The inventor of automated trading, Thomas Peterffy, wants to scale back on high speed trading. He says it makes volatile markets worse, because high speed traders can jump in and out of the market at will, while firms like Interactive, the one he owns, are required to trade all day and stay in. “Mr. Peterffy has a solution: Require exchanges to hold orders for one-tenth of a second, while allowing registered market makers, such as Interactive, to trade at will.”