Investors with an interest in Financial - Investment Management stocks have likely encountered both Affiliated Managers Group (AMG) and T. Rowe Price (TROW). But which of these two stocks is more attractive to value investors? We'll need to take a closer look to find out.There are plenty of strategies for discovering value stocks, but we have found that pairing a strong Zacks Rank with an impressive grade in the Value category of our Style Scores system produces the best returns. The Zacks Rank favors stocks with strong earnings estimate revision trends, and our Style Scores highlight companies with specific traits.Affiliated Managers Group and T. Rowe Price are sporting Zacks Ranks of #2 (Buy) and #4 (Sell), respectively, right now. This means that AMG's earnings estimate revision activity has been more impressive, so investors should feel comfortable with its improving analyst outlook. But this is just one factor that value investors are interested in.Value investors also tend to look at a number of traditional, tried-and-true figures to help them find stocks that they believe are undervalued at their current share price levels.Our Value category highlights undervalued companies by looking at a variety of key metrics, including the popular P/E ratio, as well as the P/S ratio, earnings yield, cash flow per share, and a variety of other fundamentals that have been used by value investors for years.AMG currently has a forward P/E ratio of 7.96, while TROW has a forward P/E of 15.82. We also note that AMG has a PEG ratio of 1. This figure is similar to the commonly-used P/E ratio, with the PEG ratio also factoring in a company's expected earnings growth rate. TROW currently has a PEG ratio of 2.26.Another notable valuation metric for AMG is its P/B ratio of 1.64. The P/B ratio pits a stock's market value against its book value, which is defined as total assets minus total liabilities. For comparison, TROW has a P/B of 3.07.Based on these metrics and many more, AMG holds a Value grade of A, while TROW has a Value grade of C.AMG is currently sporting an improving earnings outlook, which makes it stick out in our Zacks Rank model. And, based on the above valuation metrics, we feel that AMG is likely the superior value option right now. Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. It’s a little-known chemical company that’s up 65% over last year, yet still dirt cheap. With unrelenting demand, soaring 2022 earnings estimates, and $1.5 billion for repurchasing shares, retail investors could jump in at any time. This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.Free: See Our Top Stock and 4 Runners Up >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Affiliated Managers Group, Inc. (AMG): Free Stock Analysis Report T. Rowe Price Group, Inc. (TROW): Free Stock Analysis ReportTo read this article on Zacks.com click here.Zacks Investment Research