It is an object of the present invention to provide a maintenance service method capable of reducing the number of machine parts to be replaced while suppressing the number of times of failures of an apparatus even when an accurate failure probability distribution cannot be estimated concerning single machine parts. Solving means of the present invention is characterized by setting, according to at least one of a failure probability distribution and a performance deterioration probability distribution set for each of machine part types, the number of machine parts to be replaced, setting machine part replacement priority from at least one of the probability distribution and an operation situation or a machine part state, and listing, according to the machine part replacement priority, machine parts equivalent to the number of machine parts to be replaced.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A maintenance service method comprising: setting, according to at least one of a failure probability distribution and a performance deterioration probability distribution set for each of machine part types, a number of machine parts to be replaced; setting machine part replacement priority from at least one of the probability distribution and an operation situation or a machine part state; and listing, according to the machine part replacement priority, machine parts equivalent to the number of machine parts to be replaced. 2. The maintenance service method according to claim 2, further comprising learning at least one of the failure probability distribution and the performance deterioration probability distribution of the machine part type using maintenance history information indicating whether replacement of a machine part in actual maintenance work was necessary. 3. The maintenance service method according claim 1, wherein the number of machine parts to be replaced is calculated by calculating a failure rate in a maintenance schedule creation period from at least one of the failure probability distribution and the performance deterioration probability distribution set for each of the machine part types and integrating the failure ratio for each of the machine part types by a number of machine parts set as management targets. 4. The maintenance service method according to claim 3, wherein the machine part replacement priority is calculated by integrating the failure rate for each of the machine part types and the machine part state. 5. The maintenance service method according to claim 4, wherein a maintenance schedule of the machine parts to be listed is created. 6. A maintenance service system comprising: an apparatus information database that stores at least one of a failure probability distribution and a performance deterioration probability distribution set for each of machine part types; a maintenance history database that stores at least one of an operation information database that stores an operation situation and information concerning a machine part state; a machine-part-replacement-number calculating unit that calculates, according to at least one of the failure probability distribution and the performance deterioration probability distribution set for each of the machine part types, a number of machine parts to be replaced; and a machine-part-replacement-priority calculating unit that calculates machine part replacement priority using at least one of the probability distribution and the operation situation or the machine part state, wherein the maintenance service system lists machine parts equivalent to the number of machine parts to be replaced according to the machine part replacement priority. 7. The maintenance service system according to claim 6, wherein the maintenance service system learns at least one of the failure probability distribution and the performance deterioration probability distribution of the machine part type using maintenance history information indicating whether replacement of a machine part in actual maintenance work was necessary. 8. The maintenance service system according to claim 6, wherein the machine-part-replacement-number calculating unit calculates the number of machine parts to be replaced by calculating a failure rate in a maintenance schedule creation period from at least one of the failure probability distribution and the performance deterioration probability distribution set for each of the machine part types and integrating the failure ratio for each of the machine part types by a number of machine parts set as management targets. 9. The maintenance service system according to claim 8, wherein the machine-part-replacement-priority calculating unit calculates the machine part replacement priority by integrating the failure rate for each of the machine part types and the machine part state. 10. The maintenance service system according to claim 9, further comprising a maintenance-schedule creating unit that creates a maintenance schedule of the machine parts to be listed.