Testing Speculative Price Bubbles For Crypto Money Values : An Application For Bitcoin Abstract

Öz

The aim of this study is to determination of the speculative price bubbles for crypto currencies by existence of bitcoin examining. The entity with the highest transaction volume within the crypto currencies is designated as Bitcoin, which is why it is thought that crypto money prices can reflect the data generation process. The values of all cryptocurrencies have recently shown a lot of price fluctuations. The speculative price bubbles can be shown as the cause of this change. If it is not the speculative price increase, it can be the result of the systematic risk increase of the market. The study period was attempted to select the period in which the volatility of Bitcoin asset returns increase. First, the standard Augmented Dickey-Fuller (ADF) test was used to test the stationary. In order to determine speculative price bubbles; GSADF (Phillips, Shi and Yu; 2013) test, which developed for the determination of multiple price bubbles in recursive way, takes into account the extreme right tail structure in the distributions. The purpose is to determine whether the cause of price change is speculative or not. 

Anahtar Kelimeler

• Bitcoin,Crypto Money Values,Price Bubbles,ADF Unit Root Tests,Stationary

Kripto Para Değerleri için Spekülatif Fiyat Balonlarının Test Edilmesi : Bitcoin Üzerine Bir Uygulama

Öz

Bu çalışmanın amacı; Bitcoin varlığının incelenerek, Kripto para birimleri için spekülatif fiyat şişkinliklerinin belirlenmesidir. Kripto para birimleri içinde işlem hacmi en yüksek olan varlık Bitcoin olarak belirlenmiş ve bu nedenle kripto para fiyatlarının veri üretme mekanizmasını yansıtabileceği düşünülmüştür. Tüm kripto para birimlerinin değerleri yakın zamanda çok dalgalanma göstermiştir. Bu değişimin nedeni olarak spekülatif fiyat şişkinlikleri gösterilebilir. Eğer neden spekülatif fiyat artışı değil ise piyasanın sistematik riskinin arttığı sonucuna varılabilir. Çalışma aralığı, Bitcoin varlığının getiri volatilitesinin arttığı dönem seçilmeye çalışılmıştır. Öncelikle durağanlığın test edilmesi amacıyla standart Arttırılmış Dickey-Fuller (ADF) testi kullanılmıştır. Fiyat şişkinliklerinin belirlenmesi için; dağılımlarında aşırı sağ kuyruk yapısını dikkate alan, özyinelemeli bir yapıya sahip olan ve çoklu fiyat balonlarının tespiti için geliştirilen GSADF (Phillips, Shi ve Yu; 2013) testi kullanılmıştır. Amaçlanan fiyat değişiminin nedeninin spekülatif olup olmadığının belirlenmesidir.

Anahtar Kelimeler

• Bitcoin,Kripto Para Birimleri,Fiyat Balonları,ADF Birim Kök Testleri,Durağanlık

Kaynakça

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