Greetings, Fools. It's once again time to divine -- with quite a degree of accuracy -- which stocks will be making big moves on Wall Street in the week ahead. Last time I made such a prediction, the average stock moved 19% on the date I predicted. This week, I believe that shares of on-line car-buying specialist TrueCar (NASDAQ:TRUE), retailer Nordstrom (NYSE:JWN), and Sam Adams' parent Boston Beer (NYSE:SAM) will be the big movers.

Why do I think this? Because all three of these companies are heavily shorted --or have investors betting against them -- and all three are reporting earnings. When these two forces combine, volatility is almost always the result.

But I don't suggest trying to make a quick fortune based on this information. You can just as easily lose a quick fortune. Instead, I think current shareholders need to be prepared for the volatility, and be able to differentiate between noise, and an actual signal in the week ahead. That's what's included in the slideshow below.

Photos: TrueCar, Nicholas Eckhart--via Flickr, Boston Beer.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.