NEW YORK » Wall Street spent another session buffeted by volatility yesterday, this time closing mixed after investors wrestled with their fears about the economy but also looked for bargains after two days of selling. While the Dow Jones industrials and Standard & Poor's 500 index rose sharply, a downdraft in tech stocks left the Nasdaq composite index with a loss.

Buying came in spurts and then tended to quickly evaporate as investors fretted that the economy is either in a recession or headed for one. They showed little confidence, gravitating toward big-name stocks seen as safer bets after a two-day selloff sliced nearly 750 points from the Dow.

A snapshot of the labor market highlighted one of investors' worries about the fragility of the economy. The Labor Department reported yesterday that new applications for unemployment benefits rose 15,000 last week to a seasonally adjusted 478,000. That was slightly above analysts' estimates of 470,000. Jobless claims above 400,000 are considered a sign of recession.

The Dow rose 172.04, or 2.02 percent, to 8,691.25, after rising 277 points and falling by 276 points during the session.

Broader stock indicators were mixed yesterday. The Standard & Poor's 500 index rose 11.33, or 1.26 percent, to 908.11, and the Nasdaq fell 11.84, or 0.73 percent, to 1,603.91.

The Russell 2000 index of smaller companies fell 12.05, or 2.40 percent, to 489.92.

While the major indexes were mixed, declining issues outnumbered advancers by about 5 to 3 on the New York Stock Exchange, where consolidated volume came to 7.05 billion shares compared with 6.60 billion shares traded Wednesday.

An auction of $988 million in debt from failed bank Washington Mutual Inc. fetched a substantially higher price than was seen for a similar auction of Lehman Brothers debt earlier in the month. The sale priced $988 million of WaMu debt at 57 cents for every $1 of debt sold compared with the 8.625 cents on the dollar that a $4.92 billion sale of Lehman debt garnered.

The rate on three-month loans in dollars - known as the London Interbank Offered Rate, or Libor - was unchanged at 3.54 percent. The rate fell to that level on Wednesday and is the lowest since Sept. 24.

The three-month bill, regarded as the safest assets around, yielded 0.94 percent, down from 1.01 percent late Wednesday. Last week the yield was at 0.20 percent.

The yield on the benchmark 10-year Treasury note, which moves opposite its price, rose to 3.66 percent from 3.60 percent late Wednesday.

The dollar was mixed against other currencies after jumping to multiyear highs Wednesday, while gold prices fell.

Light, sweet crude rose $1.09 to settle at $67.84 on the New York Mercantile Exchange. The contract fell to a 16-month low on Wednesday as an increase in U.S. crude and gasoline stocks fed beliefs that weakness in the economy is eroding demand for energy.