It's not than just an sales or earnings beat. It's that, a company's potential, their industry, timing of beats, whether it not there are continuous beats, how much the stock has already moved, are the beats showing weakness (slowing down rate of increase from prior beats), etc. The only way to study this is one stock at a time over a long period and then to look at the odds. As William O'Neal, Kris Katcher, Mark Minervini, and countless others have shown time and time again, earning aren't everything but they are a criteria that indicate which pool of stocks to consider in your pool of 10,000 choices. Their results speak for themselves and their criteria which includes earnings and sales.