The changes dovetail with changes that 10 major Wall Street firms agreed to make this year in a $1.4-billion settlement with the Securities and Exchange Commission and the states.

The new demands from CalPERS, the largest public pension fund, include asking banks to establish written criteria to determine analysts' compensation, and creating committees to review changes in recommendations on buying or selling shares.

They also require banks to show the performance of their analysts on their Web sites each quarter.

Rob Feckner, head of the pension fund's investment committee, said the fund will work with smaller brokerages that may be struggling to comply.

"We understand these standards may be difficult to meet for small and emerging firms and we will consider alternatives that meet our standards of transparency and ethics," he said.