African Americans are far more likely to have bad credit records than whites, even when blacks and whites with similar incomes are compared, according to a study to be released today by Freddie Mac.

The study found that whites earning less than $25,000 had better credit records as a group than African Americans earning between $65,000 and $75,000. Overall, 48 percent of blacks and 27 percent of whites had bad credit ratings, as defined by Freddie Mac in this study.

While the study did not attempt to establish conclusively why the disparity exists, researchers conjecture that black Americans have fewer resources to fall back on in times of trouble. Cultural attitudes also contribute, they suspect: For example, it is known that people who believe they control their lives tend to budget better and save more. While credit reporting is supposed to be colorblind, some experts said that racism may contribute to the economic instability that leads to unpaid bills.

Freddie Mac, which is federally chartered to provide capital for mortgage lending, plans to use the results of the $1.3 million study and an in-depth survey of consumer knowledge and attitudes to develop a course intended to change behaviors. The NAACP, the National Urban League and five historically black colleges, including Howard University, will help develop and disseminate materials in the $2 million program.

The researchers, who examined the credit reports of a scientific sampling of more than 80,000 people, assigned a bad credit rating to anyone who in the last two years had two bills overdue more than 30 days, one bill more than 90 days late, a lien or judgment or a bankruptcy.

But lenders rely on a credit scoring model that considers more than just how late people are on their bills. Credit history is determined by factors including the borrower's repayment pattern, how long the borrower has had credit, the total amount of credit the borrower has access to and is using and whether the consumer is seeking credit from other sources. And the system is subjective. For example, it is up to creditors to report their customers' payment patterns.

"Blacks have been disadvantaged in many ways for a long time, and that is going to show up in credit reports," said Alicia Munnell, a Boston College professor who led a study of discrimination in lending for the Federal Reserve Bank of Boston.

Blacks, she noted, have had less time to accumulate a financial cushion. And their parents and other relatives are less likely to have the resources to help them during an economic crisis.

"The figures are quite stunning, and more startling than I would have expected," said Theodore Cross, author of "Black Capitalism" and editor of the Journal of Blacks in Higher Education.

Other studies, including a recent one by the federal Department of Housing and Urban Development, have documented racial discrimination in lending even among people with equal incomes and equally good credit ratings. The new study could conceivably be used by bankers to justify denying loans disproportionately to African Americans.

But Hugh Price, head of the Urban League, said such fears miss the point. "If people have bad credit, they'll be denied loans, end of story," Price said.

He added that continuing discrimination against minorities with good credit ratings must be addressed through stricter enforcement, but he added, "This study pinpoints another area that has to be addressed."

Cross said he was most disturbed by the statistics showing that 48 percent of African Americans with incomes between $45,000 and $65,000 had bad credit, compared with only 21.6 percent of whites. Hispanics in that bracket had a slightly worse record than whites -- 28 percent had credit problems. Only 15.7 percent of Asians with the same income had a bad credit rating.

These African Americans "are the heart of the American middle class, yet they are being determined poor credit risks at twice the rates of whites," Cross said.

While the credit reporting may have been colorblind, racism often plays an underlying role, said Thomas Shapiro, co-author of "Black Wealth/White Wealth: A New Perspective on Racial Inequality." For example, he said, many people get behind on their bills when they lose a job -- and black employees, he said, are often the first to be let go.

Leroy Hubbard, chairman of the D.C. Reinvestment Alliance, said that when blacks get in financial trouble, they are less likely to be able to get a loan to tide them over. Numerous studies also show that some lenders deny loans to black applicants with good credit histories. Cross suggested that such lenders are making assumptions similar to those made by police officers who stop black drivers more often than white drivers.

"If you pull over a black kid in a red sports car for no reasons except suspicion, it may not be constitutional, but it's rational," he said. That young man, he continued, is probably not carrying drugs, but he's more likely to be carrying drugs than a white woman in a van filled with children.

"But while it's rational," Cross added, "it's still racist."

Freddie Mac contracted with Market Facts, a leading survey company, to help conduct its study. In addition to reviewing credit reports, researchers gave a long questionnaire to 19,000 people to measure attitudes, knowledge and behavior.

Peter Zorn, a Freddie Mac researcher, said the group has not yet subjected the data to sophisticated analysis, but already is surprised by some preliminary findings.

"We expected there to be pretty significant differences of attitudes towards and knowledge about credit [among races], but we didn't find it," he said. "We are struck by the similarity in answers to things like, `How often do you buy products to impress others?' "

He said that whites seem slightly more knowledgeable than blacks about issues of personal finance but that neither group knows much.

Dwight Robinson, a senior vice president at Freddie Mac, noted that while Americans of all races are enjoying historic rates of homeownership, disparities remain. About 67 percent of whites own their own homes, and 45 percent of blacks.

"As we find solutions out of this" credit history disparity, he said, "obviously that can only be good for business at Freddie Mac."

The study also found that even the poorest Asians -- with incomes under $25,000 -- had credit records comparable to the wealthiest whites studied -- those with incomes between $65,000 and $75,000.

Only 12.5 percent of the wealthier Asians had credit problems, compared with 20.4 percent of the wealthier whites and 34.5 percent of wealthier blacks.

Previous studies have found that Asians save more than other groups, with whites coming in second. Black Americans have very low savings rates. In designing a course and other materials, Freddie Mac will work not only with the business departments of historically black colleges, but also with their sociology and psychology departments.

"We want to figure out all the things that might affect behaviors and ultimately credit, and focus on the things we can impact," Zorn said. Increasing homeownership among lower-income Americans and minorities is part of Freddie Mac's mission.

Zorn said that convincing people they have power over their lives may be as important as teaching them about the joys and horrors of compound interest.

Staff writer Michelle Singletary contributed to this report.