27 research outputs found
構造化データに対する予測手法:グラフ,順序,時系列
京都大学新制・課程博士博士(情報学)甲第23439号情博第769号新制||情||131(附属図書館)京都大学大学院情報学研究科知能情報学専攻(主査)教授 鹿島 久嗣, 教授 山本 章博, 教授 阿久津 達也学位規則第4条第1項該当Doctor of InformaticsKyoto UniversityDFA
Modelling intransitivity in pairwise comparisons with application to baseball data
In most commonly used ranking systems, some level of underlying transitivity
is assumed. If transitivity exists in a system then information about pairwise
comparisons can be translated to other linked pairs. For example, if typically
A beats B and B beats C, this could inform us about the expected outcome
between A and C. We show that in the seminal Bradley-Terry model knowing the
probabilities of A beating B and B beating C completely defines the probability
of A beating C, with these probabilities determined by individual skill levels
of A, B and C. Users of this model tend not to investigate the validity of this
transitive assumption, nor that some skill levels may not be statistically
significantly different from each other; the latter leading to false
conclusions about rankings. We provide a novel extension to the Bradley-Terry
model, which accounts for both of these features: the intransitive
relationships between pairs of objects are dealt with through interaction terms
that are specific to each pair; and by partitioning the skills into
distinct clusters, any differences in the objects' skills become
significant, given appropriate . With competitors there are
interactions, so even in multiple round robin competitions this gives too many
parameters to efficiently estimate. Therefore we separately cluster the
values of intransitivity into clusters, giving
estimatable values respectively, typically with . Using a Bayesian
hierarchical model, are treated as unknown, and inference is conducted
via a reversible jump Markov chain Monte Carlo (RJMCMC) algorithm. The model is
shown to have an improved fit out of sample in both simulated data and when
applied to American League baseball data.Comment: 26 pages, 7 figures, 2 tables in the main text. 17 pages in the
supplementary materia
Principal Trade-off Analysis
How are the advantage relations between a set of agents playing a game
organized and how do they reflect the structure of the game? In this paper, we
illustrate "Principal Trade-off Analysis" (PTA), a decomposition method that
embeds games into a low-dimensional feature space. We argue that the embeddings
are more revealing than previously demonstrated by developing an analogy to
Principal Component Analysis (PCA). PTA represents an arbitrary two-player
zero-sum game as the weighted sum of pairs of orthogonal 2D feature planes. We
show that the feature planes represent unique strategic trade-offs and
truncation of the sequence provides insightful model reduction. We demonstrate
the validity of PTA on a quartet of games (Kuhn poker, RPS+2, Blotto, and
Pokemon). In Kuhn poker, PTA clearly identifies the trade-off between bluffing
and calling. In Blotto, PTA identifies game symmetries, and specifies strategic
trade-offs associated with distinct win conditions. These symmetries reveal
limitations of PTA unaddressed in previous work. For Pokemon, PTA recovers
clusters that naturally correspond to Pokemon types, correctly identifies the
designed trade-off between those types, and discovers a rock-paper-scissor
(RPS) cycle in the Pokemon generation type - all absent any specific
information except game outcomes.Comment: 17 pages, 8 figure
CrowDEA: Multi-view Idea Prioritization with Crowds
Given a set of ideas collected from crowds with regard to an open-ended
question, how can we organize and prioritize them in order to determine the
preferred ones based on preference comparisons by crowd evaluators? As there
are diverse latent criteria for the value of an idea, multiple ideas can be
considered as "the best". In addition, evaluators can have different preference
criteria, and their comparison results often disagree.
In this paper, we propose an analysis method for obtaining a subset of ideas,
which we call frontier ideas, that are the best in terms of at least one latent
evaluation criterion. We propose an approach, called CrowDEA, which estimates
the embeddings of the ideas in the multiple-criteria preference space, the best
viewpoint for each idea, and preference criterion for each evaluator, to obtain
a set of frontier ideas. Experimental results using real datasets containing
numerous ideas or designs demonstrate that the proposed approach can
effectively prioritize ideas from multiple viewpoints, thereby detecting
frontier ideas. The embeddings of ideas learned by the proposed approach
provide a visualization that facilitates observation of the frontier ideas. In
addition, the proposed approach prioritizes ideas from a wider variety of
viewpoints, whereas the baselines tend to use to the same viewpoints; it can
also handle various viewpoints and prioritize ideas in situations where only a
limited number of evaluators or labels are available.Comment: Accepted in HCOMP 202
Analysis of Matchmaking Optimization Systems Potential in Mobile eSports
Matchmaking systems are one of the core features of experience in online gaming. They influence player satisfaction, engagement, and churn risk. The paper looks into the current state of the theoretical and practical implementation of such systems in the mobile gaming industry. We propose a basic classification of matchmaking systems into random and quasi-random, skill-based, role-based, technical factor-based, and engagement based. We also offer an analysis of matchmaking systems in 16 leading mobile Esport games. The dominant industry solution is skill and rank based systems with a different level of skill depth measurement. In the further part of the paper, we present a theoretical model of engagement and a time-optimized model
Mason: Real-time NBA Matches Outcome Prediction
abstract: The National Basketball Association (NBA) is the most popular basketball league in the world. The world-wide mighty high popularity to the league leads to large amount of interesting and challenging research problems. Among them, predicting the outcome of an upcoming NBA match between two specific teams according to their historical data is especially attractive. With rapid development of machine learning techniques, it opens the door to examine the correlation between statistical data and outcome of matches. However, existing methods typically make predictions before game starts. In-game prediction, or real-time prediction, has not yet been sufficiently studied. During a match, data are cumulatively generated, and with the accumulation, data become more comprehensive and potentially embrace more predictive power, so that prediction accuracy may dynamically increase with a match goes on. In this study, I design game-level and player-level features based on realtime data of NBA matches and apply a machine learning model to investigate the possibility and characteristics of using real-time prediction in NBA matches.Dissertation/ThesisMasters Thesis Computer Science 201