I show that the prices of the internationally traded crypto-currency bitcoin can be used to estimate a currency's unofficial exchange rate and capital controls at a daily interval. Two important bitcoin features are documented: (1) Bitcoin-based exchange rates approximate the behavior, but not the level, of unofficial exchange rates, and (2) Bitcoin prices contain a bitcoin-trend term and must be appropriately normalized prior to being used for this purpose. Bitcoin-based exchange rates reveal that (3) there is no consistent pattern of Granger causality between unofficial rates and official rates by exchange rate regime or barriers at the daily frequency, and (4) that countries can engage in short-interval capital controls.
Tema ovog rada su kriptovalute. Budući da većina ljudi nije pravodobno upoznata s ovom temom, ovaj rad prikazuje i opisuje kriptovalute te način na koji se upotrjebljuju u svakodnevnom životu. Kriptovalute (eng. cryptocurrency) digitalne su valute dizajnirane kao sredstvo razmjene. Poznate su po tome što su državne agencije i banke isključene iz procesa razmjene. Kriptovalute omogućuju jednostavnu, jeftinu i brzu transakciju na području cijeloga svijeta. Trenutno najisplativije kriptovalute su Bitcoin i Ethereum, a u radu je opisana njihova korisnost, prednosti i mane. Budući da se Bitcoinu predviđa uspješna budućnost i sve je prisutniji i prihvatljiviji na tržištu, u radu su navedeni primjeri iz Hrvatske koji to potvrđuju. Sve veći broj poduzetnika odlučuje se za uvođenje kriptovaluta. U primjerima je obuhvaćen širok spektar djelatnosti, od frizerskih usluga, preko raznih tvrtki koji se bave prodajom računalne opreme, ugostiteljskih usluga preko mogućnosti brzog i lakog podizana gotovine na kripto bankomatima pa sve do plaćanja komunalnih usluga, pa čak i humanitarno djelovanje. Mnogi smatraju da su kriptovalute samo sinonim za prijevare i pranje novca, no programeri tvrde da su kriptovalute samo jedna vrsta tehnologije, alat koji sam po sebi ne može biti ni dobar ni loš, ovisno o tome za što se koristi. Autor ovoga rada proveo je istraživanje o tome kako se može besplatno započeti trgovanje kriptovalutama te je anketom ispitao stavove ispitanika o implementaciji kriptovaluta u društvu.
Cryptocurrencies became popular with the emergence of Bitcoin and have shown an unprecedented growth over the last few years. As of November 2016, more than 720 cryptocurrencies exist, with Bitcoin still being the most popular one. We provide both a statistical analysis as well as an extreme value analysis of the returns of the most important cryptocurrencies. A particular focus is on the tail risk characteristics and we will provide an in-depth univariate and multivariate extreme value analysis. The tail dependence of cryptocurrencies is investigated (using both empirical and Gaussian copulas). For investors—especially institutional ones—as well as regulators, an understanding of the risk and tail characteristics are of utmost importance. For cryptocurrencies to become a mainstream investable asset class, studying these properties is necessary. Our findings show that cryptocurrencies exhibit strong non-normal characteristics, large tail dependencies, depending on the particular cryptocurrencies and heavy tails. Statistical similarities can be observed for cryptocurrencies that share the same underlying technology. This has implications for risk management, financial engineering (such as derivatives on cryptocurrencies)—both from an investor’s as well as from a regulator’s point of view. To our knowledge, this is the first detailed study looking at the extreme value behaviour of cryptocurrencies, their correlations and tail dependencies as well as their statistical properties.
We document systematic differences in bitcoin prices across 11 different markets representing 26% of global bitcoin trade volume. These differences must -due to the identical nature of all bitcoin -result from characteristics of markets themselves. We examine differences across the markets and find that those which do not require customer identification for establishing an account are more likely to deviate from representative market prices than those which do. This implies that standard financial regulations, specifically know-your-customer regulations, can have a non-negligible impact on the bitcoin market.
More and more companies start offering digital payment systems. Smartphones evolve to a digital wallet such that it seems like we are about to enter the era of digital finance. In fact we are already inside an digital economy. The market of e-x (x = "finance", "money", "book", you name it . . . ) has not only picked up enormous momentum but has become standard for driving innovative activities of the global economy. A few clicks at y and payment at z brings our purchase to location w. Own currencies for the digital market were therefore just a matter of time. The idea of the Nobel Laureate Hayek, see [1], to let companies offer concurrent currencies seemed for a long time scarcely probabilistic, but the invention of the Blockchain made it possible to fill his vision with life. Cryptocurrencies (abbr. cryptos) came up and widened the angle towards this new level of economic interaction. Since bitcoins’ appearance a bunch of new cryptos spread the web and offered new ways of proliferation. The crypto market then fanned out and showed clear signs of acceptance and deep liquidity so that one has to look closer at the general moves and dynamics.
This paper sets out to explore the hedging capabilities of bitcoin by applying the asymmetric GARCH methodology used in investigation of gold. The results show that bitcoin can clearly be used as a hedge against stocks in the Financial Times Stock Exchange Index. Additionally bitcoin can be used as a hedge against the American dollar in the short-term. Bitcoin thereby possess some of the same hedging abilities as gold and can be included in the variety of tools available to market analysts to hedge market specific risk.
This paper explores the financial asset capabilities of bitcoin using GARCH models. The initial model showed several similarities to gold and the dollar indicating hedging capabilities and advantages as a medium of exchange. The asymmetric GARCH showed that bitcoin may be useful in risk management and ideal for risk averse investors in anticipation of negative shocks to the market. Overall bitcoin has a place on the financial markets and in portfolio management as it can be classified as something in between gold and the American dollar on a scale from pure medium of exchange advantages to pure store of value advantages.
The present study addresses one of the most problematic phenomena: Bitcoin price. We explore the Granger causality for two relationships (Bitcoin price and trade transactions; Bitcoin price and investors' attractiveness) from a frequency domain perspective-based on unconditional and conditional data analysis. Accurately, this research empirically assesses the causal links between these variables unconditionally on the one hand and conditioning upon relevant control variables (recorded in literature) on the other hand. The observed outcomes reveal some differences with respect to the frequencies involved, highlighting the difficulty to reach clearer insights and better paths into this nascent crypto-currency. Beyond the nuances of short-, medium- and long-run frequencies, this paper confirms the extremely speculative nature of Bitcoin without overlooking its usefulness in economic reasons. The consideration of the Chinese market index, the hash rate, the monetary velocity and the estimated output volume has led to solid and meaningful findings connecting further Bitcoin to speculation.
To the mass public, Bitcoin is well known since its creation by its extreme volatility. However, Bitcoin’s declining fluctuations since the start 2015 has revived our attention to assess whether there is a coming Bitcoin market phase. Using an optimal GARCH model on daily data, we show that the volatility of Bitcoin price decreases notably when comparing the periods [December 2010-June 2015] and [January 2015-June 2015]. During the first interval, the Threshold- GARCH estimates reveal that there is a great duration of persistence and thus tends to follow a long memory process. For the second period, the chosen specification (Exponential-GARCH) displays less volatility persistence. Despite this remarkable volatility’s decrease, we cannot argue that Bitcoin market is mature, since the degree of asymmetry remains strong; Specifically, Bitcoin is likely to be driven by negative rather than positive shocks.
Bitcoin (BTC) is a major virtual currency. Using weekly data over the 2010-2013 period, we analyze a BTC investment from the standpoint of a US investor with a diversified portfolio including both traditional assets (worldwide stocks, bonds, hard currencies) and alternative investments (commodities, hedge funds, real estate). Over the period under consideration, BTC investment had highly distinctive features, including exceptionally high average return and volatility. Its correlation with other assets was remarkably low. Spanning tests confirm that BTC investment offers significant diversification benefits. We show that the inclusion of even a small proportion of BTCs may dramatically improve the risk-return trade-off of well-diversified portfolios. Results should however be taken with caution as the data may reflect early-stage behavior that may not last in the medium or long run.
Ifigeneia Georgoula, Demitrios E. Pournarakis, Christos Bilanakos, Dionisios N. Sotiropoulos · 5 authors
This paper uses time-series analysis to study the relationship between Bitcoin prices and fundamental economic variables, technological factors and measurements of collective mood derived from Twitter feeds. Sentiment analysis has been performed on a daily basis through the utilization of a state-of-the-art machine learning algorithm, namely Support Vector Machines (SVMs). A series of short-run regressions shows that the Twitter sentiment ratio is positively correlated with Bitcoin prices. The short-run analysis also reveals that the number of Wikipedia search queries (showing the degree of public interest in Bitcoins) and the hash rate (measuring the mining difficulty) have a positive effect on the price of Bitcoins. On the contrary, the value of Bitcoins is negatively affected by the exchange rate between the USD and the euro (which represents the general level of prices). A vector error-correction model is used to investigate the existence of long-term relationships between cointegrated variables. This kind of long-run analysis reveals that the Bitcoin price is positively associated with the number of Bitcoins in circulation (representing the total stock of money supply) and negatively associated with the Standard and Poor's 500 stock market index (which indicates the general state of the global economy).
Bitcoin has two major roles: as currency and as financial asset. This paper attempts to address these roles: whether Bitcoin is a real currency, and what its financial features are. Using daily data of the exchange rates quoted from the world major Bitcoin dealer since the inception of Bitcoin and the spot market exchange rates, we calculate the triangle arbitrage asset price to decompose the features of this currency. The results suggest significant liquidity discount of Bitcoin and risk premium as a financial asset in terms of British Pound Sterling (2.46%) and Chinese Yuan (0.3%). There is idiosyncratic risk component associated with Bitcoin implied by the Granger causality tests. Bitcoin, as investment objectives instead of currency unit, is associated with excess risk and low returns. Such poor performance discourages investors to spend Bitcoin as currency and to pursue the arbitrage profit. Investors store and hold Bitcoin as fixed asset. In addition, both arbitrage stickiness and low Treynor ratio are persistent over time.
The present paper seeks to effectively address the following question: What Bitcoin looks like? To do so, we regress Bitcoin price on a number of variables (Bitcoin fundamentals recorded in the literature) by applying an ARDL Bounds Testing approach for daily data covering the period from December 2010 to June 2014. Our findings highlight the speculative nature of Bitcoin. We also provide insightful evidence that Bitcoin may be used for economic reasons but there is any sign of being a safe haven. By considering the Chinese trading bankruptcy and the closing of Road Silk by FBI, the contribution of users’ interest stills sharply dominant, indicating the robustness of our results.
The Bitcoin has emerged as a fascinating phenomenon in the Financial markets. Without any central authority issuing the currency, the Bitcoin has been associated with controversy ever since its popularity, accompanied by increased public interest, reached high levels. Here, we contribute to the discussion by examining the potential drivers of Bitcoin prices, ranging from fundamental sources to speculative and technical ones, and we further study the potential influence of the Chinese market. The evolution of relationships is examined in both time and frequency domains utilizing the continuous wavelets framework, so that we not only comment on the development of the interconnections in time but also distinguish between short-term and long-term connections. We find that the Bitcoin forms a unique asset possessing properties of both a standard financial asset and a speculative one.
Alloreactivity after transplantation is associated with profound immune suppression, and consequent opportunistic infection results in high morbidity and mortality. This immune suppression is most profound during GVHD after bone marrow transplantation where an inflammatory cytokine storm dominates. Contrary to current dogma, which avers that this is a T-cell defect, we demonstrate that the impairment lies within conventional dendritic cells (cDCs). Significantly, exogenous antigens can only be presented by the CD8(-) cDC subset after bone marrow transplantation, and inflammation during GVHD specifically renders the MHC class II presentation pathway in this population incompetent. In contrast, both classic and cross-presentation within MHC class I remain largely intact. Importantly, this defect in antigen processing can be partially reversed by TNF inhibition or the adoptive transfer of donor cDCs generated in the absence of inflammation.