TY - CHAP AU - Kuhlemann, Stefan AU - Sellmann, Meinolf AU - Tierney, Kevin ID - 14890 SN - 0302-9743 T2 - Lecture Notes in Computer Science TI - Exploiting Counterfactuals for Scalable Stochastic Optimization ER - TY - JOUR AU - Schryen, Guido AU - Kliewer, Natalia AU - Borndörfer, Ralf AU - Koch, Thorsten ID - 14540 JF - OR News TI - High-Performance Business Computing – Parallel Algorithms and Implementations for Solving Problems in Operations Research and Data Analysis VL - 65 ER - TY - CONF AB - When responding to natural disasters, professional relief units are often supported by many volunteers which are not affiliated to humanitarian organizations. The effective coordination of these volunteers is crucial to leverage their capabilities and to avoid conflicts with professional relief units. In this paper, we empirically identify key requirements that professional relief units pose on this coordination. Based on these requirements, we suggest a decision model. We computationally solve a real-world instance of the model and empirically validate the computed solution in interviews with practitioners. Our results show that the suggested model allows for solving volunteer coordination tasks of realistic size near-optimally within short time, with the determined solution being well accepted by practitioners. We also describe in this article how the suggested decision support model is integrated in the volunteer coordination system which we develop in joint cooperation with a disaster management authority and a software development company. AU - Rauchecker, Gerhard AU - Schryen, Guido ID - 5675 KW - Coordination of spontaneous volunteers KW - volunteer coordination system KW - decision support KW - scheduling optimization model KW - linear programming T2 - Proceedings of the 15th International Conference on Information Systems for Crisis Response and Management TI - Decision Support for the Optimal Coordination of Spontaneous Volunteers in Disaster Relief ER - TY - CONF AU - Prester, Julian AU - Wagner, Gerit AU - Schryen, Guido ID - 5681 T2 - Proceedings of the 2018 International Conference on Information Systems (ICIS 2018) TI - Classifying the Ideational Impact of IS Review Articles: A Natural Language Processing Based Approach ER - TY - BOOK AU - Schillinger, Rolf AU - Schryen, Guido ID - 6164 SN - 978-3-88246-374-3 TI - Security in Highly Connected IT Systems – Results of the Bavarian Research Alliance FORSEC ER - TY - JOUR AB - The need to protect resources against attackers is reflected by huge information security investments of firms worldwide. In the presence of budget constraints and a diverse set of assets to protect, organizations have to decide in which IT security measures to invest, how to evaluate those investment decisions, and how to learn from past decisions to optimize future security investment actions. While the academic literature has provided valuable insights into these issues, there is a lack of empirical contributions. To address this lack, we conduct a theory-based exploratory multiple case study. Our case study reveals that (1) firms? investments in information security are largely driven by external environmental and industry-related factors, (2) firms do not implement standardized decision processes, (3) the security process is perceived to impact the business process in a disturbing way, (4) both the implementation of evaluation processes and the application of metrics are hardly existent and (5) learning activities mainly occur at an ad-hoc basis. AU - Weishäupl, Eva AU - Yasasin, Emrah AU - Schryen, Guido ID - 5586 JF - Computers & Security KW - Information Security Investments KW - Multiple Case Study KW - Organizations KW - Single Loop Learning KW - Double Loop Learning TI - Information Security Investments: An Exploratory Multiple Case Study on Decision-Making, Evaluation and Learning VL - 77 ER - TY - CONF AU - Schuster, Richard AU - Wagner, Gerit AU - Schryen, Guido ID - 5600 T2 - Proceedings of the 2018 International Conference on Information Systems (ICIS 2018) TI - Information Systems Design Science Research and Cumulative Knowledge Development: An Exploratory Study ER - TY - CHAP AU - Hallmann, Corinna AU - Burmeister, Sascha Christian AU - Wissing, Michaela AU - Suhl, Leena ID - 14856 SN - 1865-0929 T2 - Communications in Computer and Information Science TI - Heuristics and Simulation for Water Tank Optimization ER - TY - CHAP AU - Hallmann, Corinna AU - Kuhlemann, Stefan ID - 14861 SN - 0721-5924 T2 - Operations Research Proceedings TI - Model Generator for Water Distribution Systems ER - TY - CONF AB - We consider Max-min Share (MmS) fair allocations of indivisible chores (items with negative utilities). We show that allocation of chores and classical allocation of goods (items with positive utilities) have some fundamental connections but also differences which prevent a straightforward application of algorithms for goods in the chores setting and viceversa. We prove that an MmS allocation does not need to exist for chores and computing an MmS allocation - if it exists - is strongly NP-hard. In view of these non-existence and complexity results, we present a polynomial-time 2-approximation algorithm for MmS fairness for chores. We then introduce a new fairness concept called optimal MmS that represents the best possible allocation in terms of MmS that is guaranteed to exist. We use connections to parallel machine scheduling to give (1) a polynomial-time approximation scheme for computing an optimal MmS allocation when the number of agents is fixed and (2) an effective and efficient heuristic with an ex-post worst-case analysis. AU - Aziz, Haris AU - Rauchecker, Gerhard AU - Schryen, Guido AU - Walsh, Toby ID - 5692 IS - 1 T2 - Thirty-First AAAI Conference on Artificial Intelligence (AAAI-17) TI - Algorithms for Max-Min Share Fair Allocation of Indivisible Chores VL - 31 ER - TY - CONF AB - Design science is a fundamental research stream that contends its position in the information systems discipline. While ongoing debates address the relative importance of design science contributions in the information systems community, insights into the scientific impact of design science research (DSR) are missing and this lack of understanding arguably poses challenges to an informed discourse. To identify the most influential papers and those factors that explain their scientific impact, this paper presents an exploratory study of the scientific impact of DSR papers published in the AIS Senior Scholars' Basket of Journals. We uncover the current DSR landscape by taking stock of influential papers and theories and develop a model to explain the scientific impact of DSR papers. Our findings show that scientific impact is significantly explained by theorization and novelty. We discuss how the implications of our work can be projected on the overarching discourse on DSR. AU - Wagner, Gerit AU - Prester, Julian AU - Schryen, Guido ID - 5594 T2 - 38th International Conference on Information Systems TI - Exploring the Scientific Impact of Information Systems Design Science Research: A Scientometric Study ER - TY - JOUR AU - Schryen, Guido AU - Hristova, Diana ID - 5626 JF - Smart Data Radar (Deutsche Bank) TI - High-Performance Business Computing - Effizienzsteigerung durch Parallelisierung ER - TY - JOUR AB - Literature reviews (LRs) are recognized for their increasing impact in the information systems literature. Methodologists have drawn attention to the question of how we can leverage the value of LRs to preserve and generate knowledge. The panelists who participated in the discussion of ?Standalone Literature Reviews in IS Research: What Can Be Learnt from the Past and Other Fields?? at ICIS 2016 in Dublin acknowledged this significant issue and debated a) what the IS field can learn from other fields and where IS-specific challenges occur, b) how the IS field should move forward to foster the genre of LRs, and c) what best practices are to train doctoral IS students in publishing LRs. This article reports the key takeaways of this panel discussion. Guidance for IS scholars is provided on how to conduct LRs that contribute to the cumulative knowledge development within and across the IS field to best prepare the next generation of IS scholars. AU - Schryen, Guido AU - Benlian, Alexander AU - Rowe, Frantz AU - Shirley, Gregor AU - Larsen, Kai AU - Petter, Stacie AU - Par{\'e}, Guy AU - Wagner, Gerit AU - Haag, Steffi AU - Yasasin, Emrah ID - 5633 JF - Communications of the AIS KW - Literature Review KW - Review Methodology KW - Research Methodology KW - Doctoral Training SN - 1529-3181 TI - Literature Reviews in IS Research: What Can Be Learnt from the Past and Other Fields? VL - 40 ER - TY - JOUR AB - Multi-attribute value theory (MAVT)-based recommender systems have been proposed for dealing with issues of existing recommender systems, such as the cold-start problem and changing preferences. However, as we argue in this paper, existing MAVT-based methods for measuring attribute importance weights do not fit the shopping tasks for which recommender systems are typically used. These methods assume well-trained decision makers who are willing to invest time and cognitive effort, and who are familiar with the attributes describing the available alternatives and the ranges of these attribute levels. Yet, recommender systems are most often used by consumers who are usually not familiar with the available attributes and ranges and who wish to save time and effort. Against this background, we develop a new method, based on a product configuration process, which is tailored to the characteristics of these particular decision makers. We empirically compare our method to SWING, ranking-based conjoint analysis and TRADEOFF in a between-subjects laboratory experiment with 153 participants. Results indicate that our proposed method performs better than TRADEOFF and CONJOINT and at least as well as SWING in terms of recommendation accuracy, better than SWING and TRADEOFF and at least as well as CONJOINT in terms of cognitive load, and that participants were faster with our method than with any other method. We conclude that our method is a promising option to help support consumers' decision processes in e-commerce shopping tasks. AU - Scholz, Michael AU - Dorner, Verena AU - Schryen, Guido AU - Benlian, Alexander ID - 5671 IS - 1 JF - European Journal of Operational Research KW - E-Commerce KW - Recommender System KW - Attribute Weights KW - Configuration System KW - Decision Support TI - A configuration-based recommender system for supporting e-commerce decisions VL - 259 ER - TY - CHAP AU - Beckschäfer, Michaela AU - Malberg, Simon AU - Tierney, Kevin AU - Weskamp, Christoph ID - 14857 SN - 0302-9743 T2 - Lecture Notes in Computer Science TI - Simulating Storage Policies for an Automated Grid-Based Warehouse System ER - TY - JOUR AU - Rauchecker, Gerhard AU - Schryen, Guido ID - 5676 JF - Im Einsatz TI - Projekt KUBAS: Koordination ungebundener Vor-Ort-Helfer VL - 23 ER - TY - CONF AU - Wagner, Gerit AU - Prester, Julian AU - Roche, Maria AU - Benlian, Alexander AU - Schryen, Guido ID - 5595 T2 - International Conference on Information Systems TI - Factors Affecting the Scientific Impact of Literature Reviews: A Scientometric Study ER - TY - JOUR AB - CAPTCHAs are challenge-response tests that aim at preventing unwanted machines, including bots, from accessing web services while providing easy access for humans. Recent advances in artificial-intelligence based attacks show that the level of security provided by many state-of-the-art text-based CAPTCHAs is declining. At the same time, techniques for distorting and obscuring the text, which are used to maintain the level of security, make text-based CAPTCHAs diffcult to solve for humans, and thereby further degrade usability. The need for developing alternative types of CAPTCHAs which improve both, the current security and usability levels, has been emphasized by several researchers. With this study, we contribute to research through (1) the development of two new face recognition CAPTCHAs (Farett-Gender and Farett-Gender&Age), (2) the security analysis of both procedures, and (3) the provision of empirical evidence that one of the suggested CAPTCHAs (Farett-Gender) is similar to Google's reCAPTCHA and better than KCAPTCHA concerning effectiveness (error rates), superior to both regarding learnability and satisfaction but not effciency. AU - Schryen, Guido AU - Wagner, Gerit AU - Schlegel, Alexander ID - 5617 IS - July JF - Computers & Security KW - CAPTCHA KW - Usability KW - Facial features KW - Gender classiffcation KW - Age classification KW - Face recognition reverse Turing test TI - Development of two novel face-recognition CAPTCHAs: a security and usability study VL - 60 ER - TY - CONF AB - Many academic disciplines - including information systems, computer science, and operations management - face scheduling problems as important decision making tasks. Since many scheduling problems are NP-hard in the strong sense, there is a need for developing solution heuristics. For scheduling problems with setup times on unrelated parallel machines, there is limited research on solution methods and to the best of our knowledge, parallel computer architectures have not yet been taken advantage of. We address this gap by proposing and implementing a new solution heuristic and by testing different parallelization strategies. In our computational experiments, we show that our heuristic calculates near-optimal solutions even for large instances and that computing time can be reduced substantially by our parallelization approach. AU - Rauchecker, Gerhard AU - Schryen, Guido ID - 5678 KW - scheduling KW - decision support KW - heuristic KW - high performance computing KW - parallel algorithms T2 - Australasian Conference on Information Systems TI - High-Performance Computing for Scheduling Decision Support: A Parallel Depth-First Search Heuristic ER - TY - JOUR AB - Cloud computing promises the flexible delivery of computing services in a pay-as-you-go manner. It allows customers to easily scale their infrastructure and save on the overall cost of operation. However Cloud service offerings can only thrive if customers are satisfied with service performance. Allow-ing instantaneous access and flexible scaling while maintaining the service levels and offering competitive prices poses a significant challenge to Cloud Computing providers. Furthermore services will remain available in the long run only if this business generates a stable revenue stream. To address these challenges we introduce novel policy-based service admission control mod-els that aim at maximizing the revenue of Cloud providers while taking in-formational uncertainty regarding resource requirements into account. Our evaluation shows that policy-based approaches statistically significantly out-perform first come first serve approaches, which are still state of the art. Furthermore the results give insights in how and to what extent uncertainty has a negative impact on revenue. AU - Püschel, Tim AU - Schryen, Guido AU - Hristova, Diana AU - Neumann, Dirk ID - 5679 IS - 2 JF - European Journal of Operational Research KW - admission control KW - informational uncertainty KW - revenue management KW - cloud computing TI - Revenue Management for Cloud Computing Providers: Decision Models for Service Admission Control under Non-probabilistic Uncertainty VL - 244 ER -