How Do Psychologists Measure Personality?

Your personality is a collection of attitudes, emotions, thoughts and behaviors. Personality helps to determine how you interact with other people and decide what motivates you. Psychologists have designed methods and tests in attempts to describe a person's personality type, or personality. Such tests reflect theoretical ideas about the nature of personality. In some tests, the focus is on genetic factors, while others stress environmental factors.

Personality Theories

• You can distinguish four different approaches to personality -- psychoanalytic, trait, social-cognitive and humanistic. The psychoanalytic approach stresses that personality is the product of innate, often unconscious forces. The trait theory describes personality as biological, while social-cognitive theories stress the interaction between the environment and a person's thoughts. Finally, the humanistic approach focuses on an individual's personal choices. No theory can explain personality, though, and psychologists often use a range of tests to measure personality. The theoretical assumptions behind a test influence the design of the test, and different tests measure different aspects of personality. Psychological measurement should be reliable, and the results should be stable over time. The tests should also measure personality and not other contributing factors.

Projective Tests

• The psychoanalytic approach uses projective tests to find out the person's unconscious urges and desires. A person can reveal her personality when she describes pictures. The Rorschach test uses ambiguous inkblots: the person being tested describes what image she can see in each abstract inkblot. In a variation of Rorschach tests, a person tells a story about a picture. Interpreting the results of these kinds of measurements is difficult since they are analysed for the meaning that a person ascribes to a picture rather than a predetermined standardized meaning.

Personality Inventory

• Personality can be measured by using a test where a person describes himself. Often a list of characteristics is used and the person has to decide which characteristics describes him. A problem with these kind of tests it that a person may not be honest when he answers the questions. "The Big Five" is a common personality trait test used to access the degree of a person's openness, conscientiousness, extraversion, agreeableness and neuroticism. These traits are determined through a statistical procedure analyzing how ratings of various personality traits are correlated in humans.

Observation and Interview

• Direct observation about how a person acts and behaves in certain situations provides insight into her personality. This approach makes it possible to study the influences of environment on personality. The presence of an observer, however, may influence and change a person's behavior, which makes it difficult to interpret the results. Interviewing a person about how she behaves in certain situations is another way of measuring personality. Structured interviews, in which a number of fixed questions are asked, are one method, while unstructured interviews, whereby the interviewer asks questions about any material that comes up during the interview, are preferred by some. Some psychoanalysts ask about dreams and childhood experiences to draw insight into personality. A humanistic personality analyst would explore a person's perceptions about reality and what choices he can make.