What makes a good investor? Barry Ritholtz of FusionIQ and The Big Picture blog says it’s not an MBA or a degree in economics.

“We churn out MBAs like made-in-China widgets, yet few ever become outstanding investors,” Ritholtz recently wrote in a Washington Post op-ed. “And don’t even ask about economists — the profession that missed the housing boom and bust, the Great Recession, the credit crisis and the market collapse.”

Instead, Ritholtz says, excellent investors are “savvy generalists. I can think of five fields that are hugely helpful to asset management. If you were to study these disciplines, your understanding of how markets work would greatly improve. And you would be a better investor.” The five fields:

• Historian — An understanding of stock market and economic history can give you the perspective needed to make savvy buy and sell decisions, Ritholtz says.

• Psychiatrist — Investors need to be prepared for the ups and downs of the market, Ritholtz says, and not succumb to their emotions, which often lead us astray.
• Trial Lawyer — Ritholtz says everyone from CEOs to fund managers to analysts are selling a bill of goods, so to speak. Being able to ask the right questions and determine which evidence is really valuable and which is not is critical.
• Mathematician/statistician — An understanding of complex math isn’t necessary, Ritholtz says. But you do need to be able to figure out and analyze compound interest rates, dividend yields, price/earnings ratios, and other simpler pieces of data.
• Accountant — You don’t need to be a forensic accountant, but you do need to be able to understand the basics of a company’s books and financial health, Ritholtz says.