By Kate Gibson

The U.S. stock market's volatile display on Friday is likely to continue, reflecting limited volume as well as investors' concentration on only a handful of stocks, with the financial sector the scene of most of the recent action.

"While volume is light right now, volatility is quite high so we could see some wild swings in prices if buying and selling programs kick in," said Kevin Giddis, an analyst at Morgan Keegan & Co.

On Friday, information-technology and financial shares led the gains and health care and consumer staples fronted the losses as the market veered in a mixed pattern.

At 11:45 a.m. Eastern, the Dow Jones Industrial Average (DJI) was off 37.72 points, or 0.4%, at 9,542.91. The S&P 500 Index (SPX) declined 2.17 points, or 0.2%, to stand at 1,028.81, while the technology-laden Nasdaq Composite (RIXF) climbed 5.25 points, or 0.3%, to 2,032.98.

"Wall Street will most likely be a quiet, lonely pace by noon. This is normal for a late august Friday as traders head for the Hamptons, Cape Cod or other summer resort locations," said Fred Dickson, chief market strategist at Davidson Cos.

"Next week should even be quieter as professional investors normally take the last week of August for vacation ahead of the long Labor Day weekend and the beginning of the school year for many parts of the country," he added.

"On Monday just three stocks represented 34% of total stock market volume, while yesterday five stocks garnered the lion's share of the activity," noted William O'Donnell, an RBS Securities analyst, in an early note.

On Wednesday, Citigroup (C), Fannie Mae (FNM), Freddie Mac (FRE) and Bank of America (BAC) topped the list of most actively traded stocks, with American International Group (AIG) also qualifying as a regular on the list this month, according to the Wall Street Journal. .

Howard Silverblatt, senior index analyst at Standard & Poor's, said AIG is on its way to be the month's best performer on the S&P 500 -- with the stock up fully 266% for the month to date as of Thursday's close.

Since Aug. 5, trading in the aforementioned five stocks has averaged about 31.5% of the New York Stock Exchange's consolidated volume, the Journal reported.

The week ahead is called "Junior Traders Week" by many as large brokerages firms as senior traders take a break "ahead of what normally is a difficult month for the markets. Trading volume by and large dries up in tandem with the news flow," said Dickson.