Bubbles in Bitcoin Markets: Gezeralized Sup ADF Test

Abstract

Along with the rapid developments in the use of internet, the money that is physically involved in human life has also started to be digitalized. Such digitized currencies are generally called crypto currencies. Currently, Bitcoin has the highest transaction volume among the crypto currencies. The first bitcoin was released in 2009. However, in the last few years it has started to attract considerable attention. One of the main reasons for this interest is the significant increase in the value of Bitcoin. In the context of these increases, it is important to investigate the existence of speculative bubbles in the Bitcoin market. In this context, the aim of this study is to investigate the presence of speculative bubbles in the Bitcoin market during the period 2015-2018. In line with the purpose, Generalized Sup ADF test developed by Phillips et al. (2015) is used to detect speculative bubbles. The results show that there are many bubbles in the bitcoin market.

Keywords

• Bitcoin,Speculative Bubbles,GSADF Test

Bitcoin Piyasasında Balonlar: Genelleştirilmiş Eküs ADF Testi

Öz

İnternet kullanımındaki hızlı gelişmeler ile birlikte, insan hayatına fiziksel olarak dahil olan para da dijitalleşmeye başlamıştır. Bu tür dijitalleşmiş para birimlerine genel olarak kripto para denilmektedir. Hali hazırda, Bitcoin, kripto para birimleri arasında en yüksek işlem hacmine sahiptir. İlk Bitcoin 2009 yılında piyasaya sürüldü. Fakat son birkaç yılda ciddi derecede ilgi çekmeye başladı. Bu ilginin temel nedenlerinden birisi, Bitcoin'in değerinde önemli artışların olmasıdır. Söz konusu değer artışları bağlamında, Bitcoin piyasasında spekülatif balonların varlığının araştırılması önem arz etmektedir. Bu bağlamda, çalışmanın amacı 2015-2018 dönemi boyunca Bitcoin piyasasında spekülatif balonların varlığını araştırmaktır. Amaç doğrultusunda, spekülatif balonların tespiti için Phillips vd. (2015) tarafından geliştirilen Genelleştirilmiş Eküs ADF testi kullanılmıştır. Elde edilen bulgular, Bitcoin piyasasında çok sayıda baloncuk olduğunu göstermektedir. 

Anahtar Kelimeler

• Bitcoin,Spekülatif Balonlar,GSADF Testi

Kaynakça

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