A psychologist’s methods of measuring people’s personalities differ depending on the theory they believe the most strongly in 💭

Direct Observation

This is the classic sit-on-a-park-bench-and-watch-people-interact type assessment. It's basically people-watching. Behaviorists prefer this assessment technique. Behavioral assessments then record the frequency of a specific behavior during an observation. This is usually criticized of being highly subjective, but it does lend a good hand in making inferences about behavior. However, during lab studies, this method can prove to be not so great because of the Hawthorn effect. The Hawthorn effect states that when people know they are being watched, they tend to change their behavior to what they think the observer is expecting. So when using this assessment technique, it's important to use controls. 

Projective Tests

Projective tests include asking people to interpret vague, ambiguous stimuli that have more than one meaning. Test-takers reveal inner thoughts that wouldn't have been revealed simply through their interpretation of the stimuli. There are two different types that you should be familiar with:

• Rorschach inkblot test is where a psychologist shows people a series of inkblots and asks them to describe what they see. It is the most commonly used projective test, and they aren't really reliable.
  

Image Courtesy of Wikipedia.

• The thematic apperception test (TAT) consists of a number of cards that each contain a picture of a person or people in a situation. These are also open to more than one interpretation and participants are asked to tell a story of what is happening in the picture, what led up to it, what people are feeling, etc. to reveal their inner thoughts.

Personality Inventories

Self-report inventories, or personality inventories, are questionnaires that ask people to provide information about themselves. There are so many different traits that could be gathered from these questionnaires, and psychologists created different versions of them.

One main personality inventory test you should know is the minnesota multiphasic personality inventory(MMPI). It is the most widely used self-report instrument that has lie detector questions built into the inventory to prevent deception and social desirability. It is used in just about any realm of personality and our everyday lives that you could think of.

Overview of Research Methods

Table Courtesy of Christiana Cobb. All credit to Myers' AP Psychology

🎥 Watch: AP Psychology—Personality Theories 

🏆 Trivia—Personality, Motivation, and Emotion