Choose the philosophy to fit the task

The frequentist and subjectivist approaches both have valid theoretical bases. Either may be used in principle, if it is used carefully. In particular application, however, one approach may provide a more workable methodology than the other, or the customer may state a preference for one approach. Two such examples are given. The first is a safety assessment of welded joints at a nuclear power plant. This uses a frequentist approach. The second is an analysis of a proposed radioactive waste burial facility where a subjectivist approach is used. Once the philosophical approach has been selected, it must by followed consistently to ensure correct interpretation of the final results. (author)