Helsinki Institute for Information Technology

About: Helsinki Institute for Information Technology is a facility organization based out in Espoo, Finland. It is known for research contribution in the topics: Population & Bayesian network. The organization has 630 authors who have published 1962 publications receiving 63426 citations.

Cloud Computing: Centralization and Data Sovereignty

Abstract: Cloud computing can be defined as the provision of computing resources on-demand over the Internet. Although this might bring a number of advantages to end-users in terms of accessibility and elasticity of costs, problems arise concerning the collection of personal information in the Cloud and the legitimate exploitation thereof. To the extent that most of the content and software application are only accessible online, users have no longer control over the manner in which they can access their data and the extent to which third parties can exploit it.

The Answer Set Programming Paradigm

Abstract: In this article, we give an overview of the answer set programming paradigm, explain its strengths, and illustrate its main features in terms of examples and an application problem.

Not being (super)thin or solid is hard: A study of grid Hamiltonicity

Abstract: We give a systematic study of Hamiltonicity of grids - the graphs induced by finite subsets of vertices of the tilings of the plane with congruent regular convex polygons (triangles, squares, or hexagons). Summarizing and extending existing classification of the usual, ''square'', grids, we give a comprehensive taxonomy of the grid graphs. For many classes of grid graphs we resolve the computational complexity of the Hamiltonian cycle problem. For graphs for which there exists a polynomial-time algorithm we give efficient algorithms to find a Hamiltonian cycle. We also establish, for any g>=6, a one-to-one correspondence between Hamiltonian cycles in planar bipartite maximum-degree-3 graphs and Hamiltonian cycles in the class C"g of girth-g planar maximum-degree-3 graphs. As applications of the correspondence, we show that for graphs in C"g the Hamiltonian cycle problem is NP-complete and that for any N>=5 there exist graphs in C"g that have exactly N Hamiltonian cycles. We also prove that for the graphs in C"g, a Chinese Postman tour gives a (1+8g)-approximation to TSP, improving thereby the Christofides ratio when g>16. We show further that, in any graph, the tour obtained by Christofides' algorithm is not longer than a Chinese Postman tour.

Sticky Tunes: How Do People React to Involuntary Musical Imagery?

Abstract: The vast majority of people experience involuntary musical imagery (INMI) or ‘earworms’; perceptions of spontaneous, repetitive musical sound in the absence of an external source. The majority of INMI episodes are not bothersome, while some cause disruption ranging from distraction to anxiety and distress. To date, little is known about how the majority of people react to INMI, in particular whether evaluation of the experience impacts on chosen response behaviours or if attempts at controlling INMI are successful or not. The present study classified 1046 reports of how people react to INMI episodes. Two laboratories in Finland and the UK conducted an identical qualitative analysis protocol on reports of INMI reactions and derived visual descriptive models of the outcomes using grounded theory techniques. Combined analysis carried out across the two studies confirmed that many INMI episodes were considered neutral or pleasant, with passive acceptance and enjoyment being among the most popular response behaviours. A significant number of people, however, reported on attempts to cope with unwanted INMI. The most popular and effective behaviours in response to INMI were seeking out the tune in question, and musical or verbal distraction. The outcomes of this study contribute to our understanding of the aetiology of INMI, in particular within the framework of memory theory, and present testable hypotheses for future research on successful INMI coping strategies.