Playing Time, Points, and Possession: Evaluating Individual Player Efficiency in the Turkish Basketball League through a Parallel Network SBM Data Envelopment Analysis

Öz

This study applies a parallel non-homogeneous Network Slack-Based Measure Data Envelopment Analysis (NDEA-SBM) model to evaluate the individual efficiency of professional basketball players in the Turkish Basketball League (TBL) across three seasons — 2023–24, 2024–25, and 2025–26. Each player is modelled as a two-stage parallel system in which playing time is simultaneously allocated to offensive and defensive production. The offensive stage converts minutes, field goal attempts, and free throw attempts into points, made field goals, made free throws, and offensive rebounds. The defensive stage converts minutes into defensive rebounds, assists, steals, and blocks, with turnovers incorporated as an undesirable output. For player-season observations in which blocked shots per game equals zero, the corresponding slack term is excluded from the SBM denominator following Tone (2001) and Portela et al. (2004); this correction affects 68 of 300 observations in the defensive stage and prevents score distortion for positionally specialised players. Across 300 player-season observations, the pooled mean overall efficiency is 0.6519, and a persistent structural asymmetry is identified: offensive efficiency (0.7401) consistently exceeds defensive efficiency (0.5637) in every season examined, with the gap reaching 0.2081 in 2025–26. Slack analysis of the 261 inefficient observations identifies unused playing time and offensive rebounding shortfall as the primary sources of offensive inefficiency, while unused court time and defensive rebounding dominate the defensive stage. Super-efficiency analysis differentiates the 39 fully efficient observations. Panel analysis of the 16 players present across all three seasons reveals distinct efficiency trajectories that single-season statistics cannot capture.

Anahtar Kelimeler

• Data Envelopment Analysis
• Network DEA
• Slack-Based Measure
• basketball efficiency
• Turkish Basketball League
• undesirable outputs

Oynama Süresi, Sayı ve Top Hakimiyeti: Paralel Ağ Yapılı SBM Veri Zarflama Analizi ile Türkiye Basketbol Ligi'nde Bireysel Oyuncu Etkinliğinin Değerlendirilmesi

Öz

Bu çalışma, Türkiye Basketbol Ligi'nde (TBL) profesyonel basketbol oyuncularının bireysel etkinliğini 2023–24, 2024–25 ve 2025–26 sezonlarını kapsayan üç yıllık bir dönemde değerlendirmek amacıyla paralel homojen olmayan Ağ Yapılı Artık Temelli Ölçüm Veri Zarflama Analizi (NDEA-SBM) modeli geliştirmektedir. Her oyuncu, oynama süresinin aynı anda hücum ve savunma üretimine tahsis edildiği iki aşamalı paralel bir sistem olarak modellenmektedir. Hücum aşaması; dakika, şut denemesi ve serbest atış denemesini sayı, isabetli şut, isabetli serbest atış ve hücum ribauntuna dönüştürürken savunma aşaması dakikayı savunma ribaundu, asist, top çalma ve blok'a dönüştürmekte; top kayıpları ise istenmeyen çıktı olarak modele dahil edilmektedir. Blok sayısının sıfır olduğu gözlemler için ilgili slack terimi SBM paydasından çıkarılmış; bu düzeltme 300 gözlemin 68'ini kapsamaktadır. 300 oyuncu-sezon gözlemi genelinde havuzlanmış ortalama genel etkinlik 0,6519 olarak hesaplanmış, hücum etkinliği (0,7401) ile savunma etkinliği (0,5637) arasındaki yapısal asimetri her sezonda süreklilik göstermiştir. Slack analizi, hücum aşamasında kullanılmayan oynama süresi ile hücum ribaundu eksikliğini, savunma aşamasında ise kullanılmayan saha süresini ve savunma riboundunu temel verimsizlik kaynakları olarak belirlemiştir. Süper etkinlik analizi 39 tam etkin gözlemi sıralamış; üç sezon boyunca listeye giren 16 oyuncunun panel analizi, tek sezonluk istatistiklerle yakalanamayan bireysel etkinlik yörüngelerini ortaya koymuştur.

Anahtar Kelimeler

• Veri Zarflama Analizi
• Ağ VZA
• Artık Temelli Ölçüm
• basketbol oyuncusu etkinliği
• Türkiye Basketbol Ligi
• istenmeyen çıktılar

Kaynakça

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