A device and method for providing a load calculating device is presented. In one embodiment, a load calculating device can include a variable acquiring unit configured to acquire monitoring variables. The monitoring variables can include in a detected value by a sensor monitoring a state of a circuit board and a performance characteristic obtained by a tool monitoring performance of the circuit board. The device can also store a first statistical model that is one of a regression model, an occurrence frequency distribution and a probability distribution; a second storage configured to store a second statistical model that is one of a regression model, an occurrence frequency distribution and a probability distribution. An arithmetic processor can then be used to calculate the intermediate variable from the monitoring variables according to the first statistical model and calculate the physical quantity from calculated intermediate variable according to the second statistical model.