Yapay Zekâ, Dijital Finans ve Yeşil Tahvil Piyasası İlişkisi: Volatilite Yayılım Etkileri

Öz

Çalışma, 15 Haziran 2018–17 Nisan 2025 döneminde yapay zeka, FinTech ve yeşil tahvil endeksleri arasındaki volatilite dinamiklerini ve yayılma etkilerini ARCH/GARCH tipi koşullu heteroskedastisite modelleri, CCC-GARCH, QDCC-GARCH ve QFCON yaklaşımlarıyla incelemektedir. Bulgular, FinTech endeksi için en uygun modelin EGARCH(1,1), yapay zeka ve yeşil tahvil endeksleri için ise TGARCH(1,1) olduğunu göstermektedir. Pandemi döneminde tüm endekslerde belirgin volatilite kümelenmesi gözlemlenmiştir. FinTech şokları daha kalıcı ve asimetriktir. Yapay zeka piyasası ise en yüksek şok kalıcılığına sahiptir. CCC-TGARCH sonuçları, FinTech ile yapay zeka arasında çift yönlü volatilite yayılımı olduğunu, yeşil tahvillerin ise daha zayıf yayılım davranışı sergilediğini ortaya koymaktadır. QDCC-GARCH bulguları, koşullu korelasyonların zaman ve kantillere göre değiştiğini ve en güçlü bağlantının yapay zeka ile FinTech arasında olduğunu göstermektedir. QFCON sonuçları ise FinTech’in net şok yayıcı, yeşil tahvillerin ise çoğunlukla şok alıcı olduğunu doğrulamaktadır.

Anahtar Kelimeler

• Fintek
• yapay zekâ
• yeşil tahvil
• volatilite yayılımı

Artificial Intelligence, Digital Finance, and the Green Bond Market Nexus: Volatility Spillover Effects

Öz

The study examines the volatility dynamics and spillover effects among artificial intelligence, FinTech, and green bond indices during the period from June 15, 2018, to April 17, 2025, using ARCH/GARCH-type conditional heteroskedasticity models, as well as the CCC-GARCH, QDCC-GARCH, and QFCON approaches. The findings indicate that the most appropriate model for the FinTech index is EGARCH(1,1), while TGARCH(1,1) is the most suitable for the artificial intelligence and green bond indices. Significant volatility clustering was observed in all indices during the pandemic period. FinTech shocks are more persistent and asymmetric. The artificial intelligence market, however, exhibits the highest shock persistence. CCC-TGARCH results reveal a bidirectional volatility spillover between FinTech and artificial intelligence, while green bonds exhibit weaker spillover behavior. QDCC-GARCH findings show that conditional correlations vary by time and quantiles, with the strongest link observed between artificial intelligence and FinTech. QFCON results confirm that FinTech acts as a net shock transmitter, while green bonds are predominantly shock absorbers.

Anahtar Kelimeler

• Fintech
• artificial intelligence
• green bond
• volatility spillover

Kaynakça

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