Personality test

A personality test aims to describe aspects of a person's character that remain stable throughout that person's lifetime, the individual's character pattern of behavior, thoughts, and feelings. An early model of personality was posited by Greek philosopher/physician Hippocrates. The 20th century heralded a new interest in defining and identifying separate personality types, in close correlation with the emergence of the field of psychology. As such, several distinct tests emerged; some attempt to identify specific characteristics, while others attempt to identify personality as a whole.

Overview
There are many different types of personality tests. Common personality tests consist of a large number of items, in which respondents must rate the applicability of each item to themselves. Projective tests, such as the TAT and Ink Blots are another form of personality test which attempt to assess personality indirectly.

Scoring
Personality tests can be scored using a dimensional (normative) or a typological (ipsative) approach. Dimensional approaches such as the Big 5 describe personality as a set of continuous dimensions on which individuals differ.

Typological approaches such as the Myers-Briggs Type Indicator (r) describe opposing categories of functioning where individuals differ. Normative responses for each category can be graphed as bell curves (normal curves), implying that some aspects of personality are better than others. Ipsative test responses offer two equally "good" responses between which an individual must choose. Such responses (e.g., on the MBTI) would result in bi-modal graphs for each category, rather than bell curves.

Personality tests such as the Strength Deployment Inventory (r), which assesses motivation, or purpose, of behavior, rather than the behavior itself, combine a dimensional and typological approach as described here. Three continuums of motivation are combined to yield 7 distinct types.

Many, but by no means all, psychological researchers believe that the dimensional approach is more accurate, although as judged by the popularity of the Myers-Briggs tool, typological approaches have substantial appeal as a self-development tool.

Personality tests, especially 5-Factor (Big Five personality traits), such as the NEO PIR, are extremely powerful. For a current bibliography see the NEO PIR Bibliography (Costa and McCrae, PAR, 2003). Just one article "The five-factor model of personality in the workplace" (Neubert) shows how the personality factors predict job satisfaction and performance.

Emotive tests could in theory become prey to unreliable results due to people striving to pick the answer they feel the best fitting of an ideal character and therefore not their true response. In practice, however, most people do not significantly distort. There may be several reasons for this, not the least of which is knowing what is "ideal." What is the ideal response set for an aircraft salesperson? Unless one knows how to sell aircraft it is unlikely they could dissemble appropriately.

Norms
The meaning of personality test scores are difficult to interpret in a direct sense. For this reason substantial effort is made by producers of personality tests to produce norms to provide a comparative basis for interpreting a respondent's test scores. Common formats for these norms include percentile ranks, z scores, sten scores, and other forms of standardised scores.

Test development
A substantial amount of research and thinking has gone into the topic of personality test development. Development of personality tests tends to be an iterative process whereby a test is progressively refined. Test development can proceed on theoretical or statistical grounds. Theoretical strategies can involve taking psychological or other theory to define the content domain and then developing test items that should in principle measure the domain of interest. This can then be accompanied by assessment by experts of the developed items to the defined construct. Statistical strategies are varied. Common strategies involve the use of exploratory factor analysis and confirmatory factor analysis to verify that items that are proposed to group together into factors actually do group together empirically. Reliability analysis and Item Response Theory are additional complimentary approaches.

Test evaluation
There are several criteria for evaluating a personality test. Fundamentally, a personality test is expected to demonstrate reliability and validity.

Biased test taker interpretation
One problem of a personality test is that the users of the test could only find it accurate because of the subjective validation involved. This is where the person only acknowledges the information that applies to him/her. This is related to what is called in psychology as the Forer effect.

Application to non-clinical samples
Critics have raised issues about the ethics of administering personality tests, especially for non-clinical uses. By the 1960s, tests like the MMPI were being given by companies to employees and applicants as often as to psychiatric patients. Sociologist William H. Whyte was among those who saw the tests as helping to create and perpetuate the oppressive groupthink of the "organization man" mid-20th century corporate capitalistic mentality.

This is still relevant to today's job market, where use of Unicru personality tests has become unpopular enough to create a demand for software applications to automate the process of filling them out.

Personality versus social factors
In the 60s and 70s some psychologists dismissed the whole idea of personality, considering much behaviour to be content specific. This idea was supported by the fact that personality often does not predict behaviour in specific contexts. However, more extensive research has showed than when behaviour is aggregated across contexts, that personality can be a modest to good predictor of behaviour. Almost all psychologists now acknowledge that both social and individual difference factors (i.e., personality) influence behaviour. The debate is currently more around the relative importance of each of these factors and how these factors interact.

Respondent faking
One problem with self-report measures of personality is that respondents are often able to distort their responses. This is particularly problematic in employment contexts and other contexts where important decisions are being made and there is an incentive to present oneself in a favourable manner. Work in experimental settings (e.g., Viswesvaran & Ones, 1999; Martin, Bowen & Hunt, 2002) has clearly shown that when student samples have been asked to deliberately fake on a personality test, they clearly demonstrated that they are capable of doing so.

Several strategies have been adopted for reducing respondent faking. One strategy involves providing a warning on the test that methods exist for detecting faking and that detection will result in negative consequences for the respondent (e.g., not being considered for the job). Forced choice item formats (ipsative testing) have been adopted which require respondents to choose between alternatives of equal social desirability. Social desirability and lie scales are often included which detect certain patterns of responses, although these are often confounded by true variability in social desirability. More recently, Item Response Theory approaches have been adopted with some success in identifying item response profiles that flag fakers. Other researchers are looking at the timing of responses on electronically administered tests to assess faking. And again, (see above), while people can fake in practice they seldom do so to any significant level. And again, to successfully fake means knowing what the ideal answer would be. Even with something as simple as assertiveness people who are unassertive and try to appear assertive often endorse the wrong items. Why? Because unassertive people confuse assertion with aggression, anger, oppositional behavior, etc.

Psychological Research
Personality testing is frequently used in psychological research to test various theories of personality.

Research published by David Dunning of Cornell University, Chip Heath of Stanford University and Jerry M. Suls of the University of Iowa reveals that observers who are not involved in any type of relationship with an individual are better judges of the individual's relationships and abilities. These workers have studied a large body of investigations into self-evaluation, indicating that individuals may have flawed views about themselves and their social relationships, sometimes leading to decisions that can impact negatively on other persons' lives and/or their own.

Additional applications
A study by American Management Association reveals that 39 percent of companies surveyed use personality testing as part of their hiring process. However, ipsative personality tests are often misused in recruitment and selection, where they are mistakenly treated as if they were normative measures. More people are using personality testing to evaluate their business partners, their dates and their spouses. Salespeople are using personality testing to better understand the needs of their customers and to gain a competitive edge in the closing of deals. College students have started to use personality testing to evaluate their roommates. Lawyers are beginning to use personality testing for criminal behavior analysis, litigation profiling, witness examination and jury selection.

Dangers of Such Practices
It is easy for personality test participants to become complacent about their own personal uniqueness and instead become dependent on the description associated with them. This can be potentially dangerous with persons who are already suffering from a form of identity disorder or may be a catalyst to instigate particular behaviors in a person who was previously believed to be of sound mental health. The severity of the damage that individuals can sustain to their personal identity was made clear during the case Wilson v Johnson&Johnson in which the plaintiff (Wilson) sued his former employer (Johnson&Johnson) for irreparable damages that resulted from the over abundance of personality tests being administered in the workplace. Wilson argued that repeated questioning and scrutiny of his personality was a cause of strain and eventually breakdown. In this historic case, Wilson was awarded $4.7 million after jurors agreed that excessive testing caused strain and led to unnecessary scrutiny resulting in personal grief. Similar cases have been tried since and won, but none with such magnitude as this first monumental case that won mental health rights for employees.

Examples of personality tests

 * The first modern personality test was the Woodworth Personal data sheet, which was first used in 1919. It was designed to help the United States Army screen out recruits who might be susceptible to shell shock.


 * The Rorschach inkblot test was introduced in 1921 as a way to determine personality by the interpretation of abstract inkblots.


 * The Thematic Apperception Test was commissioned by the Office of Strategic Services (O.S.S.) in the 1930s to identify personalities that might be susceptible to being turned by enemy intelligence.


 * The Minnesota Multiphasic Personality Inventory was published in 1942 as a way to aid in assessing psychopathology in a clinical setting.


 * Myers-Briggs Type Indicator is a 16-type indicator based on Carl Jung's Psychological Types, developed during World War II by Isabel Myers and Katherine Briggs.


 * Keirsey Temperament Sorter developed by David Keirsey is influenced by Isabel Myers sixteen types and Ernst Kretschmer's four types.


 * The 16PF Questionnaire (16PF) was developed by Raymond Cattell and his colleagues in the 1940s and 1950s in a search to try to discover the basic traits of human personality using scientific methodology. The test was first published in 1949, and is now in its 5th edition, published in 1994. It is used in a wide variety of settings for individual and marital counseling, career counseling and employee development, in educational settings, and for basic research.


 * The Five Factor Personality Inventory - Children (FFPI-C) was developed to measure personality traits in children based upon the Five Factor Model (Big Five personality traits).


 * The EQSQ Test developed by Professor Simon Baron-Cohen, Sally Wheelwright, and their team at the University of Cambridge, England, centers on the Empathizing-Systemizing theory of the male versus the female brain types.


 * The Personal Style Indicator (PSI) classifies four aspects of innate behavior by testing a person's preferences in word associations.


 * The Strength Deployment Inventory, developed by Elias Porter, Ph.D. in 1971 and is based on his theory of Relationship Awareness. Porter was the first known psychometrician to use colors (Red, Green and Blue) as shortcuts to communicate the results of a personality test.


 * The ProScan Survey is an instrument designed by Professional DynaMetric Programs, Inc. (PDP) to measure the major aspects of self-perception, including an individual’s basic behavior, reaction to environment, and predictable behavior. It was originally developed beginning in 1976 by Dr. Samuel R. Houston, Dr. Dudley Solomon, and Bruce M. Hubby.


 * The Newcastle Personality Assessor (NPA), created by Daniel Nettle, is a short questionnaire designed to quantify personality on five dimensions: Extraversion, Neuroticism, Conscientious, Agreeableness, and Openness.


 * Other personality tests include the NEO PI-R, Forté Profile, Millon Clinical Multiaxial Inventory, Eysenck Personality Questionnaire, Swedish Universities Scales of Personality, and Enneagram of Personality.