Investors interested in stocks from the Transportation - Services sector have probably already heard of Deutsche Post AG and Grupo Aeroportuario del Centro Norte (OMAB Quick QuoteOMAB - Free Report) . But which of these two stocks presents investors with the better value opportunity right now? Let's take a closer look.

We have found that the best way to discover great value opportunities is to pair a strong Zacks Rank with a great grade in the Value category of our Style Scores system. The proven Zacks Rank puts an emphasis on earnings estimates and estimate revisions, while our Style Scores work to identify stocks with specific traits.

Deutsche Post AG and Grupo Aeroportuario del Centro Norte are both sporting a Zacks Rank of # 2 (Buy) right now. The Zacks Rank favors stocks that have recently seen positive revisions to their earnings estimates, so investors should rest assured that both of these companies have improving earnings outlooks. But this is just one factor that value investors are interested in.

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 Value category of the Style Scores system identifies undervalued companies by looking at a number of key metrics. These include the long-favored P/E ratio, P/S ratio, earnings yield, cash flow per share, and a variety of other fundamentals that help us determine a company's fair value.

DPSGY currently has a forward P/E ratio of 13.02, while OMAB has a forward P/E of 22.50. We also note that DPSGY has a PEG ratio of 0.92. 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. OMAB currently has a PEG ratio of 7.50.

Another notable valuation metric for DPSGY is its P/B ratio of 3.84. The P/B ratio is used to compare a stock's market value with its book value, which is defined as total assets minus total liabilities. For comparison, OMAB has a P/B of 4.30.

These metrics, and several others, help DPSGY earn a Value grade of A, while OMAB has been given a Value grade of D.

Both DPSGY and OMAB are impressive stocks with solid earnings outlooks, but based on these valuation figures, we feel that DPSGY is the superior value option right now.