Technology
Equilibrium Refinement through Negotiation in Binary Voting
Grandi, Umberto (IRIT, University of Toulouse) | Grossi, Davide (University of Liverpool) | Turrini, Paolo (Imperial College London)
We study voting games on binary issues, where voters might hold an objective over some issues at stake, while willing to strike deals on the remaining ones, and can influence one anotherโs voting decision before the vote takes place. We analyse votersโ rational behaviour in the resulting two-phase game, showing under what conditions undesirable equilibria can be removed as an effect of the pre-vote phase.
Implementing the Wisdom of Waze
Vasserman, Shoshana (Harvard University) | Feldman, Michal (Tel-Aviv University) | Hassidim, Avinatan (Bar Ilan University, Google)
We study a setting of non-atomic routing in a network of m parallel links with asymmetry of information. While a central entity (such as a GPS navigation system) โ a mediator hereafter โ knows the cost functions associated with the links, they are unknown to the individual agents controlling the flow. The mediator gives incentive compatible recommendations to agents, trying to minimize the total travel time. Can the mediator do better than when agents minimize their travel time selfishly without coercing agents to follow his recommendations? We study the mediation ratio: the ratio between the mediated equilibrium obtained from an incentive compatible mediation protocol and the social optimum. We find that mediation protocols can reduce the efficiency loss compared to the full revelation alternative, and compared to the non mediated Nash equilibrium. In particular, in the case of two links with affine cost functions, the mediation ratio is at most 8/7, and remains strictly smaller than the price of anarchy of 4/3 for any fixed m. Yet, it approaches the price of anarchy as m grows. For general (monotone) cost functions, the mediation ratio is at most m, a significant improvement over the unbounded price of anarchy
Multi-Label Active Learning: Query Type Matters
Huang, Sheng-Jun (Nanjing University of Aeronautics and Astronautics) | Chen, Songcan (Nanjing University of Aeronautics and Astronautics) | Zhou, Zhi-Hua (Nanjing University)
Active learning reduces the labeling cost by selectively querying the most valuable information from the annotator. It is essentially important for multi-label learning, where the labeling cost is rather high because each object may be associated with multiple labels. Existing multi-label active learning (MLAL) research mainly focuses on the task of selecting instances to be queried. In this paper, we disclose for the first time that the query type, which decides what information to query for the selected instance, is more important. Based on this observation, we propose a novel MLAL framework to query the relevance ordering of label pairs, which gets richer information from each query and requires less expertise of the annotator. By incorporating a simple selection strategy and a label ranking model into our framework, the proposed approach can reduce the labeling effort of annotators significantly. Experiments on 20 benchmark datasets and a manually labeled real data validate that our approach not only achieves superior performance on classification, but also provides accurate ranking for relevant labels.
Tractable Classes of Binary CSPs Defined by Excluded Topological Minors
Cohen, David A. (Royal Holloway, University of London) | Cooper, Martin C. (IRIT, University of Toulouse) | Jeavons, Peter G (University of Oxford) | Zivny, Stanislav (University of Oxford)
The binary Constraint Satisfaction Problem (CSP) is to decide whether there exists an assignment to a set of variables which satisfies specified constraints between pairs of variables. A CSP instance can be presented as a labelled graph (called the microstructure) encoding both the forms of the constraints and where they are imposed. We consider subproblems defined by restricting the allowed form of the microstructure. One form of restriction that has previously been considered is to forbid certain specified substructures (patterns). This captures some tractable classes of the CSP, but does not capture the well-known property of acyclicity. In this paper we introduce the notion of a topological minor of a binary CSP instance. By forbidding certain patterns as topological minors we obtain a compact mechanism for expressing several novel tractable classes, including new generalisations of the class of acyclic instances.
The Logic of Qualitative Probability
Delgrande, James (Simon Fraser University) | Renne, Bryan (University of Amsterdam)
In this paper we present a theory of qualitative probability. Work in the area goes back at least to de Finetti. The usual approach is to specify a binary operator โผ with ฯ โผ ฯ having the intended interpretation that ฯ is not more probable than ฯ . We generalise these approaches by extending the domain of the operator โผ from the set of events to the set of finite sequences of events. If ฮฆ and ฮจ are finite sequences of events, ฮฆ โผ ฮจ has the intended interpretation that the summed probabilities of the elements of ฮฆ is not greater than the sum of those of ฮจ . We provide a sound and complete axiomatisation for this operator over finite outcome sets, and show that this theory is sufficiently powerful to capture the results of axiomatic probability theory. We argue that our approach is simpler and more perspicuous than previous accounts. As well, we prove that our approach generalises the two major accounts for finite outcome sets.
Cognitive Modelling for Predicting Examinee Performance
Wu, Runze (University of Science and Technology of China) | Liu, Qi (University of Science and Technology of China) | Liu, Yuping (University of Science and Technology of China) | Chen, Enhong (University of Science and Technology of China) | Su, Yu (Anhui USTC iFLYTEK Co., Ltd.) | Chen, Zhigang (Anhui USTC iFLYTEK Co., Ltd., China) | Hu, Guoping (Anhui USTC iFLYTEK Co., Ltd., China)
Cognitive modelling can discover the latent characteristics of examinees for predicting their performance (i.e. scores) on each problem. As cognitive modelling is important for numerous applications, e.g. personalized remedy recommendation, some solutions have been designed in the literature. However, the problem of extracting information from both objective and subjective problems to get more precise and interpretable cognitive analysis is still underexplored. To this end, we propose a fuzzy cognitive diagnosis framework (FuzzyCDF) for examinees' cognitive modelling with both objective and subjective problems. Specifically, to handle the partially correct responses on subjective problems, we first fuzzify the skill proficiency of examinees. Then, we combine fuzzy set theory and educational hypotheses to model the examinees' mastery on the problems. Further, we simulate the generation of examination scores by considering both slip and guess factors. Extensive experiments on three real-world datasets prove that FuzzyCDF can predict examinee performance more effectively, and the output of FuzzyCDF is also interpretative.
Finite Abstractions for the Verification of Epistemic Properties in Open Multi-Agent Systems
Belardinelli, Francesco (Universitรฉ d'Evry) | Grossi, Davide (University of Liverpool) | Lomuscio, Alessio (Imperial College London)
We develop a methodology to model and verify Regarding the second limitation, proposals have been put open multi-agent systems (OMAS), where agents forward to consider a set of objects that vary at design time; may join in or leave at run time. Further, we specify the set of agents is normally considered to be finite in each properties of interest on OMAS in a variant of firstorder system run. This is a sensible assumption in many scenarios, temporal-epistemic logic, whose characterising but there are applications of MAS (e.g., e-commerce, smart features include epistemic modalities indexed grids) where an unbounded number of agents may freely enter to individual terms, interpreted on agents appearing and leave the system at run time. There is, therefore, at a given state. This formalism notably allows a need to account for the unbounded and possibly infinite to express group knowledge dynamically. We study agents joining in or leaving an open MAS. In this setting it the verification problem of these systems and show is still of interest to reason about their evolution and what that, under specific conditions, finite bisimilar abstractions they know individually and collectively. For example, in an can be obtained.
Mining Expert Play to Guide Monte Carlo Search in the Opening Moves of Go
Steinmetz, Erik S. (University of Minnesota) | Gini, Maria (University of Minnesota)
We propose a method to guide a Monte Carlo search in the initial moves of the game of Go. Our method matches the current state of a Go board against clusters of board configurations that are derived from a large number of games played by experts. The main advantage of this method is that it does not require an exact match of the current board, and hence is effective for a longer sequence of moves compared to traditional opening books. We apply this method to two different open-source Go-playing programs. Our experiments show that this method, through its filtering or biasing the choice of a next move to a small subset of possible moves, improves play effectively in the initial moves of a game.
Impartial Peer Review
Kurokawa, David (Carnegie Mellon University) | Lev, Omer (Hebrew University of Jerusalem) | Morgenstern, Jamie (Carnegie Mellon University) | Procaccia, Ariel D. (Carnegie Mellon University)
Motivated by a radically new peer review system that the National Science Foundation recently experimented with, we study peer review systems in which proposals are reviewed by PIs who have submitted proposals themselves. An (m,k)-selection mechanism asks each PI to review m proposals, and uses these reviews to select (at most) k proposals. We are interested in impartial mechanisms, which guarantee that the ratings given by a PI to others' proposals do not affect the likelihood of the PI's own proposal being selected. We design an impartial mechanism that selects a k-subset of proposals that is nearly as highly rated as the one selected by the non-impartial (abstract version of) the NSF pilot mechanism, even when the latter mechanism has the "unfair" advantage of eliciting honest reviews.