One of the major perils to investing in retail stocks is the variable nature of sales patterns. A classic example of "one minute you're up and the next you're down" today was upscale retailer The Neiman Marcus Group (NYSE:NMGa).

Things appeared to be proceeding quite well after the market closed yesterday, with the company reporting better-than-expected first-quarter results. Quarterly earnings at Neiman Marcus were $1.49 per share (adjusting for a one-time disposition), which was $0.04 ahead of the analysts' consensus estimate and 28% above last year's earnings of $1.16 per share. Throw in an 11% jump in revenues and a 10.6% increase in same-store sales, and the company was primed for a brisk advance today.

It was a good thing that I didn't write this last night, because the tide turned once the monthly sales numbers hit the press. Retailers reported November sales figures this morning, and Neiman Marcus was definitely left on the short end of the lipstick.

The company's November same-store sales grew a respectable 8.4% but came in below the expected 9.8% advance. A 16.5% gain at Neiman Marcus Direct, which was bolstered by women's apparel, handbags, shoes, accessories, and linens, was tempered by a more modest 6.6% rise in Neiman Marcus and Bergdorf Goodman stores' sales.

The same-store sales results at other department store retailers for November were definitely mixed: Federated Department Stores (NYSE:FD) dropped 1.4%, and May Department Stores declined 7.7%; on the positive side, J.C. Penney (NYSE:JCP) was up 12%, and Nordstrom (NYSE:JWN) grew 3.1%. The general consensus among retailers was that "Black Friday" store traffic (the day after Thanksgiving) was a bit slow. I'm just wondering whether that was after people stampeded while I was still sleeping to get those early-morning bargains.

While Neiman did come up short of its same-store sales forecast in November, its first quarter (of its fiscal 2005) results were commendable. The company's "emphasis on full-price selling and disciplined inventory management" continues to drive positive quarterly results.

Because of the uncertainty of the retail environment and the fact that Neiman's shares are trading at 15 times this year's earnings estimate of $4.59 per share (versus a 14% growth rate), I see the shares as fairly valued at this time (when you throw in the company's 0.76% dividend yield).

You don't have to up before the crack of dawn to shop for these other views:

Fool contributor Phil Wohl spent more than 12 years on Wall Street and does not own shares in any of the company's mentioned above.