A definition of reliability
Reliability of scores from selection measures is a characteristic necessary for effective HR selection. In our earlier example, the computer programming aptitude test was apparently a unreliable measure; it is this unreliability in test scores that makes it difficult for Robert to know each applicant's actual level of programming aptitude. A host of definitions have beengiven for the term relicability. In our discussion, we will touch on several of these. But for now we want to consider a fundamental definition of the concept. In the context of HR selection, RELIABILITY simply means the degree of dependability, consistency or stability of SCORES on a MEASURE used in selection researchg (either predictors or criteria). In general, reliability of a measure is determined by the degree of consistency between two sets of scores on the measure. In our earlier selection example, we would have expected the programming aptitude test to have yielded similar results from one testing period to the next if the test produced reliable data. Because the results were not similar, we would probably conclude that the test contained errors of measurement. Thus a careful study of the reliability of the test should be made.