Why MGM Resorts International, Arch Coal, and LendingTree Slumped Today

The stock market climbed sharply on Thursday, responding well to favorable earnings results from several corners of the market. Major benchmarks were up 1% to 2%, with particularly good performance from the Nasdaq Compositethanks to the tech sector's outperformance during the day. Yet some stocks suffered from bad news that cast doubt on companies' ability to benefit from generally favorable business conditions.

MGM Resorts International (NYSE: MGM), Arch Coal (NYSE: ARCH), and LendingTree (NASDAQ: TREE)were among the worst performers on the day. Here's why they did so poorly.