  We study recurrent patterns in volatility and volume for major
cryptocurrencies, Bitcoin and Ether, using data from two centralized exchanges
(Coinbase Pro and Binance) and a decentralized exchange (Uniswap V2). We find
systematic patterns in both volatility and volume across day-of-the-week,
hour-of-the-day, and within the hour. These patterns have grown stronger over
the years and can be related to algorithmic trading and funding times in
futures markets. We also document that price formation mainly takes place on
the centralized exchanges while price adjustments on the decentralized
exchanges can be sluggish.
