TY - JOUR T1 - Kripto Para Değerleri için Spekülatif Fiyat Balonlarının Test Edilmesi : Bitcoin Üzerine Bir Uygulama TT - Testing Speculative Price Bubbles For Crypto Money Values : An Application For Bitcoin Abstract AU - Hepkorucu, Atilla AU - Genç, Sevdanur PY - 2019 DA - July JF - Veri Bilimi JO - Data Sci. J. PB - Murat GÖK WT - DergiPark SN - 2667-582X SP - 44 EP - 50 VL - 2 IS - 1 LA - tr AB - Bu çalışmanın amacı;Bitcoin varlığının incelenerek, Kripto para birimleri için spekülatif fiyatşişkinliklerinin belirlenmesidir. Kripto para birimleri içinde işlem hacmi enyüksek olan varlık Bitcoin olarak belirlenmiş ve bu nedenle kripto parafiyatlarının veri üretme mekanizmasını yansıtabileceği düşünülmüştür. Tümkripto para birimlerinin değerleri yakın zamanda çok dalgalanma göstermiştir.Bu değişimin nedeni olarak spekülatif fiyat şişkinlikleri gösterilebilir. Eğerneden spekülatif fiyat artışı değil ise piyasanın sistematik riskinin arttığısonucuna varılabilir. Çalışma aralığı, Bitcoin varlığının getirivolatilitesinin arttığı dönem seçilmeye çalışılmıştır. Öncelikle durağanlığın test edilmesi amacıyla standart ArttırılmışDickey-Fuller (ADF) testikullanılmıştır. Fiyat şişkinliklerinin belirlenmesi için; dağılımlarındaaşırı sağ kuyruk yapısını dikkate alan, özyinelemeli bir yapıya sahip olan veçoklu fiyat balonlarının tespiti için geliştirilen GSADF (Phillips, Shi ve Yu; 2013) testi kullanılmıştır.Amaçlanan fiyat değişiminin nedeninin spekülatif olup olmadığınınbelirlenmesidir. KW - Bitcoin KW - Kripto Para Birimleri KW - Fiyat Balonları KW - ADF Birim Kök Testleri KW - Durağanlık N2 - The aim of this study is to determination of the speculative pricebubbles for crypto currencies by existence of bitcoin examining. The entitywith the highest transaction volume within the crypto currencies is designatedas Bitcoin, which is why it is thought that crypto money prices can reflect thedata generation process. The values of all cryptocurrencies have recently showna lot of price fluctuations. The speculative price bubbles can be shown as thecause of this change. If it is not the speculative price increase, it can bethe result of the systematic risk increase of the market. The study period wasattempted to select the period in which the volatility of Bitcoin asset returnsincrease. First, the standard Augmented Dickey-Fuller (ADF) test was used totest the stationary. In order to determine speculative price bubbles; GSADF(Phillips, Shi and Yu; 2013) test, which developed for the determination ofmultiple price bubbles in recursive way, takes into account the extreme righttail structure in the distributions. The purpose is to determine whether thecause of price change is speculative or not. CR - Wallace, B., (2011). “The Rise and Fall of Bitcoin.”, Wired Magazine, 19.12, http://www.wired.com/2011/11/mf_bitcoin/all/, Erişim Tarihi : 08.12..2018. CR - Grinberg, R., 2012. 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