Accuracy and reliability
(Cronbach’s alpha)
Estimating the reliability of a scale is based on the correlations between the measurements or items of the scale that make up the scale in relation to the variance of the items. Each measurement consists of a true result for a given concept or phrase, but also an unknown random error. The more a measurement reflects mostly the true result, the more reliable it is. Therefore, the final result is influenced by the number of concepts or phrases – a larger number of scale elements used makes it ultimately more reliable (measures a given phenomenon more accurately).
This is an important reservation from the point of view of the number of features and the number of expressions proposed in the developed psychometric tests. Well, each feature consists of 6 phrases that measure the candidate’s competence in a given area. It’s not much at all. At the same time, the level of final matching to a given job is measured not by one feature, but by 5-7 features, so ultimately it is a scale of 30-42 phrases.
