NEW YORK (AP) — Electronics sellers and online merchants thrived in November, particularly the start of the holiday shopping season, but clothing and luxury merchants struggled, according to estimates to be released today.

Those results, combined with a trimmed sales prediction for retailers' official November results, raise worries that some sectors could face tough going in the critical countdown to Christmas as they grapple with frugal Americans contending with job insecurity and tight credit.

"Last year, it was uncertainty that was driving the cautiousness," said Mary Delk, director of Deloitte Consulting. This year, it's "anxiety about their (own) personal finances" that's making shoppers more frugal.

Fat discounts drove shoppers to stores and online this past weekend, and Delk thinks it's likely they won't come back until the season's final hours when the bargains are even better.

The International Council of Shopping Centres trimmed its November sales growth forecast yesterday, citing more shoppers who are saying they're putting off holiday shopping compared with a year ago.

Marshal Cohen, chief industry analyst at market research firm NPD Group, says that what's comforting is that shoppers, who had slashed their spending all year, bought plenty of items for themselves this past weekend. That means there's plenty of gift buying to go, he said.

Analysts are carefully studying how consumers behave during the holidays and beyond to get a sense of how strongly the economy will rebound from the worst recession since the 1930s. That's because spending on goods and services for consumers accounts for about 70 percent of US economic activity by federal measures. The holiday season accounts for as much as 40 percent of annual sales and profits for many retailers.

There are some encouraging signs that shoppers are just a bit more open to discretionary purchases. The battered jewellery sector rose 4.6 percent percent in November, according to MasterCard Advisors' SpendingPulse sales figures being released on Wednesday.

Overall, according to SpendingPulse, which estimates sales in all payment forms including cash and cheques, November sales proved to be "a mixed bag", said Kamalesh Rao, director of Economic Research.

Both apparel and luxury excluding jewellery weakened in November after showing signs of life in the fall. Sales for mall-based apparel chains fell 5.7 percent, on top of an 11.3 percent decrease last year. Rao noted that the apparel chains showed improvement over the holiday weekend, as shoppers scooped up discounted items, resulting in flat sales on Black Friday compared with a year ago.

But department stores suffered an 8.6 percent drop in November, on top of a 6.3 percent decline last year. On Black Friday, sales for this sector fell four percent.