Marin County Employees Retirement Association, San Rafael, Calif., selected market-neutral managers Analytic Investors, Fidelity Investments and Numeric Investors to run $10 million each, subject to contract negotiations, according to sources. The firms would be the first market-neutral managers for the $915 million pension plan. Cash in the portfolio will be equitized, giving the fund market returns plus excess returns from stock picking. Assets will be taken from a $53 million Barclays Global Investors S&P 500 commingled index fund. Callan was the consultant.