Abstract: An output voltage prediction system for a fuel cell includes: a storage unit that stores a relationship between a logarithm of a cumulative deterioration index amount and an output voltage of the fuel cell when an output current of the fuel cell is within a predetermined current range, the cumulative deterioration index amount being a cumulative amount of a deterioration index amount related to progress of deterioration of the fuel cell; an input data acquisition unit that acquires the cumulative deterioration index amount of the fuel cell as input data; and a prediction unit that converts the input data acquired by the input data acquisition unit into a logarithm and predicts the output voltage of the fuel cell based on the logarithm of the input data and the relationship stored in the storage unit.

Abstract: In estimation of a future state of a first product (an estimation-target individual), a first estimated extrapolation value is calculated from data (data 2) on a past side of data relevant to the first product, and a second estimated extrapolation value is calculated from data (data 1) relevant to a second product (a same-type different-individual of the estimation-target individual) that is different from the first product. A synthesis ratio between the first estimated extrapolation value and the second estimated extrapolation value is decided from data (data 3) on a present side of the data relevant to the first product, and an estimation value is calculated by performing synthesis between the first estimated extrapolation value and the second estimated extrapolation value based on the decided synthesis ratio.