Investors with an interest in Financial Transaction Services stocks have likely encountered both Fidelity National Information Services (FIS Quick QuoteFIS - Free Report) and MasterCard (MA Quick QuoteMA - Free Report) . 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 proven Zacks Rank puts an emphasis on earnings estimates and estimate revisions, while our Style Scores work to identify stocks with specific traits.

Fidelity National Information Services has a Zacks Rank of #2 (Buy), while MasterCard has a Zacks Rank of #3 (Hold) right now. Investors should feel comfortable knowing that FIS likely has seen a stronger improvement to its earnings outlook than MA has recently. But this is just one factor that value investors are interested in.

Value investors analyze a variety of traditional, tried-and-true metrics to help find companies 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.

FIS currently has a forward P/E ratio of 9.95, while MA has a forward P/E of 32.79. We also note that FIS has a PEG ratio of 0.94. This metric is used similarly to the famous P/E ratio, but the PEG ratio also takes into account the stock's expected earnings growth rate. MA currently has a PEG ratio of 1.87.

Another notable valuation metric for FIS is its P/B ratio of 1.29. Investors use the P/B ratio to look at a stock's market value versus its book value, which is defined as total assets minus total liabilities. By comparison, MA has a P/B of 70.51.

Based on these metrics and many more, FIS holds a Value grade of B, while MA has a Value grade of D.

FIS sticks out from MA in both our Zacks Rank and Style Scores models, so value investors will likely feel that FIS is the better option right now.