How explosive are cryptocurrency prices?

This paper revisits the issue of price explosiveness in cryptocurrency markets by analysing the prices of Bitcoin, XRP, Ether, and Litecoin not only expressed in US Dollars, but also the price of the latter three expressed in Bitcoin. There is strong evidence of explosive periods in cryptocurrency prices expressed in US Dollars, but also when XRP and Ether are expressed in Bitcoin. Whether or not these explosive periods can be interpreted as cryptocurrency bubbles requires a sufficient understanding of the fundamental value of cryptocurrencies. As this is currently insufficient, the term bubble should be used with more caution.