Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Vertex Energy Inc (VTNR -7.34%) jumped as much as 14% today after an analyst reiterated a buy rating.

So what: Wunderlich Securities analyst Michael E. Hoffman kept Vertex on his buy list and raised his price target for the stock from $10 to $12 per share. He said that growth is expected to be higher than previously anticipated in 2015, and margins should be up as well, which resulted in the higher price target.  

Now what: Stocks often move on analyst upgrades or downgrades, but long-term analysts have a poor record against the market. The other thing we can count on is that results won't be the same as analyst models because analysts have been off on Vertex Energy's earnings per share estimates by an average of 101% in the last three quarters. I'd compare this note to how you view the company, but don't take any Wall Street rating as the only reason to buy or sell a stock.