EVALUATING OPERATIONAL AND FINANCIAL EFFICIENCY IN THE CIVIL AVIATION SECTOR USING NETWORK DATA ENVELOPMENT ANALYSIS: A TURKEY ANALYSIS DURING THE COVID-19 PERIOD

Öz

This study evaluates the operational and financial efficiency of five airline companies in the Turkish civil aviation sector during 2019-2023 using two-stage network data envelopment analysis. The first stage measures the efficiency of converting operational inputs into flight production, while the second stage assesses the conversion of operational outputs into financial ratios. Shannon entropy for objective weighting, fuzzy logic for uncertainty modeling, and translation invariance for negative value transformation were employed. Results show that operational efficiency average (0.886) is higher than financial efficiency (0.681). Only 16 percent of decision-making units are fully efficient in both stages. The COVID-19 pandemic caused a 65 percent decrease in financial efficiency in 2020, but the sector exceeded pre-pandemic levels in 2023, demonstrating strong recovery capacity. Friedman test found year differences statistically significant (p=0.003). The study provides methodological contributions and targeted managerial recommendations for firms.

Anahtar Kelimeler

• Network Data Envelopment Analysis
• airline efficiency
• financial performance
• COVID-19

SİVİL HAVACILIK SEKTÖRÜNDE OPERASYONEL VE FİNANSAL ETKİNLİĞİN AĞ YAPILI VERİ ZARFLAMA ANALİZİ İLE DEĞERLENDİRİLMESİ: COVID-19 DÖNEMİ TÜRKİYE ANALİZİ

Öz

Bu çalışma, Türkiye sivil havacılık sektöründe faaliyet gösteren beş havayolu firmasının 2019-2023 dönemindeki operasyonel ve finansal etkinliklerini iki aşamalı ağ yapılı veri zarflama analizi ile değerlendirmektedir. İlk aşamada operasyonel girdilerin uçuş üretimine, ikinci aşamada operasyonel çıktıların finansal rasyolara dönüşüm etkinliği hesaplanmıştır. Shannon entropi yöntemiyle objektif ağırlıklandırma, bulanık mantık ile belirsizlik modelleme ve öteleme değişmezliği ile negatif değer dönüşümü uygulanmıştır. Bulgular, operasyonel etkinlik ortalamasının (0.886) finansal etkinlikten (0.681) yüksek olduğunu göstermiştir. Sadece yüzde 16 karar verme birimi her iki aşamada tam etkindir. COVID-19 pandemisi 2020 yılında finansal etkinlikte yüzde 65 azalmaya neden olmuş, ancak sektör 2023 yılında salgın öncesi seviyelerin üzerine çıkarak güçlü toparlanma kapasitesi göstermiştir. Friedman testi yıllar arası farkları anlamlı bulmuştur (p=0.003). Çalışma, metodolojik katkı sağlamakta ve firmalar için hedefe yönelik yönetsel öneriler sunmaktadır.

Anahtar Kelimeler

• Ağ yapılı Veri zarflama analizi
• havayolu etkinliği
• finansal performans
• COVID-19

Kaynakça

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