The Efficient Market Hypothesis is one of the most popular subjects in the empirical finance literature. Previous studies in the stock markets, which are mostly based on fixed time price variations, do not provide conclusive findings, in which evidence of short-term predictability varies...

We find the well-documented U-shaped intraday patterns of stock liquidity, volume, and price volatility for the U.S. stock market have disappeared. Bid-ask spreads tend to decrease, not increase, toward the close of the trading day; trading volume disproportionally concentrates in the last five...