BANKACILIK SEKTÖRÜ HİSSE SENEDİ PİYASASININ ETKİNLİĞİ: YAPISAL KIRILMA VE GÜÇLÜ HAFIZA

Öz

Bu çalışmada 2001 kriz sonrası dönem olan 2003-2007 yılları arasında Türk bankacılık sektörünün zayıf formda etkinliği yapısal kırılma testleri ve güçlü hafıza modelleri ile araştırılmıştır. Yapısal kırılmayı göz önünde bulundurmadan elde edilen sonuçlar bankacılık sektöründe zayıf formda etkinliğin varlığına işaret etmektedir. Bunun yanı sıra, hisse fiyat serilerinin tümünde yapısal kırılma tespit edilmiş ve kırılmanın etkisi ortadan kaldırıldığında fiyat serilerinin güçlü hafıza özelliği gösterdiği ve uzun dönemde ortalamasına geri döndüğü tespit edilmiştir. Bu sonuç bankacılık sektörünün zayıf formda etkin olmadığını göstermektedir.

Anahtar Kelimeler

• Etkin Piyasa Hipotezi, Bankacılık Sektörü, Yapısal Kırılma, Güçlü Hafıza

EFFICIENCY OF BANKING SECTOR STOCK MARKET: STRUCTURAL BREAK AND LONG MEMORY

Öz

This study provides empirical evidence on weak form efficiency of the stock market in the banking sector after 2001 economic crisis in Turkey over a period of 1990-2007. It has been investigated with structural break test and long memory models. The results obtained ignoring the structural breaks point out that there exist a weak form efficiency in the stock market. Besides, it has been determined structural break effect in all stock prices series. It has been concluded that the stock prices series is mean reverting long memory process after removing the structural break effect. This result indicates that banking sector is not weak form efficient

Anahtar Kelimeler

• Efficient Market Hypothesis , Banking Sector , Structural Breaks , Long Memory

Kaynakça

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