Journal of Sports Analytics - Volume 6, issue 4

Authors: Daly-Grafstein, Daniel | Bornn, Luke

Article Type: Research Article

Abstract: As 3-point shooting in the NBA continues to increase, the importance of perimeter defense has never been greater. Perimeter defenders are often evaluated by their ability to tightly contest shots, but how exactly does contesting a jump shot cause a decrease in expected shooting percentage, and can we use this insight to better assess perimeter defender ability? In this paper we analyze over 50,000 shot trajectories from the NBA to explain why, in terms of impact on shot trajectories, shooters tend to miss more when tightly contested. We present a variety of results derived from this shot trajectory data. Additionally, …pairing trajectory data with features such as defender height, distance, and contest angle, we are able to evaluate not just perimeter defenders, but also shooters’ resilience to defensive pressure. Utilizing shot trajectories and corresponding modeled shot-make probabilities, we are able to create perimeter defensive metrics that are more accurate and less variable than traditional metrics like opponent field goal percentage. Show more

Keywords: Basketball, Rao-Blackwell theorem, optical tracking, variance reduction

DOI: 10.3233/JSA-200400

Citation: Journal of Sports Analytics, vol. 6, no. 4, pp. 235-242, 2020

Authors: Wolf, Stephan | Schmitt, Maximilian | Schuller, Björn

Article Type: Research Article

Abstract: Association football (soccer) is the most popular sport in the world, resulting in a large economic interest from investors, team managers, and betting agencies. For this reason, a vast number of rating systems exists to assess the strength of football teams or individual players. Nevertheless, most of the existing approaches incorporate deficiencies, e. g., that they depend on subjective ratings from experts. The objective of this work was the development of a new rating system for determining the playing strength of football players. The Elo algorithm, which has established itself as an objective and adaptive rating system in numerous individual sports, …has been expanded in accordance with the requirements of team sports. Matches from 16 different European domestic leagues, the UEFA Champions and Europa Leagues have been recorded, with more than 17 000 matches played in recent years, and 12 400 different players. The developed rating system produced promising results, when evaluating the matches based on its predictions. A high relevance of the created system results from the fact that only the associated match report is needed and thus—in relation to existing valuation models—significantly more football players can be assessed. Show more

Keywords: Football, soccer, rating system, elo algorithm, player performance

DOI: 10.3233/JSA-200411

Citation: Journal of Sports Analytics, vol. 6, no. 4, pp. 243-257, 2020

Authors: Guyon, Julien

Article Type: Research Article

Abstract: In 2026, the FIFA World Cup will for the first time gather 48 men’s national teams. It will consist of a group stage made of 16 groups of three, with the best two teams in each group advancing to the knockout stage. Using groups of three raises several fairness issues, including the risk of match fixing and schedule imbalance. In this article we examine the risk of collusion. The two teams who play the last game in the group know exactly what results will let them advance to the knockout stage. Risk of match fixing occurs when a result qualifies …both of them at the expense of the third team of the group, and can seriously tarnish the tournament. We quantify how often this is expected to happen and explain how to build the match schedule so as to minimize the risk of collusion. We also quantify how the risk of collusion depends on competitive balance. Moreover, we show that forbidding draws during the group stage (a rule considered by FIFA) does not eliminate the risk of match fixing, and that, surprisingly, the 3-2-1-0 point system does not do a better job at decreasing the risk of collusion than the 3-0 point system. Finally we describe alternate formats for a 48-team World Cup that would eliminate or strongly decrease the risk of collusion. Show more

Keywords: Sports, tournament design, FIFA World Cup, groups of three, match fixing, collusion, point system

DOI: 10.3233/JSA-200414

Citation: Journal of Sports Analytics, vol. 6, no. 4, pp. 259-279, 2020

Authors: Bouzarth, Elizabeth L. | Cromer, Andrew W. | Fravel, William J. | Grannan, Benjamin C. | Hutson, Kevin R.

Article Type: Research Article

Abstract: The National Football League (NFL) schedules regular season games so that some matchups are based on the previous year’s results. Since team composition changes from year to year, this scheduling policy creates variation in teams’ strength of schedules and sometimes benefits teams unfairly, allowing some an easier path to the playoffs than others. This paper proposes methods to produce an NFL schedule that combine some of its traditional elements with dynamically scheduled games aimed at optimizing different objectives, such as reducing the variability of teams’ strength of schedule or minimizing the number of pairwise comparisons needed to differentiate team quality …so as to make each teams’ regular season schedule as fair as possible. Show more

DOI: 10.3233/JSA-200428

Citation: Journal of Sports Analytics, vol. 6, no. 4, pp. 281-293, 2020

Authors: Manage, Ananda B. W. | Kafle, Ram C. | Wijekularathna, Danush K.

Article Type: Research Article

Abstract: In cricket, all-rounders play an important role. A good all-rounder should be able to contribute to the team by both bat and ball as needed. However, these players still have their dominant role by which we categorize them as batting all-rounders or bowling all-rounders. Current practice is to do so by mostly subjective methods. In this study, the authors have explored different machine learning techniques to classify all-rounders into bowling all-rounders or batting all-rounders based on their observed performance statistics. In particular, logistic regression, linear discriminant function, quadratic discriminant function, naïve Bayes, support vector machine, and random forest classification methods …were explored. Evaluation of the performance of the classification methods was done using the metrics accuracy and area under the ROC curve. While all the six methods performed well, logistic regression, linear discriminant function, quadratic discriminant function, and support vector machine showed outstanding performance suggesting that these methods can be used to develop an automated classification rule to classify all-rounders in cricket. Given the rising popularity of cricket, and the increasing revenue generated by the sport, the use of such a prediction tool could be of tremendous benefit to decision-makers in cricket. Show more

Keywords: Classification, machine learning, statistical learning, cricket, all-rounders, ranking

DOI: 10.3233/JSA-200467

Citation: Journal of Sports Analytics, vol. 6, no. 4, pp. 295-306, 2020