As reported by IT Wire:

According to three U.S. mathematicians, if you are waiting for something, like a ride on a bus, and its late, keep on waiting rather than walk to the next bus stop.

[...]

They developed a mathematical formula that tells you how long you should wait before trying something different. They found that when both options seem reasonable, you should stay where you are and do nothing but continue waiting.

And with the exception of extreme cases:

[Even] if it is frustrating to continue waiting, you are better off doing so.

You learn something new every day, huh?