1. An electronically-implemented model association method for updating estimation models used for system monitoring, the method comprising: for each of a plurality of monitored systems, determining an association between a particular monitored system and at least one of a plurality of estimation models, wherein each estimation model is based upon one of a plurality of distinct sets of estimation properties and wherein each set uniquely corresponds to a particular estimation model; updating at least one of the estimation properties; propagating the at least one updated estimation property to each estimation model that corresponds to a distinct set containing the at least one estimation property that is updated; and modifying each estimation model that corresponds to a distinct set containing the at least one estimation property that is updated.