Hedge fund manager David Einhorn discussed two positions his firm has taken, both relating to leasing in the transportation industry.

The Greenlight Capital founder and president said Monday at the 24th annual Sohn Investment Conference in New York that his fund has a long position on AerBus and a short on GATX. AerCap is involved in airplane leasing, while GATX is a leader in rail cars.

Speaking favorably of both industries, he said the airline sector has some advantages over rail that make AerCap the better choice over GATX, which he thinks could be overvalued.

"Neither has consumer-facing businesses, and both have terrible news. AerCap operates in a growing industry with a favorable outlook," Einhorn said. "We think the market has it wrong."