Investors often turn to recommendations made by Wall Street analysts before making a Buy, Sell, or Hold decision about a stock. While media reports about rating changes by these brokerage-firm employed (or sellside) analysts often affect a stock's price, do they really matter? Before we discuss the reliability of brokerage recommendations and how to use them to your advantage, let's see what these Wall Street heavyweights think about Petrobras (PBR) . Petrobras currently has an average brokerage recommendat ...