IT University of Copenhagen

About: IT University of Copenhagen is a education organization based out in Copenhagen, Hovedstaden, Denmark. It is known for research contribution in the topics: Context (language use) & Game design. The organization has 888 authors who have published 2910 publications receiving 73775 citations. The organization is also known as: IT-Universitetet i København.

From game design elements to gamefulness: defining "gamification"

Abstract: Recent years have seen a rapid proliferation of mass-market consumer software that takes inspiration from video games. Usually summarized as "gamification", this trend connects to a sizeable body of existing concepts and research in human-computer interaction and game studies, such as serious games, pervasive games, alternate reality games, or playful design. However, it is not clear how "gamification" relates to these, whether it denotes a novel phenomenon, and how to define it. Thus, in this paper we investigate "gamification" and the historical origins of the term in relation to precursors and similar concepts. It is suggested that "gamified" applications provide insight into novel, gameful phenomena complementary to playful phenomena. Based on our research, we propose a definition of "gamification" as the use of game design elements in non-game contexts.

Advances and open problems in federated learning

Abstract: The term Federated Learning was coined as recently as 2016 to describe a machine learning setting where multiple entities collaborate in solving a machine learning problem, under the coordination of a central server or service provider. Each client’s raw data is stored locally and not exchanged or transferred; instead, focused updates intended for immediate aggregation are used to achieve the learning objective. Since then, the topic has gathered much interest across many different disciplines and the realization that solving many of these interdisciplinary problems likely requires not just machine learning but techniques from distributed optimization, cryptography, security, differential privacy, fairness, compressed sensing, systems, information theory, statistics, and more. This monograph has contributions from leading experts across the disciplines, who describe the latest state-of-the art from their perspective. These contributions have been carefully curated into a comprehensive treatment that enables the reader to understand the work that has been done and get pointers to where effort is required to solve many of the problems before Federated Learning can become a reality in practical systems. Researchers working in the area of distributed systems will find this monograph an enlightening read that may inspire them to work on the many challenging issues that are outlined. This monograph will get the reader up to speed quickly and easily on what is likely to become an increasingly important topic: Federated Learning.

In the Eye of the Beholder: A Survey of Models for Eyes and Gaze

Abstract: Despite active research and significant progress in the last 30 years, eye detection and tracking remains challenging due to the individuality of eyes, occlusion, variability in scale, location, and light conditions. Data on eye location and details of eye movements have numerous applications and are essential in face detection, biometric identification, and particular human-computer interaction tasks. This paper reviews current progress and state of the art in video-based eye detection and tracking in order to identify promising techniques as well as issues to be further addressed. We present a detailed review of recent eye models and techniques for eye detection and tracking. We also survey methods for gaze estimation and compare them based on their geometric properties and reported accuracies. This review shows that, despite their apparent simplicity, the development of a general eye detection technique involves addressing many challenges, requires further theoretical developments, and is consequently of interest to many other domains problems in computer vision and beyond.

Making Social Science Matter

Abstract: If we want to empower and re-enchant social scientific research, we need to do three things. First, we must drop all pretence, however indirect, at emulating the success of the natural sciences in producing cumulative and predictive theory, for their approach simply does not work in any of the social sciences. (For the full argument see Flyvbjerg, 2001.) Second, we must address problems that matter to groups in the local, national and global communities in which we live, and we must do it in ways that matter; we must focus on issues of context, values and power, as advocated by great social scientists from Aristotle and Machiavelli to Max Weber and Pierre Bourdieu. Finally, we must effectively and dialogically communicate the results of our research to our fellow citizens, the ‘public’, and carefully listen to their feedback. If we do this – focus on specific values and interests in the context of particular power relations – we may successfully transform social scientific research into an activity performed in public for publics, sometimes to clarify, sometimes to intervene, sometimes to generate new perspectives, and always to serve as eyes and ears in ongoing efforts to understand the present and to deliberate about the future. We may, in short, arrive at social research that matters.

Cuckoo hashing

Abstract: We present a simple dictionary with worst case constant lookup time, equaling the theoretical performance of the classic dynamic perfect hashing scheme of Dietzfelbinger et al. [SIAM J. Comput. 23 (4) (1994) 738-761]. The space usage is similar to that of binary search trees. Besides being conceptually much simpler than previous dynamic dictionaries with worst case constant lookup time, our data structure is interesting in that it does not use perfect hashing, but rather a variant of open addressing where keys can be moved back in their probe sequences. An implementation inspired by our algorithm, but using weaker hash functions, is found to be quite practical. It is competitive with the best known dictionaries having an average case (but no nontrivial worst case) guarantee on lookup time.