Because there is no job quite like the presidency, anyone elected to that office will have a certain amount of on-the-job training. But it’s also true that there are better and worse ways to prepare. Most Supreme Court justices arrive there after long careers of interpreting law at increasingly influential courts. CEOs of large companies have either risen through the ranks within one company or are hired in from other companies where they’ve gradually amassed relevant experience. The skill sets developed within smaller units will transfer to larger units of the same type of organization.

How does one train to be an effective president? In 2012, two political scientists, Arthur Simon and Joseph Uscinski, set out to answer that question by examining the background of every U.S. president since 1900 and compiling detailed ratings of how each performed while in office. When they analyzed predictors of success, two types of experience stood out — active military duty in a leadership role and having served as governor of a larger-than-average state.

They found that business experience did not correlate with how well someone would perform as president, and in the few areas in which there was a small correlation, they were all negative. Again, this is what we’d expect. There is nothing in a corporate hierarchy remotely similar to the separation of powers in the federal government, with the president having to deal with 535 senators and representatives in order to get anything done, nor is a modern corporation similar to the much more rigid and bureaucratic executive branch.