@inproceedings{WulfStrahringerWestner, author = {Wulf, Frederik and Strahringer, Susanne and Westner, Markus}, title = {Information security risks, benefits, and mitigation measures in cloud sourcing}, series = {Proceedings of the IEEE 21th Conference on Business Informatics (CBI): 2019, Moscow, Russia}, booktitle = {Proceedings of the IEEE 21th Conference on Business Informatics (CBI): 2019, Moscow, Russia}, pages = {258 -- 267}, abstract = {This paper develops a categorization of cloud security risks, elaborates how they impact information security, and discusses potential security benefits from cloud sourcing. This review integrates the literature on information systems and computer science to summarize managerial and technological mitigation measures that enhance cloud security. The analysis uncovers gaps regarding the empirical investigation of security considerations in the corporate decision-making process. Specifically, the micro level of how security comes into play in the decision-making process and whether mitigation measures proposed by scholars are practically feasible requires further investigation. Furthermore, the macro level, how stakeholders perceive cloud sourcing, is not yet well understood.}, subject = {Cloud Computing}, language = {en} } @inproceedings{KlotzWestnerStrahringeretal., author = {Klotz, Stefan and Westner, Markus and Strahringer, Susanne and Schieder, Christian}, title = {Transformed Knowledge Sharing Through Business-managed IT and Shadow IT}, series = {Proceedings of the 25th Americas Conference on Information Systems (AMCIS 2019), Canc{\´u}n, Mexiko, August 15-17}, booktitle = {Proceedings of the 25th Americas Conference on Information Systems (AMCIS 2019), Canc{\´u}n, Mexiko, August 15-17}, publisher = {AIS}, pages = {1 -- 10}, abstract = {Business-managed IT and Shadow IT describe the autonomous deployment/management of IT instances by business units. For the former, this happens in alignment with the IT organization of the enterprise, for the latter, without alignment. We analyze why and how Business-managed IT and Shadow IT transform knowledge sharing with two case studies drawing on the theoretical lens of the knowledge-based view. Several motivators lead to the autonomous implementation of knowledge management systems (KMSs), for example, shortcomings of existing systems. The implemented KMSs have multiple benefits for knowledge sharing, such as a reduction of knowledge sharing barriers. However, we notice that the Shadow IT KMS leads to challenges for cross-unit knowledge sharing due to the covert nature of Shadow IT. Based on the findings of our case studies, we develop a mid-range theory to explain the transformation of knowledge sharing in enterprises supported by Business-managed IT and Shadow IT.}, language = {en} } @inproceedings{KoenningHeinrichLeyhetal., author = {K{\"o}nning, Michael and Heinrich, Kai and Leyh, Christian and Westner, Markus}, title = {A quantitative analysis of culture-induced differences in pivotal IT outsourcing contract features}, series = {Proceedings of the 27th European Conference on Information Systems (ECIS 2019): Stockholm \& Uppsala, Sweden, June 8-14}, booktitle = {Proceedings of the 27th European Conference on Information Systems (ECIS 2019): Stockholm \& Uppsala, Sweden, June 8-14}, pages = {1 -- 15}, abstract = {More than 30 years after its first implementation, IT outsourcing (ITO) is unanimously considered a critical component of corporate strategy for private and public institutions alike. While implementations of ITO around the world share some common characteristics like typical reasons for outsourcing, key success factors, or dimensions along which they can be classified, extant research also points to regional differences. However, research on this topic, specifically regarding pivotal contract features like contract value, contract length, or pricing methods, is still in its infancy, and quantitative analyses on the subject are particularly scarce. We address this research gap by analyzing data on 14,917 ITO contracts closed between 2007 and 2017 through the lens of cultural regions and three statistical methods. The contribution of our paper is threefold. First, our descriptive analysis points to globally decreasing contract lengths and contract values, confirming previous studies and practice reports. Second, an ANOVA with independent post-hoc testing provides quantitative supportfor the degree of dissimilarity among individual regions in pivotal ITO contract features. Finally, our quantitative replication of a previous study identifies culture-induced regional differences between USA and Japan regarding the effect of influence factors on ITO contract features.}, subject = {Betriebliches Informationssytem}, language = {en} } @inproceedings{BockWeiss, author = {Bock, Sebastian and Weiß, Martin Georg}, title = {A Proof of Local Convergence for the Adam Optimizer}, series = {Proceedings of the 2019 International Joint Conference on Neural Networks (IJCNN), 2019, Budapest, Hungary, July 14-19}, volume = {2019}, booktitle = {Proceedings of the 2019 International Joint Conference on Neural Networks (IJCNN), 2019, Budapest, Hungary, July 14-19}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-501}, pages = {1 -- 8}, abstract = {Adaptive Moment Estimation (Adam) is a very popular training algorithm for deep neural networks, implemented in many machine learning frameworks. To the best of the authors knowledge no complete convergence analysis exists for Adam. The contribution of this paper is a method for the local convergence analysis in batch mode for a deterministic fixed training set, which gives necessary conditions for the hyperparameters of the Adam algorithm. Due to the local nature of the arguments the objective function can be non-convex but must be at least twice continuously differentiable.}, subject = {Neuronales Netz}, language = {en} } @inproceedings{BockWeiss, author = {Bock, Sebastian and Weiß, Martin Georg}, title = {Non-Convergence and Limit Cycles in the Adam Optimizer}, series = {Proceedings of the 28th International Conference on Artificial Neural Networks, 2019, Munich, Germany, September 17-19}, booktitle = {Proceedings of the 28th International Conference on Artificial Neural Networks, 2019, Munich, Germany, September 17-19}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-490}, pages = {232 -- 243}, abstract = {One of the most popular training algorithms for deep neural networks is the Adaptive Moment Estimation (Adam) introduced by Kingma and Ba. Despite its success in many applications there is no satisfactory convergence analysis: only local convergence can be shown for batch mode under some restrictions on the hyperparameters, counterexamples exist for incremental mode. Recent results show that for simple quadratic objective functions limit cycles of period 2 exist in batch mode, but only for atypical hyperparameters, and only for the algorithm without bias correction. We extend the convergence analysis to all choices of the hyperparameters for quadratic functions. This finally answers the question of convergence for Adam in batch mode to the negative. We analyze the stability of these limit cycles and relate our analysis to other results where approximate convergence was shown, but under the additional assumption of bounded gradients which does not apply to quadratic functions. The investigation heavily relies on the use of computer algebra due to the complexity of the equations.}, subject = {Neuronales Netz}, language = {en} } @article{KlotzKopperWestneretal., author = {Klotz, Stefan and Kopper, Andreas and Westner, Markus and Strahringer, Susanne}, title = {Causing factors, outcomes, and governance of Shadow IT and business-managed IT}, series = {International Journal of Information Systems and Project Management}, volume = {7}, journal = {International Journal of Information Systems and Project Management}, number = {1}, issn = {2182-7796}, doi = {10.12821/ijispm070102}, pages = {15 -- 43}, abstract = {Shadow IT and Business-managed IT describe the autonomous deployment/procurement or management of Information Technology (IT) instances, i.e., software, hardware, or IT services, by business entities. For Shadow IT, this happens covertly, i.e., without alignment with the IT organization; for Business-managed IT this happens overtly, i.e., in alignment with the IT organization or in a split responsibility model. We conduct a systematic literature review and structure the identified research themes in a framework of causing factors, outcomes, and governance. As causing factors, we identify enablers, motivators, and missing barriers. Outcomes can be benefits as well as risks/shortcomings of Shadow IT and Business-managed IT. Concerning governance, we distinguish two subcategories: general governance for Shadow IT and Business-managed IT and instance governance for overt Business-managed IT. Thus, a specific set of governance approaches exists for Business-managed IT that cannot be applied to Shadow IT due to its covert nature. Hence, we extend the existing conceptual understanding and allocate research themes to Shadow IT, Business-managed IT, or both concepts and particularly distinguish the governance of the two concepts. Besides, we find that governance themes have been the primary research focus since 2016, whereas older publications (until 2015) focused on causing factors.}, subject = {Betriebliches Informationssystem}, language = {en} } @article{StrasserWestnerStrahringer, author = {Strasser, Artur and Westner, Markus and Strahringer, Susanne}, title = {Knowledge transfer in IS offshoring}, series = {Journal of Systems and Information Technology}, volume = {21}, journal = {Journal of Systems and Information Technology}, number = {1}, issn = {1328-7265}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-294}, pages = {36 -- 62}, abstract = {Purpose This paper aims to investigate the main tasks, necessary skills, and the implementation of the offshore coordinator's role to facilitate knowledge transfer in information systems (IS) offshoring. Design/methodology/approach This empirical exploratory study uses the classical Delphi method that includes one qualitative and two quantitative rounds to collect data on IS experts' perceptions to seek a consensus among them. Findings The participants agreed, with strong consensus, for a set of 16 tasks and 15 skills. The tasks focused primarily on relationship management and facilitating knowledge transfer on different levels. The set of skills consists of approximately 25 per cent "hard" skills, e.g. professional language skills and project management skills, and approximately 75 per cent "soft" skills, e.g. interpersonal and communication skills and the ability to deal with conflict. Two factors mainly influence implementing the offshore coordinator role: project size and the number of projects to be supported simultaneously. Practical implications The findings provide indications of how to define and fulfill this crucial role in practice to facilitate the knowledge transfer process in a positive way. Originality/value Similarities in previous research findings are aggregated to examine the intermediate role in detail from a consolidated perspective. This results in the first comprehensive set of critical tasks and skills assigned to the competency dimensions of the universal competency framework, demonstrating which and how many competency dimensions are critical.}, subject = {Betriebliches Informationssystem}, language = {en} } @article{KoenningWestnerStrahringer, author = {K{\"o}nning, Michael and Westner, Markus and Strahringer, Susanne}, title = {A Systematic Review of Recent Developments in IT Outsourcing Research}, series = {Information Systems Management}, volume = {36}, journal = {Information Systems Management}, number = {1}, publisher = {Taylor \& Francis}, pages = {78 -- 96}, abstract = {Incomplete conceptualization of the information technology outsourcing (ITO) literature represents a challenge for navigating extant research and engaging into purposeful academic discourse. We extend the analysis of empirical findings on determinants of ITO decisions, outcomes, and governance. We identify increasing levels of research maturity, analyze effects of 38 new independent variables, highlight contradictory findings, and observe increasing interest in emerging topics such as innovation through ITO and multisourcing.}, subject = {Outsourcing}, language = {en} } @article{BaryWestnerStrahringer2019, author = {Bary, Benedikt von and Westner, Markus and Strahringer, Susanne}, title = {How decision maker's personal preferences influence the decision to backsource IT services}, series = {Journal of Information Technology Management (JITM)}, volume = {30}, journal = {Journal of Information Technology Management (JITM)}, number = {3}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-233}, pages = {1 -- 22}, year = {2019}, abstract = {To prepare their IT landscape for future business challenges, companies are changing their IT sourcing arrangements by using selective sourcing approaches as well as multi-sourcing with more but smaller sourcing contracts. Companies therefore have to reconsider and re-evaluate their IT sourcing setup more frequently. Collecting data from 251 global experts, we empirically tested the effect of service quality, relationship quality, and switching costs on IT sourcing decisions using partial least squares (PLS) analysis. Drawing on previously conducted expert interviews, our model extends previous studies and introduces a decision maker's sourcing preferences as a not yet examined moderator on IT sourcing decisions. This allows us to investigate the influence of the decision maker's beliefs on the decision process. We were able to confirm the negative effect of switching costs on a decision in favor of backsourcing, however we could not find significant support for the remaining hypotheses. We further discuss potential reasons for our findings and suggest future research opportunities based on our contribution.}, subject = {Outsourcing}, language = {en} } @article{EbigboMendelProbstetal., author = {Ebigbo, Alanna and Mendel, Robert and Probst, Andreas and Manzeneder, Johannes and Souza Jr., Luis Antonio de and Papa, Jo{\~a}o Paulo and Palm, Christoph and Messmann, Helmut}, title = {Computer-aided diagnosis using deep learning in the evaluation of early oesophageal adenocarcinoma}, series = {GuT}, volume = {68}, journal = {GuT}, number = {7}, publisher = {British Society of Gastroenterology}, doi = {10.1136/gutjnl-2018-317573}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-68}, pages = {1143 -- 1145}, abstract = {Computer-aided diagnosis using deep learning (CAD-DL) may be an instrument to improve endoscopic assessment of Barrett's oesophagus (BE) and early oesophageal adenocarcinoma (EAC). Based on still images from two databases, the diagnosis of EAC by CAD-DL reached sensitivities/specificities of 97\%/88\% (Augsburg data) and 92\%/100\% (Medical Image Computing and Computer-Assisted Intervention [MICCAI] data) for white light (WL) images and 94\%/80\% for narrow band images (NBI) (Augsburg data), respectively. Tumour margins delineated by experts into images were detected satisfactorily with a Dice coefficient (D) of 0.72. This could be a first step towards CAD-DL for BE assessment. If developed further, it could become a useful adjunctive tool for patient management.}, subject = {Speiser{\"o}hrenkrebs}, language = {en} }