NEW YORK - Investors sidestepped some of their doubts about the strength of an economic recovery and pushed into energy, industrial and materials stocks as commodity prices rose.

Stocks zigzagged in a tight range Tuesday as the day's news on corporate dealmaking failed to extend a strong advance from Monday. It wasn't until the gains in commodity prices that stocks began to pare early losses.

Investors drew some comfort from billionaire investor Warren Buffett's decision to pay $100 a share for Burlington Northern Santa Fe in a deal valuing the railroad at $34 billion.

Meanwhile, tool maker Stanley Works agreed to acquire Black & Decker Corp. for $3.46 billion in stock.

Commodities rose broadly and gold jumped to a new high after India's central bank bought $6.7 billion worth of gold from the International Monetary Fund.

Even with the gains in commodities, traders remain on edge about unemployment and the overall strength of an economic recovery.

Health care products maker Johnson & Johnson said it would cut up to 7 percent of its global work force and streamline its business structure to save up to $900 million next year.

Investors were unnerved by further efforts to restructure two of the U.K.'s largest banks. The Royal Bank of Scotland got a $41 billion infusion from the government, while Lloyds said it was looking to raise about $34 billion through a share issuance.

Traders have been uneasy in recent weeks, wary about whether the economic recovery can maintain the same pace once government stimulus measures are removed. That uncertainty has led to wild swings in the market. The Dow Jones industrial average has risen or fallen more than 100 points in six of the last eight trading days, the most volatility since March.

Thomas Ruggie, president of Ruggie Wealth Management in Tavares, Fla., said investors are worried that the stock market has been getting overheated so they're not moving into stocks even when there is upbeat news like merger activity.

"People are still scared," he said. "People are treading very, very lightly."

In late afternoon trading, the Dow fell 48.97, or 0.5 percent, to 9,740.47, after being down as much as 86 points. The Dow rose 77 points Monday.

The broader Standard & Poor's 500 index rose 0.62, or 0.1 percent, to 1,043.50.