Investors sidestepped some of their doubts about the economy and bought energy and industrial stocks as commodity prices rose.
Stocks ended back-and-forth trading mostly higher on Tuesday as a spike in the price of gold and corporate dealmaking extended an advance from Monday. The gains in commodity prices helped stocks pare early losses.
The Dow Jones industrial average slipped 17 points, while broader indexes rose modestly.
Investors were encouraged by billionaire investor Warren Buffett's decision to pay $34 billion for the railroad Burlington Northern Santa Fe in what he termed an "all-in wager" on the future of the U.S. economy. Meanwhile, tool maker Stanley Works struck a deal to acquire Black & Decker Corp. for $3.46 billion in stock.
Investors also took cues from commodities including gold, which jumped to a new high after India's central bank bought $6.7 billion worth of the metal from the International Monetary Fund.
Still, even with the gains in commodities, traders remained on edge about unemployment and the strength of an economic recovery.
Concerns about unemployment grew after 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 worry high unemployment will make it hard for the economy to sustain recent growth.
Financial stocks fell after the British government injected more money into Royal Bank of Scotland PLC and Lloyds Group PLC. That fanned worries about the troubles with bad debt still facing many banks.
Traders have been uneasy in recent weeks, wary about whether the economic recovery can maintain its third-quarter growth once government stimulus measures are removed. The Commerce Department said last week the economy grew at an annual rate of 3.5 percent during the summer.
The uncertainty about the economy has led to swings in the market. The Dow has risen or fallen more than 100 points in six of the last eight trading days, the most volatility since March.
Analysts said a break in the advance could ease worries that the market has advanced too quickly.
"This is a much-needed healthy pause and reassessment. It ran so far," said David Darst, chief investment strategist for Morgan Stanley Smith Barney in New York.
The Dow fell 17.53, or 0.2 percent, to 9,771.91, after being down as much as 86 points. The Dow rose 77 points Monday following reports of improvements in manufacturing and housing.
The broader Standard & Poor's 500 index rose 2.53, or 0.2 percent, to 1,045.41. The index is up 54.5 percent from a 12-year low in early March.
The Nasdaq composite index rose 8.12, or 0.4 percent, to 2,057.32.
"We're seeing a natural ebb and flow of risk appetite," said Kevin Gardiner, head of investment strategy for Europe, Middle East and Africa at Barclays Wealth.
Analysts expect trading to be choppy this week, as investors digest a frenzy economic reports. Investors are watching the Federal Reserve, which concludes a two-day meeting Wednesday, for any clues about the economy and the direction of interest rates.
Investors also looked past increases in automobile sales. Ford Motor Co. said sales rose 3 percent from October last year, while General Motors Corp.'s sales rose 4.7 percent. It was the first monthly sales increase for the nation's largest automaker since January 2008. Meanwhile, Chrysler's sales fell 30 percent, though they improved from September.
Bond prices fell as stocks rose, pushing yields higher. The yield on the benchmark 10-year Treasury note rose to 3.47 percent from 3.42 percent late Monday.
The dollar was mixed against other major currencies.
Crude oil rose $1.47 to settle at $79.60 a barrel on the New York Mercantile Exchange, while gold surged to a new high of $1,087 an ounce.
Shares of Burlington Northern jumped $20.93, or 27.5 percent, to $97 after the move by Buffett's Berkshire Hathaway Inc., which already owns about 22 percent of Burlington.
That pulled other railroads higher. CSX Corp. rose $3.13, or 7.3 percent, to $45.97, while Norfolk Southern Corp. advanced $2.52, or 5.4 percent, to $49.15.
Black & Decker jumped $14.66, or 31 percent, to $62, while Stanley Works rose $4.54, or 10.1 percent, to $49.69.
Johnson & Johnson fell 56 cents, or 0.9 percent, to $58.93.
Royal Bank of Scotland fell 69 cents, or 5.5 percent, to $11.96, while Lloyds rose 28 cents, or 5.2 percent, to $5.72.
The Russell 2000 index of smaller companies rose 8.22, or 1.5 percent, to 570.62.
Three stocks rose for every two that fell on the New York Stock Exchange, where consolidated volume came to 5.5 billion shares, compared with 6.3 billion Monday.
Overseas, Britain's FTSE 100 fell 1.3 percent, Germany's DAX index fell 1.4 percent, and France's CAC-40 dropped 1.5 percent. Markets in Japan were closed for a holiday.