Actions Speak Louder Than Goals: Valuing Player Actions in Soccer

Assessing the impact of the individual actions performed by soccer players during games is a crucial aspect of the player recruitment process. Unfortunately, most traditional metrics fall short in addressing this task as they either focus on rare actions like shots and goals alone or fail to account for the context in which the actions occurred. This paper introduces (1) a new language for describing individual player actions on the pitch and (2) a framework for valuing any type of player action based on its impact on the game outcome while accounting for the context in which the action happened. By aggregating soccer players' action values, their total offensive and defensive contributions to their team can be quantified. We show how our approach considers relevant contextual information that traditional player evaluation metrics ignore and present a number of use cases related to scouting and playing style characterization in the 2016/2017 and 2017/2018 seasons in Europe's top competitions.Comment: Significant update of the paper. The same core idea, but with a clearer methodology, applied on a different data set, and more extensive experiments. 9 pages + 2 pages appendix. To be published at SIGKDD 201

Reconsideration of the Best Batting Order in Baseball: Is the Order to Maximize the Expected Number of Runs Really the Best?

In previous studies for analyzing the batting order of baseball games, the order is evaluated by its expected number of runs scored in a game, under the Markov chain model on the DEsopo and Lefkowitz runner advancement model. However, the order to maximize the expected number of runs may not be the best order in the sense that it may not get more than 0.5 in probability of winning the game against other possible batting orders. In this sense, the best batting order is reconsidered, and it is tried to find better orders than the order which maximizes the expected number of runs. In this paper, the existence of such orders and the difference between the best orders and the order to maximize the expected number of runs are concretely shown by taking into account of not only the expected number of runs but also the standard deviation of runs, based on the data of Major League teams.

Modeling Tactical Changes of Formation in Association Football as a Zero-Sum Game

Although tactical decisions made by managers during a match of team sports are very important, there have been few quantitative analyses which include the effect of interaction between both teams decisions, because of the complexity of the problem where one teams decision will affect the other teams. A game theoretic approach can be useful for tackling this type of problem.This paper proposes a game theoretic approach to modeling tactical changes of formation in an association football match. We assume probabilities of scoring and conceding a goal follow Poisson distributions and use a regression model to evaluate the means of the distributions. These means represent the offensive strength for scoring a goal and defensive propensity to concede a goal in terms of a teams formation, i.e. a combination of the number of each type of outfield player on the pitch, and are estimated by means of the maximum likelihood method. We then develop a mathematical formulation with which we can calculate the probability of the home team winning the match, and use it to analyse tactical changes of the teams formations, modeling the football match as a zero-sum game, in which the gain in probability of one team winning is equal to the loss in probability of the other team winning. We demonstrate how the managers decisions affect the probability of winning the match using real data of the Japan professional football league, by showing four cases of the quality of both managers decisions, depending on whether they each use their best or worst strategies.There still remains some uncertainty and longer observational studies will be required for a complete analysis, but this method can help to evaluate quantitatively the quality of tactical decisions made by managers.

Evaluation of Individual and Team Judo Strengths Using AHP Technique and Team Competition Data

This study aimed to evaluate individual and team judo strengths using an analytic hierarchy process (AHP). The source of the decision was based only upon the international regulation values assigned to each of the decisive technique: 10 points for an ippon, 7 for a waza-ari and 5 for yuko(s). The data were obtained from Japans interscholastic athletic competition for mens judo (high school teams) in 2005. Our AHP technique demonstrated an ability to predict judo strengths of individual players, and to detect potential players regardless of unsuccessful team results. There was a significant but small correlation between the actual team rankings and predicted team strengths. The predicted team strengths, however, may be more informative and appropriate to evaluate judo strengths than the tournament results, as they were based on the content of each individual match, rather than just win/lose results. Coaches or talent scouts should consider the estimated individual or team strengths as well as competition results to make more accurate decisions when selecting players or teams.

Modeling Tactical Changes of Formation in Association Football as a Non-Zero-Sum Game

In football leagues, a won match produces three points (all for the winner) whereas a drawn match produces only two (one for each team). Here, the total resource from the viewpoint of league points is not constant and the gain of the match for both teams changes depending on the result of the match. To cater for this situation, we propose a formulation for modelling tactical changes of formation in an association football match as a non-zero-sum game using game theory. In this paper, we focus on two well-known teams in the J. League and analyse their offensive and defensive strengths based on their formation, i.e., a combination of the number of each type of outfield player on the pitch. Using these estimated offensive and defensive strengths, we develop the mathematical formulation for analyzing tactical changes of these teams' formations from the viewpoint to increase their expected number of league points gained in a match, and quantitatively demonstrate not only the effect of the introduction of the league point system on the tactical change, but also the effect of cooperation between managers which could make both teams benefit in terms of the expected number of league points gained in a match.

The fabrication of Ni quantum cross devices with a 17 nm junction and their current-voltage characteristics

Quantum cross (QC) devices which consist of two Ni thin films deposited on polyethylene naphthalate (PEN) substrates with their edges crossing have been fabricated and its current-voltage characteristics have been investigated. The cross-sectional area between the two Ni electrodes, which was made without the use of electron-beam or optical lithography, is as small as 17 nm x 17 nm. We have successfully obtained ohmic current-voltage characteristics, which show good agreement with calculation results within the framework of modified Anderson model. The calculated results also predict a high switching ratio in excess of 100000:1 for QC devices having the molecule sandwiched between the Ni electrodes. This indicates that QC devices having the molecule can be expected to have potential application in novel switching devices

Fabrication and Current-Voltage Characteristics of Ni Spin Quantum Cross Devices with P3HT:PCBM Organic Materials

We have proposed spin quantum cross (SQC) devices, in which organic materials are sandwiched between two edges of magnetic thin films whose edges are crossed, towards the realization of novel beyond-CMOS switching devices. In SQC devices, nanometer-size junctions can be produced since the junction area is determined by the film thickness. In this study, we have fabricated Ni SQC devices with poly-3-hexylthiophene (P3HT): 6, 6-phenyl C61-butyric acid methyl ester (PCBM) organic materials and investigated the current-voltage (I-V) characteristics experimentally and theoretically. As a result of I-V measurements, ohmic I-V characteristics have been obtained at room temperature for Ni SQC devices with P3HT:PCBM organic materials, where the junction area is as small as 16 nm x 16 nm. This experimental result shows quantitative agreement with the theoretical calculation results performed within the framework of the Anderson model under the strong coupling limit. Our calculation also shows that a high on/off ratio beyond 10000:1 can be obtained in Ni SQC devices with P3HT:PCBM organic materials under the weak coupling condition

Expression, purification and preliminary X-ray characterization of dl-2-haloacid dehalogenase from Methylobacterium sp. CPA1

A recombinant form of dl-2-haloacid dehalogenase from Methylobacterium sp. CPA1 has been expressed in E. coli, purified and crystallized. The crystal belongs to space group P63. Diffraction data have been collected to 1.75 Å resolution