The assumption in political science has always been that electing challengers can lead to a downturn in performance. It takes time to do all the hiring involved in establishing a new government, and there is always a learning curve about processes and procedures. But a surprising new paper shows the opposite might be true. In “Electoral Turnovers”, Boston University economist Benjamin Marx uses a vast new data set to show that ousting the incumbent always seems to lead to improved performance, especially economic performance.