PSYCHOLOGICAL TESTING

Psychological Testing

Psychological Testing

Introduction

As a technical term, 'psychological testing' refers to methods developed to describe, record, and interpret a person' behavior, be it with respect to underlying basic dispositions to characteristics of state or change, or to such external criteria as expected success in a given training curriculum or in psychotherapeutic treatment (Anastasi,, 1988). Methods of psychological testing constitute a major technology that grew out of psychological research, with widespread impact in educational, clinical, and industrial/organizational psychology, in counseling and, last but not least, in research itself.

Discussion

In the most general sense, all testing methods share one common feature: they are designed so as to capture the enormous variability (between individuals or within a single individual) in kind and properties of behavior and to relate these observed variations to explanatory dimensions or to external criteria of psychological intervention and prediction. As a distinct field of psychology, psychological testing comprises of:

(1) A wide range of instruments for observing, recording, and analyzing behavioral variations;

(2) Formalized theories of psychological measurement underlying the design of these methods; and, finally,

(3) Systematic methods of psycho-diagnostic inference in interpreting testing results (Anastasi,, 1988).

Reliability

This core psychometric criterion is defined as the extent to which testing results are unchanged by random errors of examination, of testing conditions, and measurement mistakes. Reliability i.e. R is the nucleus concept of the so-called classical test theory or CTT. According to this theory any measured score x is the total of two fundamental constituents: a true score t (of that person in the underlying behavior variable) plus an error component e (due to unintended, unsystematic causes of variation additionally affecting that person' behavior at that given testing occasion). Then reliability is described as the proportion of the variance of the true score constituent to the variance of measured scores x. In this sense, the reliability coefficient R denotes the percentage of variance in observed ...