Investors interested in stocks from the Medical - Drugs sector have probably already heard of Jazz Pharmaceuticals (JAZZ) and Zoetis (ZTS). But which of these two stocks offers value investors a better bang for their buck right now? We'll need to take a closer look.Everyone has their own methods for finding great value opportunities, but our model includes pairing an impressive grade in the Value category of our Style Scores system with a strong Zacks Rank. The Zacks Rank is a proven strategy that targets companies with positive earnings estimate revision trends, while our Style Scores work to grade companies based on specific traits.Currently, Jazz Pharmaceuticals has a Zacks Rank of #2 (Buy), while Zoetis has a Zacks Rank of #3 (Hold). Investors should feel comfortable knowing that JAZZ likely has seen a stronger improvement to its earnings outlook than ZTS has recently. But this is only part of the picture for value investors.Value investors also try to analyze a wide range of traditional figures and metrics to help determine whether a company is undervalued at its current share price levels.The Style Score Value grade factors in a variety of key fundamental metrics, including the popular P/E ratio, P/S ratio, earnings yield, cash flow per share, and a number of other key stats that are commonly used by value investors.JAZZ currently has a forward P/E ratio of 11.54, while ZTS has a forward P/E of 45.22. We also note that JAZZ has a PEG ratio of 3.50. 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. ZTS currently has a PEG ratio of 4.68.Another notable valuation metric for JAZZ is its P/B ratio of 2.53. 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, ZTS has a P/B of 26.These are just a few of the metrics contributing to JAZZ's Value grade of B and ZTS's Value grade of C.JAZZ stands above ZTS thanks to its solid earnings outlook, and based on these valuation figures, we also feel that JAZZ is the superior value option right now.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 Jazz Pharmaceuticals PLC (JAZZ): Free Stock Analysis Report Zoetis Inc. (ZTS): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research