If you own shares of Advanced Micro Devices, (NASDAQ:AMD)Rambus (NASDAQ:RMBS), or athenahealth, Inc (NASDAQ:ATHN), prepare yourself for a wild ride this week.

All three of these companies are reporting earnings, and all three are heavily shorted -- with lots of investors betting against their short-term success. When these two variables combine, volatility is almost always the result.

Don't believe me? Just check out to the three stocks I called out two weeks ago: they moved an average of 12 percent following their respective earnings releases.

But instead of trying to time the market, I think it's much better for shareholders to prepare themselves for the volatility and focus on the factors that really matter to their long-term investing theses.

To help you do that, I've highlighted some important variables in the slideshow below that are worth watching for.

Sources: Finviz.com, E*Trade.

Brian Stoffel owns shares of Berkshire Hathaway. The Motley Fool recommends Athenahealth and Berkshire Hathaway. The Motley Fool owns shares of Berkshire Hathaway. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.