Assessment and development centers: judgment biases and risks of using idiographic and nomothetic approaches to collecting information on people to be evaluated and trained in organizations

Assessment center and development center are two procedures that organizations can use in order to evaluate and train people. They make use of different methods and techniques, some (i.e. interviews) descending from the so called idiographic (or clinical) approach, and some (i.e. standardized instruments) descending from the so called nomothetic (or psychometric) approach. The idea is that different methods and techniques allow assessors and decision makers to collect as much information as possible, in order to come to an integrated judgment of people to be evaluated. Regarding this idea, psychological research has already discovered that it is not the amount of information collected that makes the difference between expert and non-expert assessors and decision makers. Besides, too much information is difficult to manage; and while it increases the confidence of assessors and decision makers about their judgments, it unfortunately does not increase their accuracy as well, since relevant information is mixed with irrelevant one and this makes it difficult to decide which one to consider and which one not. So, the article wants to be a critical review of what psychological science has found, and not so recently, in the field of assessment and development of psychological characteristics, in terms of risks and biases. Finally, it wants to underline the fact that, in spite of risks and biases, nowadays different methods and techniques are actually used to assess one person’s psychological characteristics, which is certainly questionable but also methodologically appropriate if they are appropriately used.