Yahoo! Inc. Chief Executive Officer Carol Bartz said social networking leader Facebook Inc. has emerged as a bigger rival than Google Inc., owner of the biggest Web-search engine.

      “Our greatest competitor probably is Facebook, more so than Google,” Bartz said at a presentation in New York yesterday. “They’re a hot site, but there’s room for more than one of anything.”

      Bartz said her company once weighed buying privately held Facebook for about $1 billion and that her acquisition strategy is to focus on companies that bring users, content, engineers and advertising technology. Yahoo is adding features to keep from using Web surfers to sites such as Facebook and Twitter Inc. that make it easier to interact with friends.

      The second-year CEO has cut costs, pared extraneous products and focused Yahoo on news, sports and other content. She also struck a partnership that lets Microsoft Corp. handle the mechanics of Web search, while Yahoo oversees advertising sales. She’s been less successful reviving growth and keeping pace with newer, faster-growing Web companies.

      As Facebook’s user base has surged past 500 million, its value has risen to more than $40 billion, according to private- share trading site SharesPost Inc. Yahoo, based in Sunnyvale, California, has a market capitalization of $22.1 billion.

      Asked for her thoughts on whether Yahoo should go private, Bartz said she has no plans to do so. She also said Yahoo will remain useful to users because of its ability to personalize and organize content from the Web’s 240 million sites.

      “For the most part, people pretty much want this curated for them,” she said.

      Yahoo rose 61 cents, or 3.7 percent, to $16.94 yesterday on the Nasdaq Stock Market. The shares are little changed this year before today.