Doğrusal Olmayan Birim Kök Testleri Kullanılarak 21 OECD Ülkesinde Sağlık Harcamaları Yakınsamasının Test Edilmesi

Abstract

Amaç: Bu çalışma, 1975 ve 2019 yılları için 21 OECD ülkesinde sağlık harcamalarının stokastik zaman serisi davranışını bir dizi güncel birim kök testi kullanarak analiz etmeyi amaçlamaktadır. Gereç ve Yöntem: Bu çalışmada, 21 OECD ülkesinin sağlık harcaması verilerinin bu ülkelerin sağlık harcamaları arasında bir yakınsama olup olmadığını ampirik olarak test etmek için doğrusal ADF birim kök testi ve sekiz ilgili doğrusal olmayan birim kök testi kullanılmıştır. Bulgular: Ampirik bulgular, 21 OECD ülkesinin 20'sinde sağlık harcamalarının durağanlığını desteklemektedir. Sonuç: OECD ülkelerinin çoğunda sağlık yakınsama hipotezi doğrulanmış olup, sağlık harcamaları şoklarının ülke düzeyinde sağlık harcamaları üzerinde yalnızca geçici etkileri olduğunu göstermektedir. Bu ampirik çalışma çok önemli politika sonuçları sunmaktadır. Politika otoritelerinin alacağı politika tedbirlerinin sağlık harcamaları verisindeki olası doğrusal olmayanlığı göz ardı edilerek yapılamayacağı çalışmanın ampirik kısmında teyit edilmiştir. Sonuç kısmında sıralanan politika önerilerine alt rejim dönemlerinde daha fazla yatırım yapılması ve yüksek rejim dönemlerde ise var olanın sürdürülmesinin sağlık harcamaları yakınsaması için yeter koşul sağladığı belirlenmiştir. Bunun yanı sıra Japonya ve Güney Kore gibi ülkelerde rejimden bağımsız yapısal değişimlerin sağlık harcamaları yakınsamasında da değişim yarattığı belirlenmiştir. Bu tarz ülkelerde yapısal değişimler gözetilerek yatırımların yapılması önem arz etmektedir.

Keywords

• Sağlık harcamaları yakınsaması
• OECD ülkeleri
• Doğrusal olmayan birim kök testleri

Testing Health Expenditure Convergence In 21 OECD Countries By Using Nonlinear Unit Root Tests

Abstract

Objective: The purpose of this study is to analyze the stochastic time series behaviour of health expenditure in the 21 OECD countries between 1975 and 2019 using a variety of state-of-the-art (cutting-edge) unit root tests. Methods: In this study, the linear ADF unit root test and eight relevant nonlinear unit root tests are used to empirically estimate whether the 21 OECD countries’ health expenditure data show convergence. Results: The empirical findings are in support the stationarity of health expenditure in 20 of the 21 OECD countries. Conclusions: Health convergence hypothesis is confirmed in most OECD countries, indicating that health expenditure shocks have solely temporary effects on country-level health expenditure. The empirical study provides significant policy implications. The empirical part of the study indicated that policy measures chosen by the policymakers cannot be made without considering possible nonlinearities in health expenditure data. More investment in the policy proposals stated in the conclusion section in the low regime years, as well as the continuation of current ones in the high regime periods, have been determined to offer appropriate conditions for health spending convergence. Furthermore, it has been determined that structural changes outside of the regime have resulted in a change in health expenditure convergence in countries such as Japan and South Korea. It is essential to invest in these countries while taking into account the periods of structural change.

Keywords

• Health expenditure convergence
• OECD countries
• Nonlinear unit root tests

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