STATE-MONITORING DEVICE AND STATE-MONITORING METHOD

A diagnosis-parameter calculation unit (907) calculates a diagnosis parameter in a second time period, based on sensing data obtained in the second time period. A characteristic-data input unit (104) obtains characteristic data representing characteristics of a monitoring target device in a first time period and the second time period, from a logger included in the monitoring target device. Using the characteristic data in the second time period and the diagnosis parameter in the second time period, a regression-model generation unit (105) generates a regression model representing a relationship between the characteristic data and the diagnosis parameter. Using the regression model, a diagnosis-parameter estimation unit (106) estimates a diagnosis parameter in the first time period, which corresponds to the characteristic data in the first time period. Using the diagnosis parameters in the first time period and the second time period, the diagnosis-criteria setting unit (109) sets diagnosis criteria.