Erratic measure

The paper exposes an inconsistency in the field of nondestructive examination (NDE) and points out the dangers of the confusion which is created by it. The physical objects which occupy a statistical population occupy a partition of the complete set of physical objects under consideration. However, many of NDE's procedures test physical objects which do not occupy such a partition. The inconsistency is set up when NDE's scientists represent physical objects which do not occupy partitions as the elements of populations in their studies of NDE's reliability. The bogus populations invalidate the definition of probability as a measure of an event whose value on a certain event is 1. With probability invalidated as a measure of a test's reliability, NDE's scientists have proceeded by representing a different measure of an event as a probability. The value of this measure on a certain event varies between 0 and 2 in one US Nuclear Regulatory Commission study. This makes the reader who interprets the study's measure as a probability wrong on a number of counts. For example, the apparently perfect certainty which accompanies a value of 1 for the study's Probability of Detection is actually perfect ambiguity because this measure's value on the certain event of a defect is 2. Dire consequences are imaginable if a reactor engineer were to act on the USNRC's representation. The authors recommend avoidance of the consequences of this and other instances of confusion by the translation of past reporting. The translated reports would use a language which discriminated proper from improper probabilities and populations. For the longer term, they recommend the refocusing of NDE to yield only proper probabilities and populations