The halo effect refers to a cognitive bias whereby the perception of a particular trait is influenced by the perception of the former traits in a sequence of interpretations.
Edward L. Thorndike was the first to support the halo effect with empirical research. People seem not to think of other individuals in mixed terms; instead we seem to see each person as roughly good or roughly bad across all categories of measurement.
Positive or negative opinion about a person based on an impression formed from performance in one area. For example, an interviewer might judge an applicant's entire potential for job performance on the basis of a single characteristic such as how well the applicant dresses or talks.
For example, a teacher who is rating a child according to ‘interest in learning English’ may give the child a higher rating because he or she is well behaved in class.