormous challenge that quickly becomes a complexity trap, unle...

The majority of warehouse expenses is driven by labour cost. Therefore, efficient management of labour resources is required. To do so, workforce planning is used to match the workforce capacity with the incoming workload. While doing so, it is often wrongly assumed that each worker has the same and constant capacity or performance. Addressing this...

Purpose Last-mile delivery is associated with a negative environmental impact and high costs. The purpose of this paper is to develop an approach to designing stationary parcel locker (SPL) networks while minimizing both CO 2 equivalent (CO 2 e) emissions and costs during delivery and pick-up. Design/methodology/approach This study uses a multinom...

We build a predictive maintenance model for material handling equipment that incorporates novel data sources to forecast breakdowns. To this end, we develop a framework to structure and extract relevant predictor variables. Subsequently, we conduct a comprehensive study of statistical learning methods for failure detection. We show that the standar...

Quality issues in supply networks can adversely affect the performance of suppliers and their downstream customers. Since suppliers might fail to comply with quality guidelines, decentralized quality controls by each firm in a supply network may be insufficient; thus, a complete network perspective on risk management could help to minimize supply d...

Last-mile delivery (LMD) has experienced tremendous growth in recent years, primarily driven by e-commerce. The LMD sector is characterized by strong competition, with new entrants addressing unexplored business segments, while digitization and more sustainable operations are shifting current industry standards. This paper explores upcoming trends...

Nowadays, global economic production is organized around a complex system of highly interdependent supply chains that are currently enormously disrupted due to COVID 19. What would happen if a fast-growing risk could pose a more significant threat to our supply chains? Are our supply chains resilient to climate change? Even though governments, busi...

More than 60 waste incineration plants (WIPs) are active across Germany. WIPs have various levels of automation, but they still rely on manual operations by human operators. Human operators tend to rely on a few operational levers and infrequent interventions to manage the complex combustion process. Consequently, the combustion process is managed...

Even though customer integration (CI) is very important for the development of products and services, it remains an immense challenge in practice due to fragmented approaches. Therefore, a multidisciplinary approach is required to improve the industrial applicability of CI without falling into a complexity trap. This article contributes to the exis...

Low-cost carriers (LCCs) of the long-haul type have gained momentum in the years pre-COVID19, and on North Atlantic routes in particular. Yet their market impact on fare levels has never been evaluated, and findings related to short-and medium-haul LCCs cannot be readily applied to the long-haul case. We assess the effect, on market fare levels, of...

Previous studies have identified key trends affecting the door-to-door air travel chain, to inform organizational decision making. However, the extent to which transport service providers consider strategically relevant trends remains unclear. This study adopts the novel scope of door-to-door air travel in applying multi-labeled text classification...

Meal delivery platforms like Uber Eats shape the landscape in cities around the world. This paper addresses forecasting demand on a grid into the short-term future, enabling, for example, predictive routing applications. We propose an approach incorporating both classical forecasting and machine learning methods and adapt model evaluation and selec...

The Delphi technique is a suitable methodology for structuring group communication to answer current and prospective research questions within several rounds. The method is used in many disciplines and characterized by anonymity, iteration, controlled feedback, and statistical “group response” (Rowe & Wright, 2001). This technical paper presents pr...

Limited research exists that investigates how big data can be used to optimize delivery times for customers. The goal of this paper is to develop a prediction model for anticipatory shipping, which predicts customers’ online purchases with the aim of shipping products in advance, and subsequently minimizing delivery times. Results indicate that cus...

Intermodal, door-to-door (D2D) travel is gaining momentum for airlines, airports, and feeder traffic providers. At the same time, competition is increasing; having a better understanding of future travelers’ requirements regarding D2D mobility is crucial for the mobility sector, for planning long-term, adapting products and services accordingly, an...

We present a real options approach to evaluate technology and capacity choices under regulatory uncertainty. Our two-phase, regime-switching model includes the option of investing in different technologies as well as a charter and layup option, respectively. For a base-case version of this model, we derive an analytical solution before studying the...

Businesses like Airbnb have shown that a successful circular economy (CE) business can operate exclusively online. Although online communication and web appearance attributes have been subject to academic research given accelerated digitization, there is still a lack of knowledge about online attributes and their role in facilitating CE. We close t...

Current trends related to increased sustainability requirements, the application of new digital technologies, and changes in consumer behavior have disrupted conventional food supply chains, entailing challenges for the last mile logistics and distribution of food products. The main aim of this study is to develop a toolset for exploring the sustai...

We conducted a random allocation experiment at fashion week in Berlin in 2017, testing how face-to-face (f2f) communication affects sales of a fashion start-up focusing on second-hand. The experiment revealed that 11% of guests of an f2f event afterwards turned paying customers with an average basket size 11.8% higher than the overall sales event a...

Germany is by far the largest contributor of greenhouse gas emissions in the European Union but adopted its own climate action plan to achieve greenhouse gas neutrality by 2050. The country’s third-largest emitter of greenhouse gas emissions is the transportation sector. As of January 2019, 99.7% of heavy-duty trucks registered in Germany run on di...

The objective of this paper is to explore the impact of autonomous trucks on business models in the automotive and logistics industry. A Delphi-based scenario study for the year 2040 was conducted, resulting via fuzzy clustering in the identification of three meaningful futures we refer to as cooperation and partnerships, OEM's business model under...

As the number of car models in the automotive industry increases, automotive manufacturers are increasingly implementing multi-model assembly lines. These require more part numbers at the assembly line, which results in a shortage of space at the line. Manufacturers use a broad range of line feeding policies to achieve feasible solutions and lower...

This research paper is concerned with potential barriers to the transition to a circular economy business model (CEBM) on the firm-level. Using a case study in the electronics manufacturing industry, we identify and analyze barriers in terms of their impact along the value chain (VC) as well as the level of difficulty required to overcome them. Thi...

The transport sector is the third-largest producer of greenhouse gas (GHG) emissions in Germany, but within the scope of the government’s climate action plan, the country aims to cut emissions from transport by at least 40% by 2030. Apart from passenger cars, commercial vehicles including heavy-duty trucks (HDTs) are one of the main contributors of...

Purpose As most models focus on a specific question (Alard et al., 2014), the effect of multi-parameter optimization is surveyed in the presented paper. To overcome the often cited data availability problem, when implementing Total Landed Costs (TLC) or Total Costs of Ownership (TCO) models, the paper surveys the capability of simplified models, w...

Supply chain effectiveness and general societal prosperity, as well as economic and ecological productivity will be highly affected in the next decades, entailing challenges for the supply chain and logistics sector. Thereby this sector plays a significant role within the transformation process of economic systems, yet the capacities of it remain u...

A quantitative pilot survey based on 32 interviews with industry experts indicates that a standardized Total Landed Cost (TLC) approach is not routinely adopted, despite a very broad range of potential applications. This paper analyses the current state of TLC implementation including barriers, relevance and success factors differentiated between t...

In this paper, we provide arrival time prediction combined with a cost index optimization model for short haul flights. Our work is based on flight data of a European network carrier. We focus on predicting the arrival time for incoming flights at two hub locations. Airlines focus on two aspects in their operations: Minimizing cost while ensuring o...

Purpose Large-scale projects are the typical delivery model in the engineering and construction industry, with their very own characteristics. Even though well established, only 1 in 1,000 large-scale projects is successful (Flyvbjerg, 2011). A lack of effective supply chain risk management (SCRM) has repeatedly been identified as one of the main...

We present a real options model for capacity expansion that introduces uncertainty about potential future regulation (regulatory uncertainty) and key characteristics of capacity decisions: investment with time to build, divestment, the option to charter, and operating flexibility. Regulatory uncertainty is modelled as a possible jump in operating,...

Rapidly evolving infectious disease epidemics, such as the 2014 West African Ebola outbreak, pose significant health threats and present challenges to the global health community because of their heterogeneous geographic spread. Policy makers must allocate limited intervention resources quickly, in anticipation of where the outbreak is moving next....

Low cost carriers (LCC) have smaller cost advantages on the long- than on the short-haul compared to network carriers (FSNCs). Hence, revenue competitiveness is critical. To evaluate long-haul LCC performance, this paper contributes a new metric for bench-marking the revenue per equivalent flight capacity. Second, a revenue model combining traffic,...

We present a stochastic dynamic capacity investment model that incorporates strategic bidding of generators, price elasticity of demand, and ramping constraints. The model is based on an iterative procedure of finding an equilibrium electricity price forecast closely depicting real-world investor behavior. We assess the robustness and the total cos...

Existing academic literature is inconclusive about characteristics and viability of the long-haul low cost airline business model, whereas several airlines of this type are emerging. This article aims to validate its defining characteristics by clustering a sample of 37 transatlantic airlines using principal component and hierarchical cluster analy...

Female carriers of a BRCA1 or BRCA2 genetic mutation face significantly elevated risks of cancer, with 45%-65% of women developing breast cancer and 15%-39% developing ovarian cancer in their lifetimes. Prophylactic surgery options to reduce cancer risk include a bilateral mastectomy (BM), bilateral salpingo-oophorectomy (BSO), or both surgeries. N...

The number of factors driving the uncertain dynamics of commodity prices has been a central consideration in financial literature. While the majority of empirical studies relies on the assumption that up to three factors are sufficient to explain all relevant uncertainty inherent in commodity spot, futures, and option prices, evidence from Trolle a...

This paper develops an integrated alliance formation and investment simulation model within container shipping. In light of low profitability and frequent alliance changes, the optimal choice of investment approach is addressed. This is achieved by comparing the performance of three investment approaches: real options analysis, and individual and c...

We discuss our development of a decision model that allows La Poste, the French national postal operator, to assess the cost benefits of merging the urban mail and parcel delivery networks, which were run previously as separate entities. Our model, based on a mixed-integer linear program, derives the optimal network structure, including direct deli...

We develop a container industry-specific real options investment model in oligopolistic competition taking into account endogenous price function, fuel-efficient investment, endogenous lead times, and endogenous price formation in the second-hand vessel market. We assess how optimal capacity is influenced by competitive intensity, number of players...

Purpose – From a synthesis of literature, the purpose of this paper is to present a conceptual risk management framework, showing the effect of logistics outsourcing on the supply chain vulnerability (SCV) of shippers. The framework is designed to assist practitioners and academics in better understanding the key research, management as well as op...

The capacity of renewable energy sources (RES) has grown rapidly worldwide, and this growth has benefited from such support schemes as renewable portfolio standards (RPS), feed-in tariffs (FITs), and market premia (MP). Previous research concentrated on comparing the effectiveness of these policy instruments at driving RES investment, but the field...

We present a large-scale static and deterministic mixed-integer linear programming (MILP) model solving a two-echelon capacitated location-routing problem (2E-CLRP) with modal choice in the context of urban logistics services (ULS). This model aims to support the development of profitable ULS by guiding the strategic decision making of postal opera...

Rising feed-in from renewable energy sources decreases margins, load factors, and thereby profitability of conventional generation in several electricity markets around the world. At the same time, conventional generation is still needed to ensure security of electricity supply. Therefore, capacity markets are currently being widely discussed as a...

Interrelationships and feedback loops between different enterprises in a supply chain are widely acknowledged to create additional challenges for risk identification and monitoring. However, each individual manufacturing enterprise is also characterized by interrelationships between its internal operational risks. Our paper investigates these inter...

We analyze the option to breach a leasing contract when replacing a fleet of ICVs (internal combustion engine vehicles) and EVs (electric vehicles) subject to cost uncertainty. We derive the optimal policy for technology choice and breaching ICV contracts. The decision to breach is shown to offer both cost savings resulting from reduced ICV operati...

Increasing product and service complexity, outsourcing, and globalization lead to complex and dynamic supply networks. Within supply networks, interrelationships and mutual connections among supply risks often create additional challenges for risk monitoring. During normal operation, risk interrelationships remain largely hidden until the occurrenc...

This article considers the optimal pricing of full-service (FS) repair contracts by taking into account learning and maintenance efficiency effects, competition from service , and asymmetric information. We analyze on-call service (OS) and FS contracts in a market where customers exhibit heterogeneous risk aversion. While the customers minimize the...

The objective of this manuscript is to introduce a decision methodology that allows manufacturing firms to evaluate which supplier is the most suitable partner for the implementation of a collaborative CO2 reduction management approach. The decision problem is developed for the fast-moving consumer goods (FMCGs) industry, which currently ranks amon...

Within the sustainability arena, CO2 reduction has emerged as a key challenge for manufacturers in the fast-moving consumer goods industry. This goal needs to be balanced against competitive the priorities of cost and responsiveness. Emissions-reducing efforts are driven by the need to comply with expectations from industry and end-customers and by...

Renewable energy sources (RES) capacity has grown globally at a rapid rate benefiting from multiple support schemes such as renewable portfolio standards (RPS), feed-in-tariffs (FIT), and market premia (MP). While research concentrated on comparing the effectiveness of these policy instruments in driving RES investment, the focus is increasingly sh...

Rising feed-in from renewable energy sources decreases margins, load factors, and thereby profitability of conventional generation in several electricity markets around the world. At the same time, conventional generation is still needed to ensure security of electricity supply. Therefore, capacity markets are currently being widely discussed as a...

We present a multi-feature stochastic dynamic capacity investment model that includes realistic investor behavior. The long-term investment model includes features, such as strategic bidding of generators, price elasticity of demand, and ramping constraints. It incorporates an iterative procedure of finding a sensible electricity price forecast clo...

Renewable portfolio standards, feed-in-tariffs, and market premia are widely used policy instruments to promote investments in renewable energy sources. Regulators continuously evaluate these instruments along the main electricity policy objectives of affordability, reliability, and sustainability. We develop a quantitative approach to assess these...

School feeding is an established development aid intervention with multiple objectives including education, nutrition, and value transfer. Traditionally run by international organizations in low-income settings, school feeding programs have had a substantial impact in many less-developed countries. However, recent rethinking by the World Bank and t...

The research has the objective to analyse the definition of key terms of the supply chain risk management (SCRM) literature, reflect them with the perspective of managers in the case study company and to lay a foundation for further research. Definitions of the terms ‘risk’, ‘supply chain risk’, ‘supply chain management’, ‘risk management’ and ‘ SC...

Companies rely heavily on the performance of their supply networks. This makes it crucial to source from the best suppliers and to constantly monitor supplier performance during collaboration. Supplier ranking therefore plays an important role, as it consolidates various input variables to capture expected risk or performance. Given the existence o...

In this paper we assess the impact of the CO2 costs for short- and long-haul aircraft based on present values and on purchase options. We evaluate purchase options with a framework developed for real option analysis to estimate the value of flexibility under uncertain kerosene and CO2 prices. We find an average influence of CO2 costs on present val...

We assess the effect of capacity payments on investments in gas-fired power plants in the presence of different degrees of renewable energy technology (RET) penetration. Low variable cost renewables increasingly make investments in gas-fired generation unprofitable. At the same time, growing feed-in from intermittent RETs amplifies fluctuations in...

Feed-in-tariffs (FITs) are widely used as policy instruments to promote investments in renewable energy sources (RES). While FITs are often regarded the most effective RES support scheme, regulators around the world continuously review their FIT schemes in the light of budget constraints and evolving policy goals. We assess the impact of adjustment...

Paul Kleindorfer was among the first to weigh-in on and help nurture the stream of Sustainable Operations Management. The thoughts laid out here are based on conversations that we had with Paul relating to the foundational drivers underlying Sustainability as a management issue-population and per capita consumption growth; the limited nature of res...

We develop a fuel surcharge model for air transport in relation to kerosene and CO2. Price increases, however, induce demand reactions, which in turn may affect profitability. We incorporate demand reactions in our model to calculate an optimal kerosene and CO2 surcharge. We use a numerical example for an illustrative airline network and show that...

This paper presents a real options approach for valuing public-sector research and development projects, using a down-and-out barrier option. Specifically, it considers the potential savings to the tax payer for investing in technology to be purchased by a national government. The valuation is performed with stretched trinomial lattices. Government...

We present a queuing theory based macroscopic traffic flow modeling framework for private and commercial vehicular traffic in emerging market megacities (EMMCs). Road infrastructure is modeled as a large-scale M/G/C/C state-dependent queuing network with Markov modulated service processes to account for structural congestion formation, i.e. congest...

We present a large-scale static, deterministic mixed integer linear programming (MIP) model solving a two-echelon capacitated location routing problem (2E-CLRP) with modal choice in the context of Urban Logistics Services (ULS). The model supports the strategic decision making of postal operators (POs) in designing an optimal facility network and v...

Batteries are responsible for the major share of costs of electric vehicles (EVs). However, they are idle most of the time during vehicle use and expected to retain a significant capacity when discarded from vehicle use. As a result, they may provide an additional value during and after their vehicle life, helping to reduce their total costs of own...

Full-service repair contracts are becoming increasingly popular, especially as an add-on to leasing contracts for technical investment products. This paper presents a model for pricing full-service repair contracts in the presence of risk-averse customers. The model identifies the optimal portfolio of full-service contracts and on-call service agre...

We provide a decision model for La Poste, the French national postal operator, to address its adoption of electric vehicles (EVs) for mail and parcel distribution. Two competing technologies are available—internal combustion vehicles (ICVs) and EVs. We consider uncertainty about future fuel price and future EV battery costs. Within this framework,...

Investitionsentscheidungen gehören fraglos zu den wichtigsten unternehmerischen Aktivitäten; als Beispiele seien genannt die Konstruktion von Produktionsstätten, Errichtung des Maschinenparks oder das Anlegen eines Warenlagers eines Einzelhändlers. In jedem Fall werden Mittel aufgewandt, in der Erwartung zukünftiger Erlöse. Die meisten Investitions...

In today’s world economy, which is marked by increasing international trade, air cargo acts as a key facilitator. However, cargo airlines continue to struggle to be profitable because of very high asset costs and substantial demand uncertainty. To improve upon this situation, we propose an options contract. Our model captures the main features of c...

Share a warehouse… with a competitor? Once it would have seemed unthinkable. Not any more. Transport costs, environmental factors and supply chain logistics are changing the game.

This chapter represents the core of the present analysis. Its purpose is laying the foundations of a market model consisting of a sequence of the following market sessions: a contract market, where capacity can be reserved, and a spot market, where capacity can be purchased on a short-term basis. We explicitly model both the buy and the sell side o...

We review developments in fundamental research on coordination in supply chain management. The review presents recent articles in the field and explicitly addresses new trends in supply chain management, namely, the consideration of multi-tier value-added processes, the coordination of multi-sourcing/customer relationships and the handling of compl...

Options contracts can provide trading partners with enhanced flexibility to respond to uncertain market conditions and allow for superior capacity planning thanks to early information on future demand. We develop an analytical framework to value options on capacity for production of non-storable goods or dated services. The market consists of a seq...

Risk Management is still relatively new to Operations Management (OM), but of ever increasing importance given new legislation such as Basel II. The consideration of risk in operations recently led to the emergence of a research interface between OM and Finance. The present article reviews the evolution of the literature on supply contracts towards...

We develop an analytical framework for the valuation of options contracts for physical delivery that enable risk-sharing between the trading partners. The spot market price risk, the buyer's demand risk and the seller's marginal cost risk, which are key to many industrial settings such as the chemical industry, are explicitly incorporated. Analytic...