1. A computer implemented method of evaluating a monitoring model of a power plant system or a magnetic resonance imaging system, comprising: obtaining a first set of test data from the system through at least one monitoring sensor, the first set of test data including a first plurality of negative data points; designating at least one of the first plurality of negative data points as a first positive data point; and performing a first receiver operating characteristics (ROC) analysis on the first set of test data to obtain a first receiver operating characteristics analysis curve to be used as at least a portion of the monitoring model for the first set of test data; selecting an evaluation criteria for the model wherein the evaluation criteria is based on the first ROC; evaluating the monitoring model of the power plant system or magnetic resonance imaging system based upon the selected evaluation criteria from the first receiver operating characteristic analysis curve; and monitoring operating condition of the power plant system or magnetic resonance imaging system using the evaluated monitoring model.