@inproceedings{54539, author = {{Bauer, Maike}}, location = {{Essen (online)}}, title = {{{Diaspora-Literatures in the EFL Classroom – A new Didactic Impulse?}}}, year = {{2021}}, } @article{49463, author = {{Trang, Simon Thanh-Nam and Nastjuk, I.}}, journal = {{Computers & Security}}, title = {{{Examining the role of stress and information security policy design in information security compliance behaviour: An experimental study of in-task behaviour}}}, volume = {{104}}, year = {{2021}}, } @article{49464, author = {{Trang, Simon Thanh-Nam and Weiger, W.}}, journal = {{Computers in Human Behavior}}, title = {{{The perils of gamification: Does engaging with gamified services increase users’ willingness to disclose personal information?}}}, volume = {{116}}, year = {{2021}}, } @article{49462, author = {{Brendel, A.B. and Greve, M. and Masuch, K. and Trang, Simon Thanh-Nam}}, journal = {{HMD Praxis der Wirtschaftsinformatik}}, pages = {{698–711}}, title = {{{Corona Tracing Apps – Eine Analyse und Strukturierung des europäischen Marktes}}}, volume = {{58}}, year = {{2021}}, } @inbook{54586, author = {{Manzoor, Ali and Saleem, Muhammad and Ngonga Ngomo, Axel-Cyrille}}, booktitle = {{The Semantic Web: ESWC 2021 Satellite Events}}, isbn = {{9783030804176}}, issn = {{0302-9743}}, publisher = {{Springer International Publishing}}, title = {{{Unsupervised Relation Extraction Using Sentence Encoding}}}, doi = {{10.1007/978-3-030-80418-3_25}}, year = {{2021}}, } @inproceedings{45840, abstract = {{Argumentation is a widely applied framework for modeling and evaluating arguments and its reasoning with various applications. Popular frameworks are abstract argumentation (Dung’s framework) or logic-based argumentation (Besnard-Hunter’s framework). Their computational complexity has been studied quite in-depth. Incorporating treewidth into the complexity analysis is particularly interesting, as solvers oftentimes employ SAT-based solvers, which can solve instances of low treewidth fast. In this paper, we address whether one can design reductions from argumentation problems to SAT-problems while linearly preserving the treewidth, which results in decomposition-guided (DG) reductions. It turns out that the linear treewidth overhead caused by our DG reductions, cannot be significantly improved under reasonable assumptions. Finally, we consider logic-based argumentation and establish new upper bounds using DG reductions and lower bounds.}}, author = {{Fichte, Johannes and Hecher, Markus and Mahmood, Yasir and Meier, Arne}}, booktitle = {{Proceedings of the Thirtieth International Joint Conference on Artificial Intelligence}}, publisher = {{International Joint Conferences on Artificial Intelligence Organization}}, title = {{{Decomposition-Guided Reductions for Argumentation and Treewidth}}}, doi = {{10.24963/ijcai.2021/259}}, year = {{2021}}, } @article{45844, abstract = {{Abstract Abductive reasoning is a non-monotonic formalism stemming from the work of Peirce. It describes the process of deriving the most plausible explanations of known facts. Considering the positive version, asking for sets of variables as explanations, we study, besides the problem of wether there exists a set of explanations, two explanation size limited variants of this reasoning problem (less than or equal to, and equal to a given size bound). In this paper, we present a thorough two-dimensional classification of these problems: the first dimension is regarding the parameterized complexity under a wealth of different parameterizations, and the second dimension spans through all possible Boolean fragments of these problems in Schaefer’s constraint satisfaction framework with co-clones (T. J. Schaefer. The complexity of satisfiability problems. In Proceedings of the 10th Annual ACM Symposium on Theory of Computing, May 1–3, 1978, San Diego, California, USA, R.J. Lipton, W.A. Burkhard, W.J. Savitch, E.P. Friedman, A.V. Aho eds, pp. 216–226. ACM, 1978). Thereby, we almost complete the parameterized complexity classification program initiated by Fellows et al. (The parameterized complexity of abduction. In Proceedings of the Twenty-Sixth AAAI Conference on Articial Intelligence, July 22–26, 2012, Toronto, Ontario, Canada, J. Homann, B. Selman eds. AAAI Press, 2012), partially building on the results by Nordh and Zanuttini (What makes propositional abduction tractable. Artificial Intelligence, 172, 1245–1284, 2008). In this process, we outline a fine-grained analysis of the inherent parameterized intractability of these problems and pinpoint their FPT parts. As the standard algebraic approach is not applicable to our problems, we develop an alternative method that makes the algebraic tools partially available again.}}, author = {{Mahmood, Yasir and Meier, Arne and Schmidt, Johannes}}, issn = {{0955-792X}}, journal = {{Journal of Logic and Computation}}, keywords = {{Logic, Hardware and Architecture, Arts and Humanities (miscellaneous), Software, Theoretical Computer Science}}, number = {{1}}, pages = {{266--296}}, publisher = {{Oxford University Press (OUP)}}, title = {{{Parameterized complexity of abduction in Schaefer’s framework}}}, doi = {{10.1093/logcom/exaa079}}, volume = {{31}}, year = {{2021}}, } @inproceedings{45841, abstract = {{Logic-based argumentation is a well-established formalism modeling nonmonotonic reasoning. It has been playing a major role in AI for decades, now. Informally, a set of formulas is the support for a given claim if it is consistent, subset-minimal, and implies the claim. In such a case, the pair of the support and the claim together is called an argument. In this paper, we study the propositional variants of the following three computational tasks studied in argumentation: ARG (exists a support for a given claim with respect to a given set of formulas), ARG-Check (is a given set a support for a given claim), and ARG-Rel (similarly as ARG plus requiring an additionally given formula to be contained in the support). ARG-Check is complete for the complexity class DP, and the other two problems are known to be complete for the second level of the polynomial hierarchy and, accordingly, are highly intractable. Analyzing the reason for this intractability, we perform a two-dimensional classification: first, we consider all possible propositional fragments of the problem within Schaefer's framework, and then study different parameterizations for each of the fragment. We identify a list of reasonable structural parameters (size of the claim, support, knowledge-base) that are connected to the aforementioned decision problems. Eventually, we thoroughly draw a fine border of parameterized intractability for each of the problems showing where the problems are fixed-parameter tractable and when this exactly stops. Surprisingly, several cases are of very high intractability (paraNP and beyond).}}, author = {{Mahmood, Yasir and Meier, Arne and Schmidt, Johannes}}, booktitle = {{Proceedings of the AAAI Conference on Artificial Intelligence}}, issn = {{2374-3468}}, keywords = {{General Medicine}}, number = {{7}}, pages = {{6426--6434}}, publisher = {{Association for the Advancement of Artificial Intelligence (AAAI)}}, title = {{{Parameterized Complexity of Logic-Based Argumentation in Schaefer's Framework}}}, doi = {{10.1609/aaai.v35i7.16797}}, volume = {{35}}, year = {{2021}}, } @inproceedings{47265, author = {{Huaman, Nicolas and von Skarczinski, Bennet and Stransky, Christian and Wermke, Dominik and Acar, Yasemin and Dreißigacker, Arne and Fahl, Sascha}}, booktitle = {{30th USENIX Security Symposium, USENIX Security 2021, August 11-13, 2021}}, editor = {{Bailey, Michael and Greenstadt, Rachel}}, pages = {{1235–1252}}, publisher = {{USENIX Association}}, title = {{{A Large-Scale Interview Study on Information Security in and Attacks against Small and Medium-sized Enterprises}}}, year = {{2021}}, } @inproceedings{47268, author = {{Stransky, Christian and Wermke, Dominik and Schrader, Johanna and Huaman, Nicolas and Acar, Yasemin and Fehlhaber, Anna Lena and Wei, Miranda and Ur, Blase and Fahl, Sascha}}, booktitle = {{Seventeenth Symposium on Usable Privacy and Security, SOUPS 2021, August 8-10, 2021}}, editor = {{Chiasson, Sonia}}, pages = {{437–454}}, publisher = {{USENIX Association}}, title = {{{On the Limited Impact of Visualizing Encryption: Perceptions of E2E Messaging Security}}}, year = {{2021}}, } @inproceedings{47267, author = {{Huaman, Nicolas and Amft, Sabrina and Oltrogge, Marten and Acar, Yasemin and Fahl, Sascha}}, booktitle = {{2021 IEEE Symposium on Security and Privacy (SP)}}, publisher = {{IEEE}}, title = {{{They Would do Better if They Worked Together: The Case of Interaction Problems Between Password Managers and Websites}}}, doi = {{10.1109/sp40001.2021.00094}}, year = {{2021}}, } @inproceedings{47266, author = {{Haney, Julie M. and Acar, Yasemin and Furman, Susanne}}, booktitle = {{30th USENIX Security Symposium, USENIX Security 2021, August 11-13, 2021}}, editor = {{Bailey, Michael and Greenstadt, Rachel}}, pages = {{411–428}}, publisher = {{USENIX Association}}, title = {{{"It’s the Company, the Government, You and I": User Perceptions of Responsibility for Smart Home Privacy and Security}}}, year = {{2021}}, } @inproceedings{47264, author = {{Oltrogge, Marten and Huaman, Nicolas and Amft, Sabrina and Acar, Yasemin and Backes, Michael and Fahl, Sascha}}, booktitle = {{30th USENIX Security Symposium, USENIX Security 2021, August 11-13, 2021}}, editor = {{Bailey, Michael and Greenstadt, Rachel}}, pages = {{4347–4364}}, publisher = {{USENIX Association}}, title = {{{Why Eve and Mallory Still Love Android: Revisiting TLS (In)Security in Android Applications}}}, year = {{2021}}, } @inproceedings{47269, author = {{Neil, Lorenzo and Bouma-Sims, Elijah and Lafontaine, Evan and Acar, Yasemin and Reaves, Bradley}}, booktitle = {{Seventeenth Symposium on Usable Privacy and Security, SOUPS 2021, August 8-10, 2021}}, editor = {{Chiasson, Sonia}}, pages = {{359–376}}, publisher = {{USENIX Association}}, title = {{{Investigating Web Service Account Remediation Advice}}}, year = {{2021}}, } @phdthesis{47271, author = {{Acar, Yasemin}}, publisher = {{University of Marburg, Germany}}, title = {{{Human Factors in Secure Software Development}}}, year = {{2021}}, } @inproceedings{46315, abstract = {{We propose a novel method for automated algorithm selection in the domain of single-objective continuous black-box optimization. In contrast to existing methods, we use convolutional neural networks as the selection apparatus which bases its decision on a so-called ‘fitness map’. This fitness map is a 2D representation of a two dimensional search space where different gray scales indicate the quality of found solutions in certain areas. Our devised approach uses a modular CMA-ES framework which offers the option to create the conventional CMA-ES, CMA-ES with the alternate step-size adaptation and many other variants proposed over the years. In total, 4 608 different configurations are possible where most configurations are of complementary nature. In this proof-of-concept work, we consider a subset of 32 possible configurations. The developed method is evaluated against an excerpt of BBOB functions and its performance is compared against baselines that are commonly used in automated algorithm selection - the best standalone algorithm (configuration) and the best obtainable sequence of configurations. While the results indicate that the use of the fitness map is not superior on every benchmark problem, it indubitably shows its merit on more hard-to-solve problems. This offers a promising perspective for generalizing to other types of optimization problems and problem domains.}}, author = {{Prager, Raphael Patrick and Seiler, Moritz and Trautmann, Heike and Kerschke, Pascal}}, booktitle = {{2021 IEEE Symposium Series on Computational Intelligence (SSCI)}}, pages = {{1--8}}, title = {{{Towards Feature-Free Automated Algorithm Selection for Single-Objective Continuous Black-Box Optimization}}}, doi = {{10.1109/SSCI50451.2021.9660174}}, year = {{2021}}, } @inproceedings{46312, abstract = {{Abuse and hate are penetrating social media and many comment sections of news media companies. These platform providers invest considerable efforts to mod- erate user-generated contributions to prevent losing readers who get appalled by inappropriate texts. This is further enforced by legislative actions, which make non-clearance of these comments a punishable action. While (semi-)automated solutions using Natural Language Processing and advanced Machine Learning techniques are getting increasingly sophisticated, the domain of abusive language detection still struggles as large non-English and well-curated datasets are scarce or not publicly available. With this work, we publish and analyse the largest annotated German abusive language comment datasets to date. In contrast to existing datasets, we achieve a high labelling standard by conducting a thorough crowd-based an- notation study that complements professional moderators’ decisions, which are also included in the dataset. We compare and cross-evaluate the performance of baseline algorithms and state-of-the-art transformer-based language models, which are fine-tuned on our datasets and an existing alternative, showing the usefulness for the community.}}, author = {{Assenmacher, Dennis and Niemann, Marco and Müller, Kilian and Seiler, Moritz and Riehle, Dennis M. and Trautmann, Heike}}, booktitle = {{Proceedings of the Neural Information Processing Systems Track on Datasets and Benchmarks 1 (NeurIPS Datasets and Benchmarks 2021)}}, pages = {{1–14}}, title = {{{RP-Mod & RP-Crowd: Moderator- and Crowd-Annotated German News Comment Datasets}}}, year = {{2021}}, } @book{54654, editor = {{Bergmann, Claudia D. and Kranemann, Benedikt}}, publisher = {{Aschendorff Verlag}}, title = {{{Analogie und Differenz: Das dynamische Verhältnis von jüdischer und christlicher Liturgie // Analogy and Difference: The Ever-Changing Relationship of Jewish and Christian Liturgy}}}, year = {{2021}}, } @inproceedings{46313, abstract = {{Classic automated algorithm selection (AS) for (combinatorial) optimization problems heavily relies on so-called instance features, i.e., numerical characteristics of the problem at hand ideally extracted with computationally low-demanding routines. For the traveling salesperson problem (TSP) a plethora of features have been suggested. Most of these features are, if at all, only normalized imprecisely raising the issue of feature values being strongly affected by the instance size. Such artifacts may have detrimental effects on algorithm selection models. We propose a normalization for two feature groups which stood out in multiple AS studies on the TSP: (a) features based on a minimum spanning tree (MST) and (b) a k-nearest neighbor graph (NNG) transformation of the input instance. To this end we theoretically derive minimum and maximum values for properties of MSTs and k-NNGs of Euclidean graphs. We analyze the differences in feature space between normalized versions of these features and their unnormalized counterparts. Our empirical investigations on various TSP benchmark sets point out that the feature scaling succeeds in eliminating the effect of the instance size. Eventually, a proof-of-concept AS-study shows promising results: models trained with normalized features tend to outperform those trained with the respective vanilla features.}}, author = {{Heins, Jonathan and Bossek, Jakob and Pohl, Janina and Seiler, Moritz and Trautmann, Heike and Kerschke, Pascal}}, booktitle = {{Proceedings of the 16$^th$ ACM/SIGEVO Conference on Foundations of genetic Algorithms (FOGA XVI)}}, editor = {{Computing Machinery Association, for}}, pages = {{1–15}}, publisher = {{Association for Computing Machinery}}, title = {{{On the Potential of Normalized TSP Features for Automated Algorithm Selection}}}, doi = {{10.1145/3450218.3477308}}, year = {{2021}}, } @article{33668, abstract = {{AbstractVaccinations, lockdowns and testing strategies are three potential elements of an effective anti-coronavirus, and in particular Covid-19, health policy. The following analysis considers - within a simple model - the potentially crucial role of a Corona testing approach in combination with a quarantine approach which is shown herein to be a substitute for broad lockdown measures. The cost of lockdowns/shutdowns are rather high so that – beyond progress in terms of a broad vaccination program – a rational testing strategy should also be carefully considered. Testing has to be organized on the basis of an adequate testing infrastructure which could largely be implemented in firms, schools, universities and public administration settings. As regards the cost of a systematic broad Covid-19 testing strategy, these could come close to 0.5% of national income if there are no vaccinations. The Testing & Quarantine approach suggested here – with tests for symptomatic as well as asymptomatic people - is based on a random sampling and would require rather broad and frequent testing; possibly one test per person every 7–10 days. At the same time, one should consider that the cost of further lockdowns/shutdowns of a duration of 1 month could be very high, such that a standard cost benefit analysis supports the testing approach suggested herein. Also, an optimal policy mix could be designed where both vaccinations and testing play a crucial role. As of late January 2021, no further lockdowns in Germany and other OECD countries would be necessary if a broad testing infrastructure can be established rather quickly. This in turn will reinforce economic optimism and help to jumpstart economic growth in Europe, the US and Asia in a solid way. The basic logic of the testing approach pointed out here for industrialized countries could also be applied in developing countries. The approach presented is complementary to the IMF analysis of Cherif/Hasanov.}}, author = {{Gries, Thomas and Welfens, Paul J. J.}}, issn = {{1612-4804}}, journal = {{International Economics and Economic Policy}}, keywords = {{Economics and Econometrics}}, number = {{1}}, pages = {{1--24}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Testing as an approach to control the Corona epidemic dynamics and avoid lockdowns}}}, doi = {{10.1007/s10368-021-00495-5}}, volume = {{18}}, year = {{2021}}, }