p13: The CARs are measured using the single index market model (SIMM). The SIMM parameters are  estimated over the pre event estimation period extending from day -210 to day -31. + p11: The market-modelparametersareestimatedusingtheCRSPequal-weighted indexovertheestimationperiodextendingfrom-210trading days priortotheproxymailingdateto-31daysprior,resultingina 180-day estimationperiodforeachfirm.WethencalculatedCARsfor various windowsaroundtheproxymailingdate.
p13: calpers; by event date