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What: Shares of discount retailer Big Lots (NYSE: BIG) fell as much as 10% on Friday after its quarterly results and outlook disappointed Wall Street.

So what: Big Lots' stock has rallied over the past few months, but the third-quarter earnings miss -- $0.06 per share versus the consensus of $0.09 per share -- suggests that things aren't as rosy as Wall Street thinks. While the company has been able to lure customers away from larger rivals like Wal-Mart (NYSE: WMT) and Costco (Nasdaq: COST) with big discounts, sliding gross margins are triggering concerns over its long-term profitability.

Now what: Looking ahead, Big Lots cautiously sees full-year EPS of $2.85-$2.92, while analysts are expecting about $2.89. "The question we don't know the answer to is which trend will carry forward throughout the Christmas season -- the more cautious consumer of early November, or will the robust traffic pattern of Thanksgiving weekend dominate in December?" said CEO Steven Fishman. While the short term is anyone's guess, long-term investors are probably safer in the stalwarts mentioned above.

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