Cryptocurrencies provide a natural environment for checking the presence of price bubbles using the local theory of
buy cryptocurrency coins martingale bubbles, for the reason that cryptocurrencies do not distribution of cash flows. Using a reliable statistical algorithm, we check the presence of price bubbles in eight cryptocurrencies: bitcoin (btc), litecoin (ltc), ethereum (eth), ripple (xrp), bitcoin cash (bch), eos (eos), monero (xmr) and zcash (zec), starting from january 1. This issue is through july 17 next year. The statistical test first evaluates the volatility of cryptocurrencies based on the price level. Then these estimates are extrapolated to a positive real line by means of power functions. Finally, these power functions are hidden in the woven basis of a sequence of hypothesis tests for price bubbles, monitoring errors of both type i and type ii. Five of the eight currencies (btc, bch, eos, xmr, zec) show price bubbles, ltc does not,
change coins and the evidence replacing them with eth and xrp is inconclusive. The contract provides strong evidence of the prevalence of bubbles in cryptocurrencies.
