Consumer-confidence numbers also have steadily risen, hitting highs not seen since early 2008. Doesn’t that mean more gifts under the nation’s Christmas trees and a jolly holiday for retailers?

Not necessarily, economists say.

The relationship between Black Friday, consumer confidence, and holiday spending is shaky—and concerns about the fiscal cliff could still mar this shopping season.

“What happens in Washington regarding the fiscal cliff has the potential to alter holiday spending, even at this late date,” said Scott Hoyt, senior director of consumer economics for Moody’s Analytics. …

But don’t take too much stock in these numbers, says Paul Ashworth, chief U.S. economist at macroeconomic research firm Capital Economics. For one, they aren’t official, government-issued numbers at the national level—they’re anecdotal. …

“If you think about this conceptually, people that spend more at Black Friday, does that mean they’ll then spend more through the rest of the holiday season, or does it mean because they spent money on Black Friday, they’ve bought all their holiday gifts and they don’t need to spend money?” Ashworth asks.