Unit 12 Mod 34 36 1 Unit 12 Personality Module 34 Personality and Behavior Approaches and Measurement Early Approaches to Assessing Personality Identical twins reunited after 35 years both had gone to graduate school in film They both loved to write and they had both edited their high school yearbooks They have similar music taste They wrote a book called identical strangers One of the most fundamental tendencies of human beings is to size up other people When we make these statements we mean that we believe that these people have stable individual characteristics their personalities Personality an individual s consistent patterns of feeling thinking and behaving The tendency to perceive personality is a fundamental part of human nature and a most adaptive one If we can draw accurate generalizations about what other people are normally like we can predict how they will behave in the future and how they are likely to respond in situations Understanding personality can help us understand psychological disorders and the negative behavioral outcomes they may produce Early theories assumed that personality was expressed in people s physical appearance One early approach by Franz Joseph Gall was phrenology and was based on the idea that we could measure personality by assessing the patterns of bumps on people s skulls In the Victorian age phrenology was taken seriously and many people promoted its use as a source of psychological insight and selfknowledge Machines were even developed Because careful scientific research did not validate the predictions of the theory phrenology has now been discredited in contemporary psychology Another approach known as somatology by William Herbert Sheldon was based on the idea that we could determine personality from people s body types Sheldon argued that people with more body fat and a rounder physique endomorphs were more likely to be assertive and bold whereas thinner people ectomorphs were more likely to be introverted and intellectual Scientific research did not validate the predictions and has now been discredited in contemporary psychology Another approach is known as physiognomy or the idea that it is possible to assess personality from facial characteristics Contemporary research has found that people are able to detect some aspects of a person s character whether they are gay or straight and whether they are Democrats or Republicans at above chance levels by looking at the face The ability to detect personality from faces is not guaranteed Olivola and Todorov recently studied the ability of thousands of people to guess the personality characteristics of hundreds of thousands of faces on the website In contrast to the predictions of physiognomy the researchers found that these people would have made more accurate Unit 12 Mod 34 36 2 judgments about the strangers if they had just guessed using their expectations about what people in general are like rather than trying to use the particular facial features of individuals to help them It seems then that the predictions of physiognomy may also in the end find little empirical support Personality as Traits Personalities are characterized in terms of traits Personality traits such as introversion friendliness conscientiousness honesty and helpfulness are important because they help explain consistencies in behavior Traits relatively enduring characteristics that influence our behavior across many situations The most popular way of measuring traits is by personality tests on which people self report about their own characteristics Psychologists have investigated hundreds of traits using this approach and research has found many personality traits that have important implications for behavior Example of a trait measure As with intelligence tests the utility of self report measures of personality depends on their reliability and construct validity The Myers Briggs Type Indicator MBTI is the most widely administered personality test in the world given millions of times a year to employees in thousands of companies It categorizes people into one of four categories on each of four dimensions introversion versus extroversion sensing versus intuiting thinking versus feeling and judging versus perceiving Although completing the MBTI can be useful for helping people think about individual differences in personality and for breaking the ice at meetings the measure itself is not psychologically useful because it is not reliable or valid People s classifications change over time and scores on the MBTI do not relate to other measures of personality or to behavior Measures such as the MBTI remind us that it is important to scientifically and empirically test the effectiveness of personality tests by assessing their stability over time and their ability to predict behavior Unit 12 Mod 34 36 3 One of the challenges of the trait approach to personality is that there are so many of them at least 18 000 words can be used to describe people A major goal of psychologists is to take this vast number of descriptors and determine the underlying core traits among them The trait approach to personality was pioneered by Gordon Allport Raymond Cattell and Hans Eysenck Each of these psychologists believed in the idea of the trait as the stable unit of personality and attempted to provide a list or taxonomy of the most important trait dimensions Their approach was to provide people with a self report measure and then to use statistical analyses to look for the underlying factors clusters of traits according to the frequency and the co occurrence of traits in the respondents Allport began his work by reducing the traits to a set of 4 500 trait like words that he organized into three levels according to their importance He called them cardinal traits the most important traits central traits the basic and most useful traits and secondary traits the less obvious and less consistent ones Cattell used a statistical procedure known as factor analysis to analyze the correlations among traits and to identify the most important ones He identified what he called source more important and surface less important traits and he developed a measure that assesses 16 dimensions of traits based on personality adjectives taken from everyday language Hans Eysenck was interested in the biological and genetic origins of personality and made an important contribution to understanding the nature of a fundamental personality trait extroversion versus