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Mustafee, Navonil; Harper, Alison, Viana, Joe & Monks, Thomas
(2025)
A Maturity Model for Digital Twins in Healthcare
Show summary
Digital models, digital shadows, and digital twins (DTs) are increasingly used in manufacturing/Industry 4.0 to represent levels of integration between physical systems and their digital counterparts; data-flow mechanisms are the enablers of such integration. Healthcare operations management has also witnessed rising interest in hybrid models that use real-time data to increase situational awareness (SA) and enable short-term decision-making. In M&S literature, such models are referred to as Real-time Simulations (RtS) and DTs. Healthcare organizations can realize a heightened state of SA by transitioning from conventional modeling to RtS/DTs. The paper presents a Maturity Model for DTs to contextualize the increasing levels of healthcare Information Systems/Information Technology (IS/IT) integration with real-time models that such a shift will necessitate. The higher the Maturity Level of IS/IT integration, the greater the opportunity to develop modeling artifacts that realize the potential of real-time data and enable organizations to attain higher levels of SA.
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Jambor, Elisabeth; Viana, Joe, Reuter-Oppermann, Melanie & Müller-Polyzou, Ralf
(2025)
Evaluating the impact of COVID-19 protection measures and staff absence on radiotherapy practice: A simulation study
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Hope, Ole-Kristian; Lu, Haihao & Peng, Songlan
(2025)
Economic Consequences of AS 18: Related-Party Transactions with Principals versus Nonprincipals
Show summary
In 2014, the PCAOB adopted a new auditing standard, AS 18 Related Parties, with the intention of enhancing auditors’ performance in auditing related-party transactions (RPTs). Using hand-collected data, we find significant reductions in both firms’ restatement risk and their engagement in RPTs following the AS 18 adoption. Such reductions are especially pronounced for smaller firms and firms having RPTs with principals, in which related persons in the counterparty of RPTs are the primary beneficiaries, such as CEOs, board chairs, or primary shareholders. We also find that smaller firms having RPTs with principals tend to pay higher audit fees post-AS 18. Our study responds to the PCAOB’s call to assess the economic consequences of AS 18. The findings suggest that AS 18 is associated with improved audit quality and reductions in auditees’ opportunistic RPT activities.
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Knardal, Per Ståle & Landrø, Karsten
(2025)
Foreldremedvirkning i kulturskolen. Samproduksjon i praksis
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Khalilov, Akram; Gazizova, Irina & Osma, Beatriz Garcia
(2025)
Directors' Bankruptcy Experience and Financial Reporting Choices
Show summary
We identify directors who experience a corporate bankruptcy and examine how this professional experience affects monitoring at the other firms where they concurrently sit on the board. Using a sample of US directors interlocked with firms that file for bankruptcy, we find that directors have a greater tolerance for real earnings management after a low-cost bankruptcy experience. This effect is stronger for independent directors and those who sit on the audit committee, consistent with a ratification and monitoring explanation. We do not find evidence consistent with the competing hypotheses that bankruptcy leads to directors' distraction or incentivizes efficient cost-cutting strategies. We contribute to the research on the influence of directors' corporate experience over corporate outcomes, by providing evidence suggesting that surviving a bankruptcy relatively unscathed lowers directors' perception of the severity of distress costs, with negative consequences for decision control.
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Correia-Duarte, Pedro Josè; Dauzère-Pérès, Stéphane, Huisman, Dennis, Mannino, Carlo, Sartor, Giorgio & Weik, Norman
(2025)
50 years of OR in railway timetabling and rolling stock planning
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Melaku, Tsegaye; Mekonnen, Zeleke, Tucho, Gudina Terefe, Viana, Joe, Årdal, Christine Oline & Jahre, Marianne
(2025)
Resilience and Adaptability in Paracetamol Supply Chains: A Systems Perspective on COVID-19 Challenges and Responses in Ethiopia
Show summary
Background: The COVID-19 pandemic exposed vulnerabilities in global supply chains, including those for essential medicines like paracetamol. This study aimed to assess the resilience and adaptability of Ethiopia’s paracetamol supply chain during the pandemic. Methods: A mixed-methods approach was employed, combining semi-structured interviews with key stakeholders and analysis of secondary data on paracetamol availability and supply chain disruptions. The study employed systems thinking and supply chain resilience frameworks, utilizing causal loop diagrams to visualize system dynamics. Results: Eighteen stakeholders, representing seven pharmaceutical manufacturers, five import companies, and five wholesalers, participated in the study. These participants had between three and fourteen years of experience in their respective roles. The study revealed complex interactions within the paracetamol supply chain, highlighting both challenges and adaptive responses. While 500 mg paracetamol tablets were readily available, shortages of other formulations were observed due to a range of factors, including limited product diversification, political instability, inflation, and reduced production efficiency. Conclusions: The resilience and adaptability of stakeholders, particularly manufacturers and importers, were crucial in maintaining the supply of 500 mg paracetamol tablets. Key strategies included regional sourcing, increased production, and improved partnerships. Understanding the interconnectedness of factors within the supply chain is essential for developing effective strategies to enhance its resilience and ensure sustained access to paracetamol in the future.
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Khalilov, Akram
(2025)
Informational and cushioning properties of conservative balance sheets: a study of crises resilience
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This study examines the informational and cushioning properties of balance sheet conservatism (BSC) and their role in mitigating the adverse effects of financial crises. I document that, due to informational property, high-BSC firms raise more debt and have a lower cost of debt financing during the crisis. The cushioning property of BSC is associated with lower earnings volatility, likelihood of significant asset write-downs and probability of covenant violations. These properties contribute to superior performance, including smaller declines in stock prices, investment, employment, and productivity. An out-of-sample test using the setting of the Great Depression (1929–1933) confirms the aforementioned findings. Overall, a path analysis suggests that BSC effects operate mostly through cushioning (informational) property contributing 39% (11%) to overall firms’ performance during the crisis.
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Bø, Eirill & Baxter, John
(2025)
Sustainability of the Collection of Norwegian Household Waste
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Viana, Joe; Vasilakis, Christos & Stylianou, Neophytos
(2025)
Leveraging quality improvement initiatives to support development of decision support tools in healthcare
Show summary
Modelling and simulation studies have been used to inform the choices and development of quality improvement (QI) initiatives in health care, for example, by helping refine the intervention to be implemented or support decisions around the management of demand and capacity. We do not know whether a modelling study can itself be informed by a QI project and what are the associated benefits and challenges. In this research, we sought to investigate the opportunities and challenges associated with an ongoing health service-led QI project in informing the development of a stochastic simulation-based decision support tool to inform decisions around the commissioning of anticoagulation services for patients with atrial fibrillation. We found that the positive synergies offered by the QI project included good access to stakeholders and envisaged end users, co-producing relevant and impactful scenarios for experimentation, as well as access to good quality individual patient level data. On the other hand, substantial effort was required to populate input parameters with values that pertain to the natural history of the disease and the effectiveness of the different treatments. Our findings indicate that, if stakeholders require modelling results to inform aspects of a QI project, upfront investment is needed to ensure timely interaction between the two studies.
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Huemer, Lars & Flygansvær, Bente Merete
(2025)
Increasing circularity: The importance of resource interactions when adapting from waste management to resource management
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Corral de Zubielqui, Graciela & Steen, Riana
(2024)
The Impact of Adaptation on Performance Through Business Resilience in Times of Crisis
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Ruud, Flemming; Schreyer, Marco, Borth, Damian & Vasarhelyia, Miklas
(2024)
A Sum Greater Than Its Parts: Collaborative Artificial Intelligence in Auditing
Advancing Audit Models through Federated Learning of Without Sharing Proprietary Data
Expert Focus, 98(4), p. 180-186.
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Andvik, Elisabeth; Egeland, Therese, Schei, Vidar & Andvik, Christian
(2024)
Escaping the Professional Identity “Straitjacket”: Towards a Model of Identity Plasticity
Proceedings and Membership Directory - Academy of Management.
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van Oorschot, Kim E.; Johansen, Vilde Aas, Thorup, Nanna Lynes & Aspen, Dina Margrethe
(2024)
Standardization cycles in sustainability reporting within the Global Reporting Initiative
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Wang, Yue; Liu, Ming, Viana, Joe & Dube, Nonhlanhla
(2024)
How to improve the quality of emergency supplies? A tripartite evolutionary game model
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Bleibtreu, Christopher; Erinc, Mert, Orozco, Luciana & Shi, Zhenyang
(2024)
Auditors and client investment efficiency: a quasi-replication and further insights from a regulatory change
Show summary
This study is a quasi-replication and extension of Bae et al. (Account Rev 92(2):19–
40, 2017), which examines the relationship between auditors’ characteristics and
their audit clients’ investment efficiency. Whereas Bae et al. (Account Rev 92(2):19–40, 2017) use U.S. public firm data, we draw a more general picture by using both public and private firm data from Norway. Overall, the results for Norwegian public and private firms are in line with those Bae et al. (Account Rev 92(2):19–40, 2017) find for public U.S. firms. That is, audit clients invest more efficiently if their auditors have more knowledge and resources, measured by auditor market shares or whether a Big N audit firm performs the audit. Further, an auditor’s influence on its client’s investment efficiency is more pronounced when clients have a higher demand for information, proxied by client complexity. Finally, exploiting a regulatory change in 2011 that allowed small private Norwegian firms to opt out of previously mandatory auditing, we extend the study by Bae et al. (Account Rev 92(2):19–40, 2017). We find that audits can increase investment efficiency for small private firms. Specifically, firms that dismiss their auditors tend to overinvest more than similar firms that are not eligible to opt out of auditing. Further, firms that voluntarily keep their auditor have an overall higher investment efficiency than similar firms that are not audited.
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Ciconte, William A.; Leiby, Justin & Willekens, Marleen
(2024)
Where Does the Time Go? Auditors’ Commercial Effort, Professional Effort, and Audit Quality
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Melaku, Tsegaye; Mekonnen, Zeleke, Terefe Tucho, Gudina, Mecha, Mohammed, Årdal, Christine Oline & Jahre, Marianne
(2024)
Availability of essential, generic medicines before and during COVID-19 at selected public pharmaceutical supply agencies in Ethiopia: a comparative cross-sectional study
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Cai, Hong; Hope, Ole-Kristian, Li, Yi, Liu, Qiliang & Wu, Han
(2024)
The (In)Visibility of Undisclosed Political Connections
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Despite a strong investor and social demand for firms to disclose information on political connections, mandatory disclosure requirements face considerable opposition. Given the challenges in enforcing mandatory disclosures, we investigate whether private information acquisition can be a viable alternative to disclosure. Using a setting of corruption investigations, we find that investors, on average, are not aware that the firms they have invested in have connections with the officials under investigation, suggesting a lack of visibility of the connections. However, a small number of institutional investors exploit their private access to information and sell their shares in response to the investigations. We also show that the high costs of information acquisition and a lack of incentives for analysts to disseminate sensitive information they have obtained contribute to this lack of visibility and result in a significant delay in retail investors’ reaction to material information. Our study contributes to the debate on mandating disclosure of political connections by showing that the lack of mandatory disclosure results in an uneven playing field that undermines transparency and fairness.
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Cantelmi, Raffaele; Steen, Riana, Di gravio, Giulio & Patriarca, Riccardo
(2024)
An explorative Bayesian analysis of functional dependencies in emergency management systems
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Torba, Rahman; Dauzère-Pérès, Stéphane, Yugma, Claude, Gallais, Cédric & Pouzet, Juliette
(2024)
Solving a real-life multi-skill resource-constrained multi-project scheduling problem
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Knardal, Per Ståle
(2024)
Packing and unpacking management control in major sport events
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Steen, Riana; Roud, Ensieh , Mikkelrud Torp, Trude & Hansen, Thor-Arild
(2024)
The impact of interorganizational collaboration on the viability of disaster response operations: The Gjerdrum landslide in Norway
Show summary
This study investigates the interorganizational collaboration among agencies that responded to a landslide in Gjerdrum, Norway in 2020. It focuses on the crucial role of communication, coordination, cooperation, and knowledge sharing within organizations, and it examines tensions between centralization and decentralization, professional and administrative leadership, planning and improvisation, and external and internal information sharing. To explore this collaboration, we conducted nine interviews and employed the viable system model (VSM) as a conceptual and methodological framework. Through a systemic diagnosis of the search and rescue (SAR) crisis response system’s viability and by applying the VSM, the structural, communicational, and functional pathologies in interorganizational collaboration were identified. Thus, this diagnostic approach allowed us to determine the pathological features that challenged the SAR system’s effectiveness and viability, including imbalances, inefficiencies in maintaining internal and external interactions, communication breakdowns, and inefficient resource allocation. These insights clarify the structural challenges within the SAR system and underscore the significance of optimizing interconnections, establishing efficient decision-making processes, and improving communication flows to enhance the overall effectiveness of the SAR system.
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Hovi, Inger Beate & Bø, Eirill
(2024)
Unlocking the potential: How can parcel lockers drive efficiency and environmental friendliness in E-commerce?
Show summary
This paper analyses the efficiency and carbon footprint of different last-mile delivery solutions, including parcel lockers, pick-up points, and home deliveries. A Decision Support Tool (DST) is developed, utilizing real data on parcel deliveries and time allocation. The DST distinguishes between fixed, variable, and salary costs, revealing that time spent on delivery tasks and associated salary costs are the primary cost drivers. Deliveries to pick-up points are more efficient than deliveries to parcel lockers, but this efficiency depends on the number of parcels delivered. The environmental footprint of the solutions is influenced by how recipients collect their parcels.
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Steen, Riana; Norman, James, Bergström, Johan & Damm, Gitte F.
(2024)
Dark knights: Exploring resilience and hidden workarounds in commercial aviation through mixed methods
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Kramer, Michael Paul; Viana, Joe, Mueller, Rolf A. E., Hanf, Claus-Henning & Hanf, Jon H
(2024)
Towards a taxonomy of multi-agent simulation models to determine disruptive technology adoption behaviour in the wine industry
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Lyngstadås, Hakim & Mauritzen, Johannes
(2024)
Adults in the room? The auditor and dividends in small firms: evidence from a natural experiment
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Dube, Nonhlanhla; Selviaridis, Kostas, van Oorschot, Kim E. & Jahre, Marianne
(2024)
Riding the waves of uncertainty: Towards strategic agility in medicine supply systems
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Orozco, Luciana & Rubio, Silvina
(2024)
Regulatory Capital Management to Exceed Thresholds
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Hope, Ole-Kristian; Wang, Cyndia, Wu, Yaqian & Zhang, Min
(2024)
Does Convergence with International Standards on Auditing Improve Audit Quality?
Show summary
Many countries have converged their domestic auditing standards with International Standards on Auditing (ISA). This study provides global empirical evidence on first-order determinants of audit quality by examining whether and how convergence affects audit quality through utilizing data on 41 jurisdictions and using a staggered difference-in-differences approach. We find that ISA convergence leads to higher audit quality on average. The positive effect is stronger for clients of domestic audit firms, in jurisdictions with stronger enforcement, and when the ISA convergence level is higher. Insights from textual features suggest that changes in principle-orientation, comparability, readability, and size (or length) of auditing standards are positively related to audit quality. Exploratory analyses of textual content using machine learning reveal that the emphases of ISA on going-concern assessment and legal compliance, fraud risk assessment and internal control evaluation, and related-party transactions and su
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Chen, Zhihong; Hope, Ole-Kristian, Li, Qingyuan & Li, Yongbo
(2024)
Offshore activities and corporate tax avoidance
Show summary
We investigate the relation between tax avoidance and offshore activities using a new text-based measure for offshore activities based on Hoberg and Moon (2017, 2019). Our evidence shows that, although providing cross-border tax-avoidance opportunities, offshore activities reduce the marginal benefits of tax avoidance by introducing incremental foreign-market risk exposure. We find that the intensity of offshore sales of outputs is positively associated with the cash effective tax rate. The effect is stronger when the offshore sales rely on overseas production rather than domestic production, when the offshore sales are located in countries with higher economic uncertainty, when the firm has a lower ability to pass on shocks, and when the firm has less flexibility in adjusting tax strategies.
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Penn, Marion & Viana, Joe
(2024)
Infant care transfers: simulating neonatal infant pathways and transfers across a neonatal network
Show summary
Neonatal care for preterm and sick babies is organised into local areas around the United Kingdom, called Operational Delivery Networks. These networks coordinate between providers to ensure babies have the required care, close to home. There are three types of Neonatal Units offering distinct levels of needs-based care. The networks need to ensure that each unit operates at optimal cot levels, and the best quality care is provided. The possible impact of any changes to a network’s configuration on transfers and infant care, must be considered before any changes are implemented. Our simulation model reflects the infant pathways within a network allowing users to evaluate a variety of possible changes within the network. The model builds on previous literature by incorporating the ability to move an existing infant from a unit to release capacity as well as moving new arrivals between units. We also consider the potential environmental impact of the additional travel for parents visiting infants who have been transferred. We demonstrate how the model can be applied with a case network within which approximately 60,000 babies are born annually, a tenth of whom requiring some Neonatal Care. Of these infants, approximately 12% are transferred to another unit.
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Ding, Wenhong; Guan, Wei, Ke, Yun, Olsen, Kari Joseph & Shi, Zhenyang
(2024)
Local CEOs and asymmetric cost behaviour
Show summary
We examine the effect of a local CEO (i.e., the CEO's state of origin is the same as his/her firm's headquarter states) on a firm's strategic capacity choices and the resulting cost asymmetry. We find that firms with local CEOs demonstrate greater cost asymmetry. Place attachment, local advantage and agency cost theory could all influence a firm's cost asymmetry. To differentiate between these explanations, we use a consequence test that examines the association between asymmetric costs and future performance. Our results indicate that the greater cost asymmetry in firms with local CEOs is associated with higher future firm value, which suggests that the greater cost asymmetry from local CEOs arises due more to a local advantage. We include several cross-sectional tests to explore when this result is more or less pronounced. Our results suggest that geographically segmented labour markets play an important role in a firm's resource capacity decisions.
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Flygansvær, Bente Merete & Dahlstrøm, Robert
(2024)
Enhancing circular supply chains via ecological packaging: An empirical investigation of an extended producer responsibility network
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Yang, Wei-Ting; Tamssaouet, Karim & Dauzère-Pérès, Stéphane
(2024)
Bayesian network structure learning using scatter search
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Kornberger, Martin; Schott, Clarissa Ruth Marie, Knudsen, Dan-Richard & Andvik, Christian
(2024)
Mapping data-driven management in accounting: the premise and promise of the debate and how to move beyond
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Steen, Riana & Hansen, Tommy B.
(2024)
Collaborative defense in the Arctic: Strengthening Norway's oil sector resilience through knowledge sharing and vigilance against drone threats
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Absi, Nabil; van den Heuvel, Wilco & Dauzère-Pérès, Stéphane
(2024)
Complexity analysis of integrated dynamic lot sizing and maintenance planning problems
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Rasmussen, Janicke; Knutsen, Jovana & Arnulf, Jan Ketil
(2024)
Styrer og bærekraft: Norske børsnoterte selskap møter forventninger med kontroll heller enn strategi
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Knutsen, Jovana & Arnulf, Jan Ketil
(2024)
Styrer og bærekraft: Norske børsnoterte selskap møter forvetninger med kontroll heller enn strategi
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Lyngstadås, Hakim & Berg, Terje
(2024)
The C-Suite of Supplier Collaboration: A Configurational Analysis of the How’s and Why’s.
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Fiechter, Peter; Landsman, Wayne, Peasnell, Ken & Renders, Annelies
(2023)
Do industry-specific accounting standards matter for capital allocation decisions?
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Anchev, Stefan & Lapanan, Nicha
(2023)
Investor Base Size and Underreaction-Consistent Stock Return Anomalies
Show summary
We find that several well-documented underreaction-consistent stock return anomalies, such as those based on stocks' earnings-to-price ratios, returns on assets and past returns, arise and persist only among stocks with smaller (institutional) investor bases, which are presumably stocks that are neglected by investors. These results are driven by the short side of our long-short trading strategies (i.e., by the seemingly overpriced stocks from the bottom quantiles of the anomaly variables), they appear even after controlling for several stock characteristics (e.g., market capitalization and institutional ownership) and potential risk factors, and they are considerably more pronounced during periods with more information and/or less technology. Overall, these findings suggest that the incomplete dissemination of (negative) information across investors helps in explaining the occurrence and the persistence of the anomalies.
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Mustafee, Navonil; Viana, Joe & Harper, Alison
(2023)
Hybrid Models with Real-Time Data in Healthcare: A Focus on Data Synchronization and Experimentation
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Hope, Ole-Kristian; Porumb, Vlad-Andrei, Rusanescu, Simona & Vyas, Dushyantkumar
(2023)
Private information and bank-loan pricing: The effectof upcoming corporate spinoffs
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Liu, Junhao; Hope, Ole-Kristian & Hu, Danqi
(2023)
Earnings announcements in China: Overnight-intraday disparity
Show summary
Based on a unique arrangement of trading and disclosure times around earnings announcements in the Chinese stock market, we provide evidence of a striking overnight-intraday disparity in terms of the reaction to earnings news. Specifically, we find that the overnight period exhibits a strong and consistent reaction to earnings announcements, whereas the intraday period trades against both the earnings news and the prior market reaction during the overnight period. In addition, we show that abnormal overnight returns on earnings announcement days exhibit strong predictability for future stock returns, consistent with the overnight returns containing value-relevant signals. In contrast, we observe no return predictability for abnormal intraday returns on earnings announcement days, which as a result, also undermines the return predictability of abnormal daily returns. We propose possible explanations for the overnight-intraday disparity. We conclude that the differences in trading mechanisms between the two periods as well as in investor composition likely drive the phenomenon.
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Pruijssers, Jorien; Simac, Ines & Willekens, Marleen
(2023)
Strength of Audit Firms’ Human Resource Systems and Client-Level Audit Outcomes: Evidence from a Multiple Source Study
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Steen, Riana; Haug, Ole Jacob & Patriarca, Riccardo
(2023)
Business continuity and resilience management: A conceptual framework
Show summary
The overall objective of business continuity management (BCM) systems is to provide guidance and analytical subcomponents on how to assess and manage risk and sustain operations when facing a disruptive event. Current BCM practices largely follow a standard structure for formal planning processes and risk-assessment activities. An underlying assumption in standard practices is that systems can be decomposed in subsystems in a meaningful way, as they are tractable and data are available to predict the system's future functionality. However, the reality is much more complex in our volatile world. Standard BCM approaches do not pay adequate attention to the treatment of uncertainties. Thus, they fall short of addressing the complexity of operations involved with emergencies and crisis. Lack of focus on uncertainty hampers the ability of BCM systems to provide sufficient support for decision making in highly uncertain situations. Dealing with such situations necessitates a shift from a defensive risk-management approach, grounded on an illusion of control and accountability, to a proactive stance based on resilience thinking. Responding to this call, we use concepts from the resilience engineering (RE) field and link them to different components of a BCM system. We develop a novel BCM framework and identify a set of resilience influence factors to enhance resilience in BCM systems. We use a case-example, hosted by a leading organization in a second-line emergency response operation in Norway to reflect on the application of a suggested BCM framework.
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Steen, Riana; Håheim-Saers, Nils & Aukland, Gina
(2023)
Military unmanned aerial vehicle operations through the lens of a high-reliability system: Challenges and opportunities
Show summary
This study examines the impact of regulations and standard procedures on safety outcomes in unmanned aerial vehicle (UAV) operations, specifically focussing on Norwegian military UAV systems, from a high-reliability organization (HRO) perspective. By analyzing data from existing regulations, accident reports, and interviews with military drone pilots using thematic analysis, we identify key recurring themes. Our findings highlight the importance of fatigue and exhaustion due to the absence of regulations on resting time for military drone pilots. This poses substantial risks and increases the likelihood of accidents and incidents in UAV operations. Additionally, we uncover gaps in safety reporting and accountability for military UAV pilots, indicating the need for improved reporting procedures that consider the unique operational elements of UAVs. Effective communication between stakeholders, including drone pilots, ground crew, and air traffic controllers, emerges as a critical factor in maintaining situational awareness. This emphasis on communication is consistent with HRO principles and supports the essential safety tasks of UAV pilots, namely sense-making, decision making, and performance. By uncovering the impact of regulations and operational procedures on safety outcomes and addressing fatigue in UAV operations, this research contributes to enhancing the safety and reliability of Norwegian military UAV systems.
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Tamssaouet, Karim & Dauzère-Pérès, Stéphane
(2023)
A general efficient neighborhood structure framework for the job-shop and flexible job-shop scheduling problems
Show summary
This article introduces a framework that unifies and generalizes well-known literature results related to local search for the job-shop and flexible job-shop scheduling problems. In addition to the choice of the metaheuristic and the neighborhood structure, the success of most of the influential local search approaches relies on the ability to quickly and efficiently rule out infeasible moves and evaluate the quality of the feasible neighbors. Hence, the proposed framework focuses on the feasibility and quality evaluation of a general move when solving the job-shop and flexible job-shop scheduling problems for any regular objective function. The proposed framework is valid for any scheduling problem where the defined neighborhood structure is appropriate, and each solution to the problem can be modeled with a directed acyclic graph with {non-negative weights on nodes and arcs}. The feasibility conditions and quality estimation procedures proposed in the literature rely heavily on information on the existence of a path between two nodes. Thus, based on an original parameterized algorithm that asserts the existence of a path between two nodes, novel generic procedures to evaluate the feasibility of a move and estimate the value of any regular objective function of a neighbor solution are proposed. We show that many well-known literature results are special cases of our results, which can be applied to a wide range of shop scheduling problems.
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Shen, Liji; Dauzère-Pérès, Stéphane & Maecker, Söhnke
(2023)
Energy cost efficient scheduling in flexible job-shop manufacturing systems
Show summary
This paper studies the problem of determining energy efficient schedules in a flexible job shop. The goal is to minimize the total energy cost, given a time-of-use pricing scheme, while ensuring that the schedule does not violate a maximum makespan. The problem is first formalized as a mixed integer program. Because it is already difficult to solve, the simpler problem with a fixed sequence of operations is then extensively studied. Some properties are derived for the specific problem with a fixed sequence. These properties show that the complexity of the problem depends on the structure of the energy pricing scheme. They are also used to propose two heuristic approaches. Relying on these heuristics, we further develop an iterative tabu search for the general problem. Extensive computational experiments are carried out to evaluate the solution methods and the potential gains on the total energy cost, depending on the flexibility associated to the maximum allowed makespan and on the time-of-use structures.
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Arnulf, Jan Ketil; Rasmussen, Janicke, Hjersing, Sandra & Berner, Thea
(2023)
CEO dismissal as an act of human sacrifice: Metaphor or reality?
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Zuiderwijk, Dianka; Steen, Riana & Pedro, Ferreira
(2023)
Learning from Operational planning
Show summary
Institutional and regulatory approaches to planning are still primarily based on linearity and predictability and show a trend towards centralised control and prescriptive planning. A second trend recognises unpredictability in complex operations and focuses on dealing with the changeable nature of work. We refer to this adaptive type of planning as operational planning (OP). In this paper, we argue that a shift towards more control and prescriptive planning can undermine this critical adaptive capability in the completion of complex operations. Triggered by lessons drawn from three different studies, we demonstrate that fostering this adaptive capability in complex operations necessitates a shift in how uncertainty is addressed in institutional and regulatory systems. While exploratory, our findings add to a more complete picture of OP and its relevance to the reliability of complex operations.
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Wood, David A.; Kulset, Ellen Hiorth Marthinsen, Kuruppu, Gowindage Chamara Jayanath, Lyngstadås, Hakim, Madsen, Dag Øivind, Sundkvist, Charlotte Haugland, Allee, Kristian D., Allen, Abigail M., Almer, Elizabeth D., Ames, Daniel, Arity, Viktor, Achhpilia, Muskan, Barr-Pulliam, Dereck, Basoglu, K. Asli, Belnap, Andrew, Bentley, Jeremiah W., Berglund, Nathan R., Berry, Erica, Bhandari, Avishek, Bhuyan, Md Nazmul Hasan, Black, Paul W., Blondeel, Eva, Adams, Mollie T., Bond, David, Bonrath, Annika, Borthick, A. Faye, Boyle, Erik S., Bradford, Marianne, Brandon, Duane M., Brazel, Joseph F., Brockbank, Bryan G., Burger, Marcus, Byzalov, Dmitri, Aghazadeh, Sanaz, Cannon, James N., Caro, Cecil, Carr, Abraham H., Cathey, Jack, Cating, Ryan, Charron, Kimberly, Chavez, Stacy, Chen, Jason, Chen, Jennifer C., Chen, Jennifer W., Akinyele, Kazeem, Cheng, Christine, Wright, Nicole S., Woolley, Darryl, Wood, Jessica, Wood, Bryan D., Witte, Annie L., Wiseman, Denise, Winrow, Tasia S., Winrow, Timothy, Winrow, Brian, Akpan, Mfon, Berg, Terje, Heinzelmann, Rafael & Johanson, Bjørn Daniel
(2023)
The ChatGPT artificial intelligence chatbot: How well does it answer accounting assessment questions?
Show summary
ChatGPT, a language-learning model chatbot, has garnered considerable attention for its ability to respond to users’ questions. Using data from 14 countries and 186 institutions, we compare ChatGPT and student performance for 28,085 questions from accounting assessments and textbook test banks. As of January 2023, ChatGPT provides correct answers for 56.5 percent of questions and partially correct answers for an additional 9.4 percent of questions. When considering point values for questions, students significantly outperform ChatGPT with a 76.7 percent average on assessments compared to 47.5 percent for ChatGPT if no partial credit is awarded and 56.5 percent if partial credit is awarded. Still, ChatGPT performs better than the student average for 15.8 percent of assessments when we include partial credit. We provide evidence of how ChatGPT performs on different question types, accounting topics, class levels, open/closed assessments, and test bank questions. We also discuss implications for accounting education and research.
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Hormozi, Mohammad Ali; Zaki Dizaji, Hassan, Bahrami, Hoshang, Sharifyazdi, Mehdi & Monjazi, Nasim
(2023)
Multi-objective optimization of allocating sustainable mechanization for spraying and harvesting systems in paddy fields
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Flores-Gómez, Mario; Borodin, Valeria & Dauzère-Pérès, Stéphane
(2023)
Maximizing the service level on the makespan in the stochastic flexible job-shop scheduling problem
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This paper considers the flexible job-shop scheduling problem with stochastic processing times. To find a sequence insensitive to shop floor disturbances, the available probabilistic information related to the variability of processing times is taken into account by maximizing the makespan service level for a given deadline. This corresponds to the probability of the makespan to be smaller than a given threshold. After showing why this criterion makes sense compared to minimizing the average makespan, a solution approach relying on a tabu search and a Monte Carlo sampling-based approximation is presented. Then, new instances are generated by extending the deterministic benchmark instances. Extensive computational experiments are conducted to evaluate the relevance of the makespan service level and the performance of the proposed solution method. The drawbacks of a number of reference scenarios, including worst-case and best-case scenarios, in addressing effectively the problem under study are presented. A numerical analysis is also performed to compare the scope of the proposed criterion against the minimization of the expected makespan. The accuracy of the proposed solutions induced by the hyper-parameters of the Monte Carlo approximation is explicitly analyzed.
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Mustafee, Navonil; Harper, Alison & Viana, Joe
(2023)
Hybrid Models with Real-time Data: Characterising Real-time Simulation and Digital Twins
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Real-time Simulation (RtS) and Digital Twins (DT) are terms generally associated with hybrid models
that use real-time data to drive computational models. Additionally, in the case of DTs, real-time data
is often used to create virtual replicas of the physical system as it progresses through real-time. There
is an increasing volume of literature on RtS and DT; however, the field of OR/MS is yet to coalesce on
accepted definitions and conceptualisations. This has arguably led to the cascading usage of these terms.
The objective of the paper is threefold: (1) distinguish between RtS and DT, (2) present RtS-DT
conceptualisation in four dimensions, and (3) present methodological and technical insights on
developing RtS with limited data. We argue that the evolution of conventional simulation models to
fully-fledged hybrid DTs may necessitate a focus on a transitional stage; namely, RtS models primarily
driven using historical distributions with limited real-time data feeds.
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Chen, Jeff Zeyun; Elemes, Anastasios, Hope, Ole-Kristian & Yoon, Aaron S.
(2023)
Audit-Firm Profitability: Determinants and Implications for Audit Outcomes
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We use a novel dataset that links audit-firm and client-firm financial statement information from the U.K.’s largest audit firms to examine drivers of audit-firm profitability and its implications for audit outcomes. We first explore the determinants of audit-firm profitability and conclude that Big-4 and non-Big-4 audit firms have fundamentally different profitability structures. Big-4 firms have higher profit margins than non-Big-4 firms. Furthermore, Big-4 profitability increases with client size and complexity, while non-Big-4 profitability is higher for smaller, private-firm clients. Next, we examine the relation between audit-firm profitability and audit outcomes. Using a battery of alternative outcome measures, we find that more profitable audit firms deliver higher audit quality. In supplemental analyses we show that the positive relation between audit-firm profitability and audit outcomes is generally stronger for more influential and illiquid clients (i.e. when auditors are exposed to more litigation risk). Our inferences are robust to several endogeneity controls, such as using an instrumental variables approach, controlling for client-firm and audit-firm fixed effects, employing lead-lag and changes specifications, and assessing bias from correlated omitted variables. Our study contributes to the literature by being the first to provide insights into audit-firm profitability and examine in detail its implications for audit quality.
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Rodoplu, Melek; Dauzère-Pérès, Stéphane & Vialletelle, Philippe
(2023)
Integrated planning of maintenance operations and workload allocation
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Motivated by a practical problem, this paper investigates the integrated planning of maintenanceoperations and workload allocation on a set of machines in a workshop. Given quantities of productsto be produced per period on a planning horizon must be processed on unrelated flexible machines.Moreover, each machine has to undergo one or more maintenance operations that must be plannedwithin a given time window and impact products differently. The main goal is to find a feasible planthat satisfies the machine capacity by allocating the production quantities to machines and assign-ing maintenance operations as late as possible in their time windows. Various original mathematicalmodels are presented. In particular, we propose models that allow maintenance operations andsome production quantities to overlap two consecutive periods. Computational experiments basedon industrial data show that allowing this overlapping helps the earliness of maintenance opera-tions to be significantly reduced in the most difficult instances, going for example from a total of 14periods to only 1 period, and by more than 35% on average.
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Chen, Lu; Yang, Wenhui, Qiu, Kejun & Dauzère-Pérès, Stéphane
(2023)
A lexicographic optimization approach for a bi-objective parallel-machine scheduling problem minimizing total quality loss and total tardiness
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In wafer fabrication, production quality is a key performance index and is subject to machine condition deterioration. This paper studies a parallel-machine scheduling problem that can typically be found in the photolithography process. To solve the problem, a lexicographic optimization approach is proposed where the total quality loss is firstly minimized and the second objective is to minimize total tardiness. An optional maintenance activity is also considered to restore the machine condition to a certain level. Optimality properties are discussed, based on which an exact scheduling algorithm is developed. Experimental analyses derived from real data demonstrate the effectiveness of the proposed algorithm and support some managerial insights.
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Kasapidis, Gregory A.; Dauzère-Pérès, Stéphane, Paraskevopoulos, Dimitris C., Repoussis, Panagiotis P. & Tarantilis, Christos D.
(2023)
On the multiresource flexible job-shop scheduling problem with arbitrary precedence graphs
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This paper aims at linking the work presented in Dauzère-Pérès et al. (1998) and more recently in Kasapidis et al. (2021) on the multiresource flexible job-shop scheduling problem with nonlinear routes or equivalently with arbitrary precedence graphs. In particular, we present a mixed integer linear programming (MIP) model and a constraint programming (CP) model to formulate the problem. We also compare the theorems introduced in Dauzère-Pérès et al. (1998) and Kasapidis et al. (2021) and propose a new theorem extension. Computational experiments were conducted to assess the efficiency and effectiveness of all propositions. Lastly, the proposed MIP and CP models are tested on benchmark problems of the literature and comparisons are made with state-of-the-art algorithms.
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Steen, Riana; Haakonsen, Geir & Steiro, Trygve Jakobsen
(2023)
Patterns of Learning: A Systemic Analysis of Emergency Response Operations in the North Sea through the Lens of Resilience Engineering
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Crisis-induced learning (CIL), as a concept, has an ancient history. Although the academic literature offers a range of sophisticated approaches to address CIL, it is still not quite clear how we learn, how we know we have learned, and what challenges and opportunities are involved in the CIL process. To address these questions and navigate ways forward, we need to use a specific real-world subject to capture contextual issues involved in a crisis cycle, which affects the learning process. In this paper, we uncover patterns of learning by exploring contextual issues involved with “actual scenarios” related to three COVID-19 episodes (emergencies) between August and December 2020. To analyze the study’s findings, we use three different themes from the DARWIN Generic Resilience Management Guidelines: (1) supporting the coordination and synchronization of emergency-response operation activities, (2) managing adaptive capacity, and (3) developing and revising procedures and checklists. Looking into these “real scenarios” seems fruitful for understanding patterns of learning, and it results in several learning recommendations. Among others, this study reveals how the uncertainty involved in emergency-response operations creates cognitive demands for emergent problem-solving.
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Tamssaouet, Karim; Engebrethsen, Erna & Dauzère-Pérès, Stéphane
(2023)
Multi-item dynamic lot sizing with multiple transportation modes and item fragmentation
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This paper addresses a tactical joint inventory and transportation planning problem for multiple items with deterministic and time-varying demand, considering different transportation modes and item fragmentation. The latter corresponds to the splitting of the same item ordered quantity between several trucks or containers. On the one hand, fragmenting the items potentially reduces the number of containers used. On the other hand, loading the item lot fragments on several containers may negatively impact the handling and shipping operations. This new problem is proposed as a way to tackle such conflict. Several Mixed Integer Linear Programming models are proposed for the problem, which rely on two multi-item lot-sizing models with mode selection and two bin-packing models with item fragmentation. A relax-and-fix heuristic is also proposed. Using realistic instances, computational experiments are first conducted to identify the most efficient model in terms of computational time, to study the impact of key parameters on the computational complexity and to analyze the efficiency of the heuristic. Then, managerial insights are derived through additional computational experiments, in particular, to identify contexts requiring joint optimization of lot-sizing and bin-packing decisions, as well as the impact of item fragmentation constraints. Directions for future research are finally proposed.
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Berterottière, Lucas; Dauzère-Pérès, Stéphane & Yugma, Claude
(2023)
Flexible job-shop scheduling with transportation resources
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This paper addresses an extension of the flexible job-shop scheduling problem where transportation resources are explicitly considered when moving jobs from one machine to another. Operations should be assigned to and scheduled on machines and vehicles and the routes of vehicles should be determined. We extend the classical disjunctive graph model to include transportation operations and exploit the graph in an integrated approach to solve the problem. We propose a metaheuristic using a neighborhood function that allows a large set of moves to be explored. As the exact computation of the makespan of every move is time-consuming, we present a move evaluation procedure that runs in constant time (which does not depend on the size of the instance) to choose a promising move in the neighborhood of a solution. This move evaluation procedure is used in a tabu search framework. Computational results show the efficiency of the proposed approach, the quality of the move evaluation procedure and the relevance of explicitly modeling transportation resources. New benchmark instances are also proposed.
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Kvaal, Erlend; Löw, Edgar, Novotny-Farkas, Zoltán, Panaretou, Argyro, Renders, Annelies & Sampers, Peter
(2023)
Classification and Measurement under IFRS 9: A Commentary and Suggestions for Future Research
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This paper discusses several issues that were raised by the International Accounting Standards Board (IASB) in their request for information for the post-implementation review (PIR) of the International Financial Reporting Standard (IFRS) 9: Financial instruments – Classification and Measurement. In doing so, we first review the related academic literature and present empirical evidence on the post-adoption impact of IFRS 9. We then discuss conceptual issues associated with the business model and cash flow characteristics assessment in IFRS 9, as well as issues associated with the presentation of fair value changes in other comprehensive income (OCI) and modifications to contractual cash flows. Finally, we identify gaps in the literature and provide suggestions for future research that can help inform accounting standard setters.
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Shukla, Anurag; Solbakken, Even André & Steen, Riana
(2023)
On the cyber-emergency preparedness in a resilient organization
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In recent years, the scientific fields of cyber-security and resilience engineering have emerged as new ways to deal with emerging risks in cyber-socio-technical systems. Unlike conventional security management approaches, focusing on historical data to provide an accurate risk picture, resilience engineering aims to enhance an organization's capacity to anticipate, monitor, and adapt to disruptions and surprises. However, with the increasing cyber threats and changes in national and international security policies, there is a pressing need to examine the resilience characteristics of cyber emergency preparedness in both public and private sectors. To address this need, this study adopts a triangulation method, through online survey and interview with two subject matter experts in the cyber-domain and explore factors that might contribute to enhancing cyber emergency preparedness in dealing with potential cyber threats and attacks. Findings suggest that front-line operators have limited information and capacity to process existing data in the domain of cyber security, highlighting a need for enhancing cyber-related knowledge across organizations. Furthermore, 25% of enterprises in the sample update their cybersecurity risk picture only once a year. The lack of more frequent updates downscales the contingency plans' thoroughness and puts companies in a vulnerable situation given the increasing trend of cyber-attacks.
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Hope, Ole-Kristian; Yue, Heng & Zhong, Qinlin
(2023)
Public Communication of Audit Risks and Related-Party Transactions: Evidence from China
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This paper examines whether and how firms’ engagement in related-party transactions (RPTs) is shaped by public communication of audit risks as required by the expanded audit report. Using the phased regulatory changes in China and a difference-in-differences design with firm fixed effects and matching, we find that firms significantly reduce their RPTs after the adoption of expanded audit reports (EARs). To investigate potential mechanisms, we find that (1) investor scrutiny increases after the adoption of EARs, (2) the reduction of RPTs is more pronounced when EARs are more likely to attract investor attention, and (3) the reduction of RPTs is weaker when firms are less concerned about investor scrutiny. The results suggest that EARs can attract investor scrutiny and increase the possible penalty associated with self-dealing, thus motivating firms to reduce RPTs.
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Berg, Terje & Lyngstadås, Hakim
(2023)
We’re only in it for the money? Developing sustainable literacy through management accounting curriculum
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This article addresses how and why introductory management accounting courses could contribute to sustainable literacy. Drawing on pragmatic constructivism we develop a course design. We base our discussions on teaching experience from two Business Schools. The proposed course design discusses sustainability around five common themes; (i) fundamental concepts, (ii) what are ‘net income’ and ‘value creation’, (iii) product costing and short-term decision-making, (iv) capital budgeting decisions, and (v) performance measurement. We demonstrate that it is possible to introduce sustainability and how it also allows for a better understanding of management accounting as such. Fundamentally, it is illustrated that critical thinking can be integrated at an introductory level in a management accounting course. As such, this study helps develop students’ sustainable literacy. By allowing sustainability to be a natural part of the standard subjects, the article claims that the subject area contributes to the future demands on management accountants as well.
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Hung, Chung-Yu & Shi, Zhenyang
(2023)
Peer-Specific Knowledge and Peer Group Properties in Relative Performance Evaluation
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Although relative performance evaluation (RPE) represents an important compensation practice, selecting a relevant peer firm poses a challenge for compensation committees. We study the implications of a committee’s peer-specific knowledge for the peer group property (i.e., RPE relevance). Committees likely know more about firms within their networks, and such peer-specific knowledge increases with their connections to potential peer firms. Our findings suggest that peer-specific knowledge facilitates not only the inclusion of more relevant peer firms, but also the exclusion of less relevant ones. Moreover, the committees incorporate connected peers’ performance information to a greater extent for risk removal. We address identification challenges by including an intensive set of fixed effects to control for characteristics of the focal and the peer firms and by exploiting exogenous changes to the connections between the committees and the peer firms. Our findings suggest that the compensation committee’s peer-specific knowledge facilitates the RPE practice.
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Mekonnen, Zeleke; Melaku, Tsegaye, Tucho, Gudina Terefe, Mecha, Mohammed, Årdal, Christine & Jahre, Marianne
(2023)
The knock-on effects of COVID-19 pandemic on the supply and availability of generic medicines in Ethiopia: mixed methods study
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COVID-19 pandemic posed a major impact on the availability and affordability of essential medicines. This study aimed to assess the knock-on effects of the COVID-19 pandemic on the supply availability of non-communicable chronic disease (NCD) medicines and paracetamol products in Ethiopia.
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Jahre, Marianne; Ditlev-Simonsen, Caroline Dale, Chao, Emmanuel, Czerwinska, Anna C & Mushi, Mary
(2023)
Sustainable New Business Development in the Global South - Supply Chains and Networks
The international journal of Business and Management in Emerging Markets (IJOBMEM), 2(1).
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Renders, Annelies; Fiechter, Peter & Novotny-Farkas, Zoltán
(2022)
Are Level 3 fair value remeasurements useful? Evidence from FAS 157 rollforward disclosures.
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Bø, Eirill; Hovi, Inger Beate & Pinchasik, Daniel Ruben
(2022)
COVID-19 disruptions and Norwegian food and pharmaceutical supply chains: Insights into supply chain risk management, resilience, and reliability
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The purpose of this study is to investigate how the COVID-19 crisis affected delivery security and firms’ preparedness and responses in Norway. Investigations focus on supply chains which were critical for maintaining the supply of essential goods when large parts of society closed down. This includes four firms belonging to food and pharmaceutical industries, representing different parts of the respective supply chains, and covering imports, exports, domestic distribution, and home-delivery services.
The originality of this article is that we employ theoretical models on supply chain risk management, resilience and reliability in conjunction, where these are usually used separately. Recognizing links, overlaps, and complementarity between the models, and using them step-by-step, we exploit synergies that enable more comprehensive assessments of strengths and weaknesses in firms’ supply chains, covering gaps, prioritizing between improvement areas, and collecting input towards detailed, actionable risk mitigation actions. Investigations build on semi-structured interviews, systematically covering the formative elements for each of the models. Using the models in conjunction, we compare the firms and identify differences, similarities, strengths, and weaknesses in the consequences of pandemic-related disruptions and how firms approached the challenges.
The main challenges for the firms were sudden demand changes early in the pandemic. While the firms had minor differences, their pre-pandemic contingency plans were generally not actionable or detailed enough, nor prepared for the pandemic's longevity. Therefore, more detailed and long-term guidelines are desirable, noting the importance and interrelationships of elements of supply chain risk management, resilience, and reliability. A common feature for all firms, and crucial for handling disruptions, is the importance of good and long-term relationships with upstream and downstream supply chain partners and the need for improving contingency plans and future resilience.
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Cahan, Steven F.; Che, Limei, Knechel, W. Robert & Svanstrøm, Tobias
(2022)
Do Audit Teams Affect Audit Production and Quality? Evidence from Audit Teams’ Industry Knowledge
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We examine how the extent and distribution of industry knowledge within an audit team affect audit outcomes. While prior research examining the role of auditors' industry knowledge focuses mainly on audit firms, audit offices, and audit partners, audits are conducted by audit teams. Using an audit framework and proprietary data from a Big 4 firm that includes audit hours for each team member, we find that Big 4 audit teams with higher average industry knowledge are associated with more audit effort. In contrast, we find mixed evidence on the relation between the average hourly internal cost rate and team knowledge. Furthermore, we find that balanced teams, which have at least one team member who qualifies as an industry specialist at both the senior rank and junior rank, produce higher-quality audits than teams that have no specialists. In contrast, the audit quality of unbalanced teams, which have a specialist at the senior rank but not the junior rank or vice versa, is not statistically different than teams with no specialists. Overall, our evidence suggests that both the extent and distribution of industry knowledge within a team matter for audit production and that industry knowledge is utilized more effectively when it is spread throughout the team. The findings have useful implications for audit firms and regulators regarding how team composition and industry knowledge affect audit outcomes.
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Ding, Junwen; Dauzère-Pérès, Stéphane, Shen, Liji & Lü, Zhipeng
(2022)
A Novel Evolutionary Algorithm for Energy-Efficient Scheduling in Flexible Job Shops
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Improving productivity at the expense of heavy energy consumption is often no longer possible in modern manufacturing industries. Through efficient scheduling technologies, however, we are able to still maintain high productivity while reducing energy costs. This paper addresses a flexible job shop scheduling problem under Time-Of-Use electricity tariffs with the objective of minimizing total energy consumption while considering a predefined makespan constraint. We propose a novel two-individual-based evolutionary (TIE) algorithm, which incorporates several distinguishing features such as a tabu search procedure, a topological order based recombination operator, a new neighborhood structure for this specific problem, and an approximate neighborhood evaluation method. Extensive experiments are conducted on widely used benchmark instances, which show that the proposed TIE outperforms traditional trajectory-based and population-based methods. We also analyze the key features of TIE to identify its critical success factors, and discuss the impact of varying key parameters of the problem to derive practical insights.
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Penz, Louise; Dauzère-Pérès, Stéphane & Nattaf, Margaux
(2022)
Minimizing the sum of completion times on a single machine with health index and flexible maintenance operations
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This paper is motivated by the development of Industry 4.0 and the need to better integrate production and maintenance decisions. Our problem considers a single machine on which jobs of different families are scheduled to minimize the sum of completion times. The machine has a health index which decreases when jobs are processed. To restore the machine health, maintenance operations must be scheduled. Moreover, to be scheduled, each job requires the machine to have a minimum health index which depends on the job family. Two cases are studied: (1) The daily case with a single flexible maintenance operation, and (2) The weekly case with two flexible maintenance operations. The second case is shown to be NP-complete. Two Mixed Integer Linear Programming models are presented for each case. The first model uses ‘‘classical’’ positional variables, while the second model improves the first model by using the notion of master sequence. Different valid inequalities are also proposed. Computational experiments show that the second model is much more efficient than the first model when solved with a standard solver, and the impact of the valid inequalities is
discussed.
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Gartner, Daniel; Viana, Joe, Tabar, Bahman Rostami , Pförringer, Dominik & Edenharter, Günther
(2022)
Challenging the throwaway culture in hospitals: Scheduling the mix of reusable and Single-Use bronchoscopes
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Optimal material resource planning is crucial to run safe and cost-efficient hospital services. In this article, we investigate a real problem in hospitals, motivated by an environmental and economically inefficient use of disposable, single-use, endoscopes. We develop a mathematical model and create a decision support tool to determine when reusable, multi-use, bronchoscopes should be sent for inspection including information to what extent single-use bronchoscopes can cover the remaining demand. The results show that the proposed approach can contain operational costs which consist of costs for buying single-use devices, inspection costs and reprocessing costs, i.e., sterilization of reusable devices. Our tool can assist hospitals to predict when reusable bronchoscopes should undergo inspection and whether the current inventory of reusable devices is sufficient to cover the demand. Finally, we evaluate the impact of variation in demand on total costs.
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Lyngstadås, Hakim & Berg, Terje
(2022)
Harder, better, faster, stronger: digitalisation and employee well-being in the operations workforce
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Operations management is experiencing a digital transformation that affects the entire industry landscape. There has been scant research on how digitalisation affects employee well-being in the operations workforce. Using self-determination theory, we bridge this research gap by examining how basic psychological needs among the operations workforce are affected by digitalisation. Our empirical data is collected by a survey from 132 employees in the operations job function in the U.S. The empirical evidence is analysed in a configurational manner by using a fuzzy set Qualitative Comparative Analysis. Our findings suggest there are five empirical important empirical solutions for explaining the presence of employee well-being, as well as four important empirical solutions for the absence (negation) of employee well-being. Our configurational solution consists mostly of both digital competence, social relatedness, and digital autonomy. This is in accordance with the self-determination theory. However, there are several alterations to how important they are among different configurational solutions. The presence of well-being in life and psychological well-being seems less relevant for obtaining well-being at work. We discuss the theoretical and practical implications of our findings and provide recommendations to managers for how to promote employee well-being.
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Engebrethsen, Erna S. & Dauzère-Pérès, Stéphane
(2022)
Transportation strategies for dynamic lot sizing: single or multiple modes?
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The complexity of decision-making for companies buying transportation services has increased due to the presence of more options and pricing schedules for transportation. Many companies make transportation and inventory decisions in an uncoordinated way and select only one transportation mode, missing opportunities for logistics cost savings. The experimental study in this paper is based on a real-world decision problem faced by a Scandinavian company that distributes fast-moving consumer goods and wants to determine its transportation strategy. We propose a novel multi-mode lot-sizing model with dynamic deterministic demand to illustrate the cost impact of accurately modelling piecewise-linear transportation costs and allowing a more flexible usage of transportation modes when planning order replenishments. We compare three transportation strategies with increasing degrees of flexibility: two single mode strategies, where one strategy is more flexible than the other, and a multi-mode strategy. We conclude that managers can significantly reduce costs by increasing the flexibility of mode selection in transportation strategies.
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Perraudat, Antoine; Dauzère-Pérès, Stéphane & Vialletelle, Philippe
(2022)
Optimizing multiple qualifications of products on non-identical parallel machines
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In some manufacturing contexts, such as semiconductor manufacturing, machines must be qualified, or eligible, to process a product, and machines cannot be qualified for all products. This paper investigates the problem of optimizing a given number of new qualifications of products to machines to maximize a flexibility measure that evaluates the balance of the qualification configuration of a work center in terms of utilization rate of machines on a set of non-identical parallel machines. Motivated by empirical observations, new solution approaches, notably inspired by heuristics for discrete location problems and based on the analysis of dual variables, are proposed and compared on industrial data from a semiconductor manufacturing facility and on randomly instances. The use of dual variables leads to heuristics that are effective both in terms of solution quality and computational time. The best proposed approach is currently used in the decision support system of a semiconductor manufacturing facility.
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Hope, Ole-Kristian; Rao, Pingui, Xu, Yanping & Yue, Heng
(2022)
Information sharing between mutual funds and auditors
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This paper examines whether there is information sharing between mutual funds and their auditors about the auditors’ other listed firm clients. Using data from the Chinese market, we find that mutual funds earn higher profits from trading in firms that share the same auditors. The effects are more pronounced when firms have a more opaque information environment and when the audit partners for the fund and the partners for the listed firm share school ties. The evidence is consistent with information flowing from auditors to mutual funds, providing mutual funds with an information advantage in firms that share the same auditors. Our findings are robust to the use of audit-firm mergers and acquisitions (M&As) as exogenous shocks and several other robustness checks. We further find that auditors benefit by charging higher audit fees for mutual fund clients and by improving their audit quality for listed firm clients. Our study provides evidence of bi-directional information sharing between two important market intermediaries.
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van Oorschot, Kim; Van Wassenhove, Luk N., Jahre, Marianne, Selviaridis, Kostas & de Vries, Harwin
(2022)
Drug shortages: A systems view of the current state
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The objective of this thought leadership article is to create a systems view of drug shortages based on the perceptions of practitioners and policymakers. We develop a comprehensive framework describing what stakeholders are currently doing when faced with drug shortages and show the outcomes of their actions. In a review of practitioner literature and public reports published from 2010 to 2020, we identify cause-and-effect relationships related to generic drug shortages in six high-income European countries (Belgium, France, the Netherlands, Norway, Sweden, and the UK) in normal times. By combining and connecting data from these different sources, we develop a systems view of the current state. Though several of the associations covered in the systems view are well known, putting them all together and considering their interrelationships is what is offered by this research. Based on this systems view, we derive three basic solution archetypes for drug shortages: (1) let the market handle it; (2) search for alternatives; and (3) bend the rules. The interactions between these archetypes generate causal ambiguity making it harder to understand and solve the problem as the side effects of solutions can be missed. We show how the interaction of archetypes can compromise intended behavior or escalate unintended behavior. However, our systems view allows us to suggest higher-level solution archetypes that overrule such side effects. The basic and higher-order solution archetypes can provide baselines for research and support the development of future interventions.
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Bygballe, Lena Elisabeth; Dubois, Anna & Jahre, Marianne
(2022)
The importance of resource interaction in strategies for managing supply chain disruptions
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The turbulent business environment highlights the need for strategies for mitigating, responding to, and recovering from (that is, managing) supply chain disruptions. Resources are central in these strategies but remain unspecified in the literature. This paper shows how the resource interaction approach (RIA) can help understanding resources in this setting by acknowledging their interactive and networked nature. Based on a conceptual discussion that compares key assumptions within the supply chain risk management (SCRM) and supply chain risk resilience (SCRes) literatures with the RIA, we propose an alternative approach to strategies for managing supply chain disruptions. We challenge the SCRM and SCRes literatures by emphasizing interdependence (as opposed to independence) and pointing to relationships as key resources in strategies for managing supply chain disruptions. Collaboration relying on an interplay between temporary and permanent organizing is suggested as a starting point instead of being just one of several alternative strategies.
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Bleibtreu, Christopher & Stefani, Ulrike
(2022)
The interdependence between market structure and the quality of audited reports: the case of non-audit services
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This paper addresses the effects of a prohibition of providing non-audit services
(NAS) to audit clients. By combining a strategic auditor–client game with a circular market-matching model that has an endogenous number of auditors, we take into account the interdependence between the auditors’ and clients’ incentives, the market structure, and the quality of audited reports. We show that the regulation’s effects depend on the preexisting audit market concentration and the types of blacklisted NAS. In sharp contrast to the effects that regulators desire, a prohibition of providing NAS to audit clients can further increase audit market concentration and decrease the quality of audited reports if the fees that auditors previously earned from providing the blacklisted NAS were relatively high, compared to the reduction in audit costs that result from spillovers. In contrast, a prohibition of the NAS that generate intense spillovers and low NAS fees can have the unexpected—but desired—effect of decreasing market concentration; however, reporting quality also decreases.
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Hope, Ole-Kristian; Li, Congcong, Ma, Mark Shuai & Su, Xijiang
(2022)
Is silence golden sometimes? Management guidance withdrawals during the COVID-19 pandemic
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The many management guidance withdrawals during the COVID-19 pandemic have attracted considerable attention from the media, investors, and regulators. This study analyzes the determinants and consequences of these withdrawals. We find that guidance withdrawals are due to economic uncertainty, resulting from firms’ exposure to the COVID-19 pandemic rather than poor financial performance. Also, the effect of COVID-19 exposure on guidance withdrawals is stronger when firms face higher litigation risk. Further, guidance withdrawals result in abnormally large trading volumes and high analyst forecast dispersion but do not harm stock prices or the level of analyst earnings forecasts. Overall we believe the findings have implications for understanding corporate disclosure practices during periods with heightened economic uncertainty.
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Christ, Quentin; Dauzère-Pérès, Stéphane & Lepelletier, Guillaume
(2022)
A three-step approach for decision support in operational production planning of complex manufacturing systems
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In this paper, a practical relevant operational production planning problem in complex manufacturing systems is addressed. In this problem, lots are planned individually to provide a more detailed plan than approaches that only consider production quantities. A three-step approach, which is currently fully integrated and used in a Decision Support System, is then introduced. This work follows the one of Mhiri et al. [2018. “Heuristic Algorithm for a WIP Projection Problem at Finite Capacity in Semiconductor Manufacturing.” IEEE Transactions on Semiconductor Manufacturing 31 (1): 62–75] who addressed this problem. We push the approach a step further by introducing new optimisation possibilities through new smoothing rules, whose performance is studied according to different indicators. Furthermore, we present the production planning process in which the decision support tool is embedded and how it bridges the gap between the upper and lower planning levels.
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Frennesson, Lina; Kembro, Joakim, de Vries, Harwin, Jahre, Marianne & Van Wassenhove, Luk
(2022)
“International humanitarian organizations’ perspectives on localization efforts”
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The humanitarian sector has formulated a collective strategic intent to localize. This involves delegating responsibilities and transferring capacities and resources to national and local actors. However, progress is slower than expected. Strategy execution is hard, and translating a general strategic intent to the actual way humanitarian organizations operate is not obvious. To suggest remedies for the slow progress, this paper investigates drivers and barriers for international humanitarian organizations (IHOs) to localize their logistics preparedness capacities. It is essential to understand IHOs' perspectives as they are global and powerful actors in the humanitarian sector and by far represent the largest recipients of donor funds. We focus on logistics since it constitutes key activities of strong local contextual character, such as procurement, warehousing, and transport. By interviewing practitioners from a representative set of large IHOs, and connecting the empirical insights with relevant theory, we unravel reasons that hinder localization. These include IHOs' strategic choices due to context-sensitive benefits of localization, mandated expectations on IHOs, the lack of internal drivers for IHOs to localize, and resistance to localize due to IHOs’ desire and motives for continued engagement in humanitarian aid. Based on these insights, actionable propositions are developed to help accelerate progress toward localization.
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Khadri, Ines Julia & Viana, Joe
(2022)
Simulation of IT Data Integration to Optimize an Antibiotics Supply Chain with System Dynamics
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Supply chain (SC) optimization is essential for a firm to cope with everchanging market conditions and disruptions. New technologies have allowed for more advanced supply chain optimization. This paper uses system dynamics (SD) simulation to model the effects of data integration technologies on an antibiotic (AB) SC operation. The study aims to improve the AB SC to benefit all relevant stakeholders including the patient population. We evaluate how IT integration technologies can improve communication across the SC to mitigate or reduce the impact of the of disruptions on AB users. The presented model is under development and is subject to structural and parametric changes as discussions continue with stakeholders about the system structure and what data can be used and disclosed. Despite extensive SC optimization literature there has been a growing call of an evidence base to support decision making relating to national medicine policies.
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Lang, Wei; Lang, Hao, Hui, Eddie C.M., Chen, Tingting, Wu, Jiemin & Jahre, Marianne
(2022)
Measuring urban vibrancy of neighborhood performance using social media data in Oslo, Norway
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The recent debate on urban vibrancy and its associated spatial characteristics worldwide has increasingly attracted the attention of planners and decision-makers in Norway and the European Union seeking to develop compact cities. This study investigated the spatial pattern of urban vibrancy associated with urban form and the determinants in Oslo, Norway. A total of 552 km2 of the Oslo central metropolitan area was classified into 12 neighborhood groups and a data-driven methodology was applied via SPSS, Python, and ArcGIS to analyze urban vibrancy, where each cell was denoted as a 1 km2 area of 24 variables. As a result of clustering via principal component analysis, six principal components were extracted with 12 critical factors. Results indicated that the location and distribution of commercial buildings, public buildings, residential buildings, and companies and the total population are the most important drivers of neighborhood vibrancy in Oslo. Vibrant neighborhoods usually appear in high-density, central urban areas with a high concentration of commercial and public buildings with various functions along main streets. In contrast, less vibrant neighborhoods have fewer service facilities and are surrounded by single residential areas, large venues, green spaces, vacant land, or land for transportation in the low-density suburban and semi-urbanized areas. This research offers a quantitative basis for a wider range of neighborhood performance assessments, provides a discussion of compact city theory, and draws the attention of decision-makers on planning policy at the neighborhood level, which can also be adapted to other European cities.