26 January 2024
09:00 Master's Defense Room 53 of IC2
Theme
Graph-Based Spatio-Temporal Data Analysis for Passing Difficulty Classification in Football
Student
Maisa Silva
Advisor / Teacher
Ricardo da Silva Torres - Co-supervisor: Allan da Silva Pinto
Brief summary
Football, one of the most popular sports in the world, generates billions of dollars annually. The recent availability of equipment for data collection and analysis of football matches made it possible to apply mathematical models. These models allow you to represent and understand how the dynamics of players and teams influence events and match results. Several researches have applied mathematical models to describe the patterns of football matches, evaluate their components and provide crucial information for decision-making by technicians and teams, both to plan strategies for matches and training procedures. One of the most common events in a football match is the pass, which consists of transmitting the ball from a player to another. Many metrics are studied in relation to passing, such as the frequency between two players, the number of successful passes, the accuracy of the pass, among others. At the However, the difficulty of the pass is still a topic little explored in scientific literature. Our study presents an approach to characterize passes at different degrees of Difficulty: easy, medium and difficult. We evaluate which representations are adopted by the elements of the graph (vertices, edges and metrics) are more suitable for modeling the problem. We then compare the impact of greater temporal detail on performance pass classification. Finally, we evaluate whether the fusion of feature vectors influences pass classification performance. The most prominent results include the observation that graphs containing only the team that has possession of the ball are not a good representation for the problem. Furthermore, the best graph representation for binary temporal resolution presents edges for players up to 5 meters away, with degree being the best measure of complex network. In this case, the balanced accuracy reached 61%. For the multilevel evaluation, the best temporal resolution was 20 frames with a bipartite graph configuration, in which the edges represent the interference of the opponent in relation to the target, and the best measure was closeness; this set of vectors of features achieved an accuracy of 65%, the same value as the agreement index of the two labeling technicians. The combination of feature vectors, however, did not present a significant gain in balanced accuracy, reaching a value of 66%. These results suggest that the best feature vectors do not provide views complementary to the classification task.
Examination Board
Headlines:
Allan da Silva Pinto LNLS/CNPEM
Milton Shoiti Misuta FCA/UNICAMP
Bruno Luiz de Souza Bedo EEFE/USP
Substitutes:
Hélio Pedrini IC / UNICAMP
Tiago Guedes Russomanno Technical University of Munich