The Relationship Between Expected Goals (xG) Based Performance Indicators and Match Outcomes in Elite Football: The 2024–2025 English Premier League Season

Abstract

Aim: This study investigates whether expected goals (xG)–based performance indicators differ systematically across match outcomes in elite football. Method: Match-level data were analyzed using 228 team–match observations (114 fixtures × 2 teams) from league fixtures involving the six teams that finished in the top six positions of the 2024–2025 English Premier League. Performance indicators included expected goals (xG), expected goals against (xGA), expected goals difference (xGD), non-penalty expected goals (npxG), finishing efficiency (goals/xG), total shots, key passes, xG per shot, and non-penalty xG per shot. Match outcome was coded as win (n = 126), draw (n = 54), or loss (n = 48). Assumption checks (normality diagnostics and Levene’s test) were conducted; group differences were examined using one-way ANOVA, followed by Tukey HSD for variables meeting homogeneity and Games–Howell for variables with unequal variances. Effect sizes (partial η²) were reported. Results: Significant group differences were found across all performance variables (all p < .001). Net and process-oriented metrics showed particularly strong discrimination across outcomes, including xGD (partial η² = .197), finishing efficiency (partial η² = .189), and npxG (partial η² = .147). Post-hoc comparisons indicated that wins were consistently associated with stronger offensive production, higher shot quality, and better conversion efficiency, while losses displayed weaker profiles on both attacking and defensive dimensions. Conclusion: Expected goals–based indicators meaningfully differentiate match outcomes among elite teams, supporting the value of process-based metrics for interpreting performance beyond final scorelines.

Keywords

• Expected Goals
• Football
• Goals
• Match Analysis
• Performance

Elit Futbolda Gol Beklentisi (xG) Temelli Performans Göstergeleri ile Maç Sonuçları Arasındaki İlişki: 2024-2025 İngiltere Premier Ligi Sezonu

Abstract

Amaç: Bu çalışma, elit düzeydeki futbolda gol beklentisi (xG) temelli performans göstergelerinin maç sonuçlarına göre sistematik olarak farklılık gösterip göstermediğini incelemektedir. Yöntem: Araştırmada, 2024–2025 İngiltere Premier Ligi’ni ilk altı sırada tamamlayan takımların dahil olduğu 114 müsabakadan (114 fikstür × 2 takım) elde edilen toplam 228 takım-maç gözlemi, maç düzeyinde analiz edilmiştir. Performans göstergeleri; gol beklentisi (xG), kalesinde görülen gol beklentisi (xGA), gol beklentisi farkı (xGD), penaltı dışı gol beklentisi (npxG), bitiricilik verimliliği (gol/xG), toplam şut, anahtar pas, şut başına xG ve şut başına penaltı dışı xG değişkenlerini kapsamaktadır. Maç sonuçları galibiyet (n = 126), beraberlik (n = 54) ve mağlubiyet (n = 48) olarak kodlanmıştır. İstatistiksel analiz öncesinde varsayım kontrolleri (normallik tanılamaları ve Levene testi) gerçekleştirilmiş; gruplar arası farklar tek yönlü ANOVA ile incelenmiştir. Varyansların homojenliği varsayımını karşılayan değişkenler için Tukey HSD, karşılamayanlar için ise Games-Howell post-hoc testleri uygulanmıştır. Etki büyüklükleri (kısmi η²) raporlanmıştır. Bulgular: İncelenen tüm performans değişkenlerinde gruplar arasında anlamlı farklılıklar saptanmıştır (tümü için p < .001). Özellikle xGD (kısmi η² = .197), bitiricilik verimliliği (kısmi η² = .189) ve npxG (kısmi η² = .147) gibi net ve süreç odaklı metriklerin, maç sonuçlarını ayırt etmede yüksek bir güce sahip olduğu görülmüştür. Post-hoc karşılaştırmalar; galibiyetlerin tutarlı bir şekilde daha yüksek hücum üretimi, şut kalitesi ve bitiricilik verimliliği ile ilişkili olduğunu, mağlubiyetlerin ise hem hücum hem de savunma boyutlarında daha zayıf bir profil sergilediğini ortaya koymuştur. Sonuç: Gol beklentisi temelli göstergeler, elit takımlar arasındaki maç sonuçlarını anlamlı düzeyde ayrıştırmaktadır. Bu bulgular, performansın sadece nihai skorlar üzerinden değil, süreç odaklı metrikler üzerinden yorumlanmasının önemini desteklemektedir.

Keywords

• Gol Beklentisi
• Futbol
• Goller
• Müsabaka Analizi
• Performans.

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