Wall Street set for slightly higher open as oil steadies

U.S. stock indexes were set to open higher on Tuesday, tracking a rise in crude oil, even as Alcoa kicked off the earnings season with a lackluster quarterly report. Shares of Alcoa were down 3.2 percent at $9.43 in premarket trading. Investors will turn their attention to corporate earnings over the next several weeks, amid turbulent global markets and the uncertainty surrounding the U.S. Federal Reserve's plan to raise interest rates.