Why Traders Make Markets Inefficient The Efficient-Market Hypothesis (EMH) is a popular theory within the world of finance. The idea behind EMH is that the stock market is "informationally efficient," meaning that a stock is always accurately valued at any given time based on the information that is publicly available about that stock. (3:21pm ET) A Warning Sign For Other Advertisers? Snapchat Analysts React To Shocking Guidance Cut, Stock Sell-Off Snap Inc (NYSE: SNAP) shares are plummeting 40% after CEO Evan Spiegel warned employees the company will miss its targets for revenue and earnings in the second quarter. (12:53pm ET) As Apple Continues In This Trend, Here's How To Play It Bull And Bear Apple Inc (NASDAQ: AAPL) opened lower on Tuesday after spiking up 3.86% on Monday in a relief bounce that led the S&P 500 to 1.39% higher. (11:38am ET) BZ Chart Of The Day: Is AT&T About To Break Out? Shares of AT&T Inc. (NYSE: T) have...