Connecticut Attorney General Richard Blumenthal says he will investigate Wal-Mart's pricing practices in the wake of studies showing significant discrepancies between the chain's posted and checkout prices.

Studies by the University of Illinois' Chicago Center for Urban Economic Development and the University of California-Berkley revealed that items purchased at Wal-Marts in Illinois, Michigan, Indiana and California scanned the wrong price as often as 8.3 percent of the time. That far exceeds the federal standard, a 2 percent error rate.

Errors recorded in the studies were both greater and less than the posted prices, so they sometimes benefited the consumer, other times the company.

Consumers have also complained to about pricing issues. Janice of Ellington, Mo., said the Poplar Bluff, Mo., Wal-Mart frequently has incorrect prices on its items.

"Checkers and managers get very nasty when you correct them. Why don't they fix the problem and correct the price?" she asked. "You can go back a week later and it most times is not taken care of so why get ugly with the customer?"

"I see this at Walmart all the time on all different types of products," said Maggi of Bloomington, Indiana. "How can they get away with that?"

Blumenthal will determine whether similar discrepancies exist at Wal-Mart stores in Connecticut.

"This data shows serious discrepancies between the prices posted and the amounts actually charged -- meriting prompt investigation -- because Wal-Mart has a legal obligation to be always accurate, not always low," Blumenthal said.

"Nothing is more fundamental to fair pricing than keeping promises about prices. Consumers should be spared a sweepstakes system when they come to the cash register. They deserve reliable, rock-solid price guarantees. The price they are given should be the price they are charged, he added.

"Consumers should take nothing for granted while shopping at Wal-Mart this holiday season. Check the register price with the shelve price and report any discrepancies to my office. Shoppers can be our eyes and ears, as we begin this investigation, according . to Blumenthal. "I will take appropriate action to protect consumers and assure the integrity of Wal-Mart's prices if my investigation uncovers unacceptable price inaccuracies in Connecticut."

The studies found that almost 85 percent of Wal-Mart stores surveyed in Illinois, Indiana and Michigan failed to meet the federally standard of a 2 percent error rate. In California, 87 percent of Wal-Marts surveyed exceeded the standard. The error rate was also highest in California -- 8.3 percent -- compared with 6.4 percent in the other three states.