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Exploring Disease Interactions Using Markov Networks
Haaren, Jan Van (Katholieke Universiteit Leuven) | Davis, Jesse (Katholieke Universiteit Leuven) | Lappenschaar, Martijn (Radboud Universiteit Nijmegen) | Hommersom, Arjen (Radboud Universiteit Nijmegen)
Network medicine is an emerging paradigm for studying the co-occurrence between diseases. While diseases are often interlinked through complex patterns, most of the existing work in this area has focused on studying pairwise relationships between diseases. In this paper, we use a state-of-the-art Markov network learning method to learn interactions between musculoskeletal disorders and cardiovascular diseases and compare this to pairwise approaches. Our experimental results confirm that the sophisticated structure learner produces more accurate models, which can help reveal interesting patterns in the co-occurrence of diseases.
Exploring Disease Interactions Using Markov Networks
Haaren, Jan Van (Katholieke Universiteit Leuven) | Davis, Jesse (Katholieke Universiteit Leuven) | Lappenschaar, Martijn (Radboud Universiteit Nijmegen) | Hommersom, Arjen (Radboud Universiteit Nijmegen)
Network medicine is an emerging paradigm for studying the co-occurrence between diseases. While diseases are often interlinked through complex patterns, most of the existing work in this area has focused on studying pairwise relationships between diseases. In this paper, we use a state-of-the-art Markov network learning method to learn interactions between musculoskeletal disorders and cardiovascular diseases and compare this to pairwise approaches. Our experimental results confirm that the sophisticated structure learner produces more accurate models, which can help reveal interesting patterns in the co-occurrence of diseases.
Exploring Disease Interactions Using Markov Networks
Haaren, Jan Van (Katholieke Universiteit Leuven) | Davis, Jesse (Katholieke Universiteit Leuven) | Lappenschaar, Martijn (Radboud Universiteit Nijmegen) | Hommersom, Arjen (Radboud Universiteit Nijmegen)
Network medicine is an emerging paradigm for studying the co-occurrence between diseases. While diseases are often interlinked through complex patterns, most of the existing work in this area has focused on studying pairwise relationships between diseases. In this paper, we use a state-of-the-art Markov network learning method to learn interactions between musculoskeletal disorders and cardiovascular diseases and compare this to pairwise approaches. Our experimental results confirm that the sophisticated structure learner produces more accurate models, which can help reveal interesting patterns in the co-occurrence of diseases.
Exploring Disease Interactions Using Markov Networks
Haaren, Jan Van (Katholieke Universiteit Leuven) | Davis, Jesse (Katholieke Universiteit Leuven) | Lappenschaar, Martijn (Radboud Universiteit Nijmegen) | Hommersom, Arjen (Radboud Universiteit Nijmegen)
Network medicine is an emerging paradigm for studying the co-occurrence between diseases. While diseases are often interlinked through complex patterns, most of the existing work in this area has focused on studying pairwise relationships between diseases. In this paper, we use a state-of-the-art Markov network learning method to learn interactions between musculoskeletal disorders and cardiovascular diseases and compare this to pairwise approaches. Our experimental results confirm that the sophisticated structure learner produces more accurate models, which can help reveal interesting patterns in the co-occurrence of diseases.
The Baseline Approach to Agent Evaluation
Davidson, Josh (University of Alberta) | Archibald, Christopher (University of Alberta) | Bowling, Michael (University of Alberta)
An important aspect of agent evaluation in stochastic games, especially poker, is the need to reduce the outcome variance in order to get accurate and significant results. The current method used in the Annual Computer Poker Competitionโs analysis is that of duplicate poker, an approach that leverages the ability to deal sets of cards to agents in order to reduce variance. This work explores a different approach to variance reduction by using a control variate based approach known as baseline. The baseline approach involves using an agentโs outcome in self play to create an unbiased estimator for use in agent evaluation and has been shown to work well in both poker and trading agent competition domains. Base- line does not require that the agents are able to be dealt sets of cards, making it a more robust technique than duplicate. This approach is compared to the current duplicate method, as well as other variations of duplicate poker on the results of the 2011 two player no-limit and three player limit Texas Holdโem ACPC tournaments.
On the Social Welfare of Mechanisms for Repeated Batch Matching
Anshelevich, Elliot (Rensselaer Polytechnic Institute) | Chhabra, Meenal (Virginia Tech) | Das, Sanmay (Virginia Tech) | Gerrior, Matthew (GreaneTree Technology)
We study hybrid online-batch matching problems, where agents arrive continuously, but are only matched in periodic rounds, when many of them can be considered simultaneously. Agents not getting matched in a given round remain in the market for the next round. This setting models several scenarios of interest, including many job markets as well as kidney exchange mechanisms. We consider the social utility of two commonly used mechanisms for such markets: one that aims for stability in each round (greedy), and one that attempts to maximize social utility in each round (max-weight). Surprisingly, we find that in the long term, the social utility of the greedy mechanism can be higher than that of the max-weight mechanism. We hypothesize that this is because the greedy mechanism behaves similarly to a soft threshold mechanism, where all connections below a certain threshold are rejected by the participants in favor of waiting until the next round. Motivated by this observation, we propose a method to approximately calculate the optimal threshold for an individual agent to use based on characteristics of the other agents participating, and demonstrate experimentally that social utility is high when all agents use this strategy. Thresholding can also be applied by the mechanism itself to improve social welfare; we demonstrate this with an example on graphs that model pairwise kidney exchange.
Strategic Behavior when Allocating Indivisible Goods Sequentially
Kalinowski, Thomas (University of Rostock) | Narodytska, Nina (NICTA and University of New South Wales) | Walsh, Toby (NICTA and University of New South Wales) | Xia, Lirong (Harvard University)
We study a simple sequential allocation mechanism for allocating indivisible goods between agents in which agents take turns to pick items.We focus on agents behaving strategically. We view the allocation procedure as a finite repeated game with perfect information. We show that with just two agents, we can compute the unique subgame perfect Nash equilibrium in linear time. With more agents, computing the subgame perfect Nash equilibria is more difficult. There can be an exponential number of equilibria and computing even one of them is PSPACE-hard. We identify a special case, when agents value many of the items identically, where we can efficiently compute the subgame perfect Nash equilibria. We also consider the effect of externalities and modifications to the mechanism that make it strategy proof.
Progression of Decomposed Situation Calculus Theories
Ponomaryov, Denis (University of Ulm) | Soutchanski, Mikhail (Ryerson University)
In many tasks related to reasoning about consequences of a logical theory, it is desirable to decompose the theory into a number of components with weakly-related or independent signatures. This facilitates reasoning when signature of a query formula belongs to only one of the components. However, an initial theory may be subject to change due to execution of actions affecting features mentioned in the theory. Having once computed a decomposition of a theory, one would like to know whether a decomposition has to be computed again for the theory obtained from taking into account the changes resulting from execution of an action. In the paper, we address this problem in the scope of the situation calculus, where change of an initial theory is related to the well-studied notion of progression. Progression provides a form of forward reasoning; it relies on forgetting values of those features which are subject to change and computing new values for them. We prove new results about properties of decomposition components under forgetting and show when a decomposition can be preserved in progression of an initial theory.
From Semantic to Emotional Space in Probabilistic Sense Sentiment Analysis
Mohtarami, Mitra (National University of Singapore) | Lan, Man (Institute for Infocomm Research) | Tan, Chew Lim (National University of Singapore)
This paper proposes an effective approach to model the emotional space of words to infer their Sense Sentiment Similarity (SSS). SSS reflects the distance between the words regarding their senses and underlying sentiments. We propose a probabilistic approach that is built on a hidden emotional model in which the basic human emotions are considered as hidden. This leads to predict a vector of emotions for each sense of the words, and then to infer the sense sentiment similarity. The effectiveness of the proposed approach is investigated in two Natural Language Processing tasks: Indirect yes/no Question Answer Pairs Inference and Sentiment Orientation Prediction.
PAC Optimal Exploration in Continuous Space Markov Decision Processes
Pazis, Jason (Duke University) | Parr, Ronald (Duke University)
Current exploration algorithms can be classified in two broad categories: Heuristic, and PAC optimal. While numerous researchers have used heuristic approaches such as epsilon-greedy exploration successfully, such approaches lack formal, finite sample guarantees and may need a significant amount of fine-tuning to produce good results. PAC optimal exploration algorithms, on the other hand, offer strong theoretical guarantees but are inapplicable in domains of realistic size. The goal of this paper is to bridge the gap between theory and practice, by introducing C-PACE, an algorithm which offers strong theoretical guarantees and can be applied to interesting, continuous space problems.