[en] Estimation of temperature sensor characteristics by the noise analysis method is presented. Temperature fluctuations in hotleg and coldleg fluid during normal reactor operation are recorded and random data analysis techniques are applied to obtain information about the sensor performance. The noise signal is modeled using an autoregressive time series modeling strategy. The model evaluation consists of the following four steps: (1) estimation of model parameters; (2) selection of optimal model order, n; (3) model validation to check for the assumptions made in the analysis, and (4) evaluation of sensor characteristics from the model