Journals / İstatistikçiler Dergisi:İstatistik ve Aktüerya / 2026 / Cilt: 19 Sayı: 2026

Time series modeling of mortality shocks in Turkey: A Lee–Carter and ARFIMA approach

Türkiye ölümlülük şoklarının zaman serisi yaklaşımları ile modellenmesi: Lee–Carter ve ARFIMA yaklaşımı

Pages
37–49
Publication Date
2026-06-06
DOI
—
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Owing to the flexibility provided by the ARFIMA framework, the results indicate that pandemic-based mortality shocks are not merely temporary fluctuations but they may exhibit long-lasting effects over certain periods.

📌 3 Key Takeaways

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Objective & Hypothesis:In this study, mortality dynamics in Turkey are examined using population data by age and gender covering the period 2009–2023, with particular emphasis on the effects of catastrophic events such as the COVID-19 pandemic on mortality rates.
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Key Findings & Data:Within this framework, the historical development of mortality models is reviewed, and the Lee-Carter model is adopted as the core methodology due to its ability to jointly capture age-specific mortality patterns and time-varying dynamics.
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Conclusion & Impact:Owing to the flexibility provided by the ARFIMA framework, the results indicate that pandemic-based mortality shocks are not merely temporary fluctuations but they may exhibit long-lasting effects over certain periods.
🔬Design:Review & Systematic Survey
📍Scope:2009–2023 Verileri
⚙️Variables:Ölümlülük modellemesi · Lee-Carter modeli · ARFIMA

Abstract

In this study, mortality dynamics in Turkey are examined using population data by age and gender covering the period 2009–2023, with particular emphasis on the effects of catastrophic events such as the COVID-19 pandemic on mortality rates. Within this framework, the historical development of mortality models is reviewed, and the Lee-Carter model is adopted as the core methodology due to its ability to jointly capture age-specific mortality patterns and time-varying dynamics. Future projections of the time index of the Lee-Carter model are obtained using ARIMA and ARFIMA models, which are capable of capturing long-memory properties in the data. Owing to the flexibility provided by the ARFIMA framework, the results indicate that pandemic-based mortality shocks are not merely temporary fluctuations but they may exhibit long-lasting effects over certain periods. Overall, the findings demonstrate that long-memory time series approaches offer a significant advantage in modeling catastrophic mortality risk, enhancing the reliability of mortality projections and, consequently, improving the accuracy of actuarial pricing and reserve calculations.

Özet

Bu çalışmada, Türkiye’ye ait 2009–2023 dönemini kapsayan yaşa ve cinsiyete göre nüfus verileri kullanılarak ölümlülük dinamikleri incelenmiş ve özellikle COVID-19 pandemisi gibi katastrofik olayların ölümlülük oranları üzerindeki etkileri analiz edilmiştir. Ölümlülük modellerinin tarihsel gelişimi değerlendirilmiş ve yaşa bağlı ölüm yapısını zamana bağlı değişimlerle birlikte ele alabilen Lee-Carter modeli temel çerçeve olarak benimsenmiştir. Lee-Carter modelinin zaman endeksi serisinin geleceğe yönelik projeksiyonları, ARIMA ve özellikle uzun bellek özelliklerini yakalayabilen ARFIMA modelleri aracılığıyla gerçekleştirilmiştir. ARFIMA modelinin sağladığı esneklik sayesinde, pandemi kaynaklı ölümlülük şoklarının ölümlülük endeksi üzerinde yalnızca geçici dalgalanmalar değil, belirli dönemlerde daha uzun süreli etkiler yaratabileceği görülmüştür. Elde edilen sonuçlar, katastrofik ölümlülük riskinin modellenmesinde uzun bellekli zaman serisi yaklaşımlarının önemli bir üstünlük sağladığını ve bu yaklaşımların ölümlülük projeksiyonlarının güvenilirliğini, dolayısıyla fiyatlandırma ve rezerv hesaplamalarının doğruluğunu artırdığını göstermektedir.

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Cite This Article

Taşbaş, B., Özen, S. (2026). Time series modeling of mortality shocks in Turkey: A Lee–Carter and ARFIMA approach. İstatistikçiler Dergisi:İstatistik ve Aktüerya, Cilt: 19 Sayı: 2026, 37–49. https://ajindex.com/articles/1502704

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