1. A method for improving operational data measurements in an apparatus having a monitoring system, said monitoring system comprising a plurality of sensors, said method comprising: receiving from a sensor in said plurality of sensors a measurement by said sensor of an observed condition of said apparatus; determining, via said monitoring system, a confidence level for said sensor as a function of said measurement; determining, via said monitoring system, an estimate of said measurement as a function of said confidence level; and using said estimate of said measurement for fault detection in said apparatus.