Groundmotionsintensitymeasures(IMs)aretypicallyestimatedusingprobabilisticseismic hazardanalyses(PSHA),whichcombinetheeffectsofsource,path,andsiteontheIM.Hazard analysesuseattenuationrelationshipstodefinetheprobabilitydensityfunction(PDF)forIM conditionedoneart