The proven Zacks Rank system focuses on earnings estimates and estimate revisions to find winning stocks. Nevertheless, we know that our readers all have their own perspectives, so we are always looking at the latest trends in value, growth, and momentum to find strong picks.

Of these, perhaps no stock market trend is more popular than value investing, which is a strategy that has proven to be successful in all sorts of market environments. Value investors use a variety of methods, including tried-and-true valuation metrics, to find these stocks.

Zacks has developed the innovative Style Scores system to highlight stocks with specific traits. For example, value investors will be interested in stocks with great grades in the "Value" category. When paired with a high Zacks Rank, "A" grades in the Value category are among the strongest value stocks on the market today.

One company to watch right now is Selective Insurance Group (SIGI Quick QuoteSIGI - Free Report) . SIGI is currently sporting a Zacks Rank #2 (Buy), as well as an A grade for Value. The stock holds a P/E ratio of 9.89, while its industry has an average P/E of 29.62. Over the past 52 weeks, SIGI's Forward P/E has been as high as 25.81 and as low as 9.60, with a median of 11.46.

Value investors also love the P/S ratio, which is calculated by simply dividing a stock's price with the company's sales. This is a popular metric because sales are harder to manipulate on an income statement, so they are often considered a better performance indicator. SIGI has a P/S ratio of 1.09. This compares to its industry's average P/S of 1.47.

These are only a few of the key metrics included in Selective Insurance Group's strong Value grade, but they help show that the stock is likely undervalued right now. When factoring in the strength of its earnings outlook, SIGI looks like an impressive value stock at the moment.