TY - JOUR
AB - AbstractDependence Logic was introduced by Jouko Väänänen in 2007. We study a propositional variant of this logic(PDL)and investigate a variety of parameterisations with respect to central decision problems. The model checking problem (MC) ofPDLisNP-complete (Ebbing and Lohmann, SOFSEM 2012). The subject of this research is to identify a list of parameterisations (formula-size, formula-depth, treewidth, team-size, number of variables) under which MC becomes fixed-parameter tractable. Furthermore, we show that the number of disjunctions or the arity of dependence atoms (dep-arity) as a parameter both yield a paraNP-completeness result. Then, we consider the satisfiability problem (SAT) which classically is known to beNP-complete as well (Lohmann and Vollmer, Studia Logica 2013). There we are presenting a different picture: under team-size, or dep-arity SAT isparaNP-complete whereas under all other mentioned parameters the problem isFPT. Finally, we introduce a variant of the satisfiability problem, asking for a team of a given size, and show for this problem an almost complete picture.
AU - Mahmood, Yasir
AU - Meier, Arne
ID - 45849
IS - 2-3
JF - Annals of Mathematics and Artificial Intelligence
KW - Applied Mathematics
KW - Artificial Intelligence
SN - 1012-2443
TI - Parameterised complexity of model checking and satisfiability in propositional dependence logic
VL - 90
ER -
TY - CONF
AU - Kontinen, Juha
AU - Meier, Arne
AU - Mahmood, Yasir
ID - 45846
SN - 0302-9743
T2 - Logical Foundations of Computer Science
TI - A Parameterized View on the Complexity of Dependence Logic
ER -
TY - JOUR
AB - I study a dynamic variant of the DixitâStiglitz (Am Econ Rev 67(3), 1977) model of monopolistic competition by introducing price stickiness à la Fershtman and Kamien (Econometrica 55(5), 1987). The analysis is restricted to bounded quantity and price paths that fulfill the necessary conditions for an open-loop Nash equilibrium. I show that there exists a symmetric steady state and that its stability depends on the degree of product differentiation. When moving from complements to perfect substitutes, the steady state is either a locally asymptotically unstable (spiral) source, a stable (spiral) sink or a saddle point. I further apply the Hopf bifurcation theorem and prove the existence of limit cycles, when passing from a stable to an unstable steady state. Lastly, I provide a numerical example and show that there exists a stable limit cycle.
AU - Hoof, Simon
ID - 45640
IS - 2
JF - Journal of Optimization Theory and Applications
SN - 1573-2878
TI - Dynamic Monopolistic Competition
VL - 189
ER -
TY - GEN
AB - Aggregation metrics in reputation systems are important for overcoming information overload. When using these metrics, technical aggregation functions such as the arithmetic mean are implemented to measure the valence of product ratings. However, it is unclear whether the implemented aggregation functions match the inherent aggregation patterns of customers. In our experiment, we elicit customers' aggregation heuristics and contrast these with reference functions. Our findings indicate that, overall, the arithmetic mean performs best in comparison with other aggregation functions. However, our analysis on an individual level reveals heterogeneous aggregation patterns. Major clusters exhibit a binary bias (i.e., an over-weighting of moderate ratings and under-weighting of extreme ratings) in combination with the arithmetic mean. Minor clusters focus on 1-star ratings or negative (i.e., 1-star and 2-star) ratings. Thereby, inherent aggregation patterns are neither affected by variation of provided information nor by individual characteristics such as experience, risk attitudes, or demographics.
AU - van Straaten, Dirk
AU - Melnikov, Vitalik
AU - Hüllermeier, Eyke
AU - Mir Djawadi, Behnud
AU - Fahr, René
ID - 45616
TI - Accounting for Heuristics in Reputation Systems: An Interdisciplinary Approach on Aggregation Processes
VL - 72
ER -
TY - GEN
AU - van Straaten, Dirk
ID - 45617
TI - Incentive Schemes in Customer Rating Systems - Comparing the Effects of Unconditional and Conditional Rebates on Intrinsic Motivation
VL - 71
ER -
TY - GEN
AU - van Straaten, Dirk
AU - Fahr, René
ID - 45618
TI - Fighting Fire with Fire - Overcoming Ambiguity Aversion by Introducing more Ambiguity
VL - 73
ER -
TY - GEN
AU - Bülling, Jonas
ID - 45788
TI - Political Speaker Transfer: Learning to Generate Text in the Styles of Barack Obama and Donald Trump
ER -
TY - GEN
AU - Mishra, Avishek
ID - 45787
TI - Computational Text Professionalization using Neural Sequence-to-Sequence Models
ER -
TY - CONF
AU - Clausing, Lennart
ID - 30909
T2 - Proceedings of the 11th International Symposium on Highly Efficient Accelerators and Reconfigurable Technologies
TI - ReconOS64: High-Performance Embedded Computing for Industrial Analytics on a Reconfigurable System-on-Chip
ER -
TY - JOUR
AU - Black, Tobias
AU - Fuest, Mario
AU - Lankeit, Johannes
ID - 34673
IS - 3
JF - Zeitschrift für angewandte Mathematik und Physik
KW - Applied Mathematics
KW - General Physics and Astronomy
KW - General Mathematics
SN - 0044-2275
TI - Relaxed parameter conditions for chemotactic collapse in logistic-type parabolic–elliptic Keller–Segel systems
VL - 72
ER -