SAN FRANCISCO  Yahoo said Tuesday that it would cut 1,000 jobs from its 14,300-member work force by mid-February in an effort to cut costs and focus on its most important businesses.

The company disclosed the cuts during a discussion of its fourth-quarter earnings and a forecast of continued tough times ahead. The company did not specify which areas of the company would suffer layoffs.

Yahoo executives also said that the company planned to invest heavily in some areas, and that laid-off employees would be allowed to apply for jobs in those areas. The net effect on head count at the company was not clear.

“We are going to have to see how that is going to play out,” said John Aiken, an analyst with Majestic Research, a New York investment analysis firm.