Revisiting Expected Possession Value in Football: Introducing a Benchmark, U-Net Architecture, and Reward and Risk for Passes

TL;DR

This paper develops a new benchmark and an improved EPV model for football, utilizing a U-net architecture and incorporating reward and risk analysis to better evaluate passing decisions and game state values.

Contribution

It introduces the OJN-Pass-EPV benchmark, a novel U-net-based EPV model, and a dual-component pass value model considering reward and risk, advancing football analytics.

Findings

The EPV model correctly identifies higher value states in 78% of pairs.

The U-net architecture improves model loss and calibration error.

The benchmark effectively assesses EPV model quality.

Abstract

This paper introduces the first Expected Possession Value (EPV) benchmark and a new and improved EPV model for football. Through the introduction of the OJN-Pass-EPV benchmark, we present a novel method to quantitatively assess the quality of EPV models by using pairs of game states with given relative EPVs. Next, we attempt to replicate the results of Fern\'andez et al. (2021) using a dataset containing Dutch Eredivisie and World Cup matches. Following our failure to do so, we propose a new architecture based on U-net-type convolutional neural networks, achieving good results in model loss and Expected Calibration Error. Finally, we present an improved pass model that incorporates ball height and contains a new dual-component pass value model that analyzes reward and risk. The resulting EPV model correctly identifies the higher value state in 78% of the game state pairs in the OJN-Pass-EPV benchmark, demonstrating its ability to accurately assess goal-scoring potential. Our findings can help assess the quality of EPV models, improve EPV predictions, help assess potential reward and risk of passing decisions, and improve player and team performance.