Yes / We develop bespoke rational bubble models for Bitcoin and cryptocurrencies that incorporate both heavy tails and the probability of a complete collapse in asset prices. Empirically, we present robustified evidence of bubbles in Bitcoin and Ethereum. Theoretically, we show that liquidity risks may generate heavy-tails in Bitcoin and cryptocurrency markets. Even in the absence of bubbles dramatic booms and busts can occur. We thus sound a timely note of caution.

Yes / In this paper we draw upon the close relationship between statistical physics and mathematical finance to develop a suite of models for financial bubbles and crashes. The derived models allow for a probabilistic and statistical formulation of econophysics models closely linked to mainstream financial models. Applications include monitoring the stability of financial systems and the subsequent policy implications. We emphasise the timeliness of our contribution with an application to the two largest cryptocurrency markets: Bitcoin and Ripple. Results shed new light on emerging debates over the nature of cryptocurrency markets and competition between rival digital currencies.

Yes / This paper investigates the influence that information asymmetry may possess upon the future volatility, liquidity, market toxicity and returns within cryptocurrency markets. We use the adverse selection component of the effective spread as a proxy for overall information asymmetry. Using order and trade data from the Bitfinex Exchange, we first document statistically significant adverse selection costs for major cryptocurrencies. Our results also suggest that adverse selection costs, on average, correspond to ten percent of the estimated effective spread, indicating an economically significant impact of adverse selection risk on transaction costs in cryptocurrency markets. We finally document that adverse selection costs are important predictors of intraday volatility, liquidity, market toxicity, and returns. / Türkiye Bilimler Akademisi. Grant Number: Outstanding Young Scientist. / The full-text of this article will be released for public view at the end of the publisher embargo on 11 Jan 2025.

Bitcoin is a new evolutionary development within the internet and payment system. Its price has a high volatile nature what brings a lot of attention to this cryptocurrency. This paper investigates the price formation of the Bitcoin by looking at three determinants: speculative position, transaction volume and the utility users obtain from joining the network. To see the correlation between these determinants and the influence it has on the Bitcoin price a multiple regression model has been built over the time period from 2017 to 2019.  The model shows that the effect of speculation is heavier than any other variable, reflecting the uncertainty brought by the sensible sentiment of speculators and users.

(english) This thesis deals with cybercriminality in area of cryptocurrencies. The thesis first of all describes basic terms, sources of law and issues of jurisdictions in area. Furthermore it deals with delineation of selected crimes commited in connection with cryptocurrencies. Part of the thesis focuses on issues with anonymity and proving. Key words Cybercriminality, Cryptocurrencies, Computer Criminality

The thesis focuses at the evolution of cryptocurrencies or more precisely at the competition process between them in expanding to broader usage. The first main goal of the work is to find out, whether Bitcoin, as the first and still most capitalized cryptocurrency, has an advantage of higher maturity than alternative cryptocurrencies. The second goal is to analyze whether the individual cryptocurrencies are perceived individually by market participants, which could grant the alternative cryptocurrencies an option to compete with Bitcoin by offering better features as safer technology or faster transaction. The analysis of volatility patterns in their exchange rates via various GARCH models suggests that Bitcoin still has advantage in higher maturity. The analysis of the correlation between various alternative cryptocurrencies and Bitcoin finds positive correlation and thus suggests that the cryptocurrencies are rather perceived together. JEL Classification G17, G19, E40, E41 Keywords cryptocurrencies, volatility, GARCH, money, correlation Author's e-mail 79828843@fsv.cuni.cz Supervisor's e-mail frantisek.cech@fsv.cuni.cz

The thesis explains the main characteristics and cryptocurrency definition. The thesis also offers cryptocurrency awareness analysis of Czech respondents. As part of this thesis there are also described legal and tax environments in the Czech Republic. The thesis focuses on specifics of taxation of income from cryptocurrency transactions. When the tax liability arises, it submits proposals to which category does the income belong and it comprehensively describes the procedure for calculating the tax base and subsequent taxation. In the case of legal entities, it presents the basic procedures for dealing with cryptocurrencies in the company. It deals with the „de lege ferenda“ taxation of income.

In the diploma thesis we will deal with the design of processes for managing the free capital of the company in the stock market (the results are interpreted on historical data) and the cryptocurrency market. Free cash is capitalized on both markets by using a selected investment strategy for each market and see if the investment was profitable.

This thesis deals with cryptocurrencies and the underlying principles they are based on. It describes the blockchain technology and explores various cryptocurrencies that utilize it with the focus on their similarities and differences. The next part analyzes InsightAPI, the existing tool for real-time Bitcoin blockchain exploration. It then describes the proposed solution for the Ethereum blockchain explorer, highlights the implementation details, and shows results of its testing. The created tool allows the user to quickly gather information about desired blocks, users, and transactions of the Ethereum blockchain.

The dissertation examined the effect of cryptocurrencies on the portfolio risk-adjusted returns of traditional and alternative investments using daily arithmetic returns from August 2015 to October 2018 of traditional assets (South African stocks, bonds, currencies), alternative assets (commodities, South African real estate) and cryptocurrencies (Cryptocurrency index (CRIX) and ten other individual cryptocurrencies). This is worth investigating as cryptocurrencies have been performing well while the listed equities in South Africa and most alternative investments have been underperforming (Srilakshmi & Karpagam, 2017). The mean-variance analysis, the Sharpe ratio, the conditional value-at-risk (CVaR) and the mean-variance spanning techniques were employed to analyse the data. The spanning test carried out was the multivariate ordinary least squares (OLS) regression Wald test. The research findings showed that the inclusion of cryptocurrencies in a portfolio of investments improves the efficient frontier of the portfolio of investments and the portfolio of investments risk-adjusted returns. Moreover, the findings suggested that cryptocurrencies are good portfolio diversification assets. However, investments in cryptocurrencies should be made with caution as the risks of investments are high in relation to traditional and alternative investments. The findings of this study advocate for individual and institutional investors to include cryptocurrencies within their South African portfolio of traditional and alternative investments.