Faced with opposition from advocacy groups and allegations of misleading statistical models, the UC Board of Regents has twice postponed voting on a controversial proposal to raise the grades students need to apply to the university.

However, the board approved several other “procedural adjustments,” which will take effect immediately but have little practical impact on students applying to the University of California this fall, in an attempt to reduce the number of students eligible for admission to the state’s most prestigious public university.

The proposals have come as a result of a May study by the California Postsecondary Education Commission, which found that too many of the state’s seniors meet the university’s minimum application requirements.

Under the state’s Master Plan for Higher Education, a blueprint outlining the role of California’s university and college institutions, the UC system must select from the state’s top 12.5 percent; CPEC found that more than 14 percent are eligible for admission.

In response, the UC faculty-run Academic Senate has approved a plan to reduce the eligibility rate to Master Plan levels, a move critics have said will hurt the poor and racial minorities. Groups like the UC Student Association have also criticized the board for first taking up the issue at its July hearing, when few affected students knew of the event or were able to attend.

“It was not open, it was not healthy for the university and it definitely did not allow all of the stakeholders to voice their opinions before the changes were made,” UCSA President Jennifer Lilla said.

While it approved changes in the way the system calculates GPAs of applicants at the time, the board decided to postpone its vote on whether to raise the minimum GPA needed for UC eligibility from 2.7 to 3.1 until a special August session at the request of some Regents. In August, the UC Office of the President announced that the vote would be postponed again until the board meeting in late September.

In July, a separate Regents’ committee on admissions voted in favor of all changes, leaving the GPA hike one step away from approval by the full board.

“It seemed like we needed a little more time for discussion,” said Student Regent Jodi L. Andersen, one of only two committee members voting against sending the changes to a full-board vote.

The Greenlining Institute, a liberal Berkeley-based think tank, and various other students spoke out against raising grade requirements at the July meeting, arguing that the new standards would disproportionately hurt the students already most underrepresented on UC campuses.

Admitting that minorities would feel a bigger burden than white students, UCSD chemistry professor Barbara Sawrey said the plan was the best the Academic Senate could come up with. She said that the plan would have the “least negative impact” on under-represented student groups. Sawrey chaired the senate’s admissions committee that wrote the recommendations.

“What we were looking for was a way that was fair to everybody,” she said.

Lawrence Pitts, the chair of the senate’s Academic Council, also backed the plan.

“Reducing the size of our eligibility pool is not a happy task, because we all know that access to a high-quality college education is critical to the future of California and its people,” Pitts told the regents in July. “But the faculty have worked to craft a proposal that achieves this reduction sensibly, by placing a priority on academic achievement in school and avoiding a dramatic impact on any single group of students.”

However, Lilla and others criticized the recommendations for disregarding the large margin of error in the CPEC report on which the proposal is based. Because the state commission used a sample of only 48 schools to estimate eligibility for 1,005 public high schools in California, its data calculated only a rough estimate for the actual eligibility rate of seniors.

Retired UC Berkeley physicist Charles Schwartz, a known critic of the board, told the Regents that the data had such high potential for error, it was uncertain whether the GPA hike was needed to bring eligibility down to 12.5 percent. He questioned why the recommendations presented to the regents left out that there was a 40-percent chance the actual eligibility rate was low enough to make the minimum grade changes unnecessary, according to the statistical model in the CPEC study.

“The thing that really upsets me most of all is that there is absolutely no mention, no discussion of that very standard professional question of uncertainty of data in any of the UC reports produced by the Academic Senate for the Board,” Schwartz said. “It is unprofessional to the extreme. If this was an oversight, well then someone should be embarrassed and fix it. If this was the deliberate suppression of things that might create too much discussion, then it is gross dishonesty, and that is really bad.”

The authors of the plan also used other data to verify the estimate and came up with the same numbers, Sawrey said in defense of the plan. She also explained that under the proposal, minimum grades would not be raised until 2006, giving UC administrators plenty of time to make final adjustments as more accurate data became available.

By approving the new requirements early, students will have an opportunity to raise their own grades to meet the tougher standards, Sawrey said.

The regents are expected to decide whether to go ahead with the plan at their meetings scheduled for Sept. 22 and Sept. 23.