Personality Psychology - Chapter 2

Self-Report Data (S-Data)

The information a person reveals. Can be obtained through a variety of means, including interviews that pose questions to a person.

Good reasons for using: individuals have access to a wealth of information about themselves

Limitations: People are not always honest, some may lack accurate self-knowledge

Unstructured

Open ended self report data, such as "tell me about the parties you like the most"

Structured

Not open ended self report data (True or False, you like large parties)

Likert rating scale

Involves requesting participants to indicated in numerical form the degree to which each trait term characterizes them, on a scale of 1(least) to like, 7 (most. A way to express with numbers the degree to which a particular trait describes him or her

Personality scale

consists of summing the scores on a series of individual rating scales

Experience sampling

In this method, people answer some questions, perhaps about their moods or physical symptoms, every day for weeks or longer.People are usually contact electronically one or more times a day at random intervals to complete the measures.

Observer Report Data (O-Data)

Friends, families, teachers, and casual acquaintances are all potential sources of information about personalities. O-data capitalize on these sources for gathering information about a person's personality.

Advantages: observers may have access to information not attainable through other sources, multiple observers can be used to assess each individual, which allows investigators to evaluate the degree of inter-rater reliability.

Inter-rater reliability

The degree of agreement among obsercers

multiple social personalities

Each of us displays different sides of ourselves to different people -- we may be kind to our friends, ruthless to our enemies, loving toward a spouse, and conflicted toward our parents. The use of multiple observers provides a method for assessing the many aspects of an individual's personality.

Naturalistic observation

observers witness and record events that occur in the normal course of the lives of their participants

Test data (T-data)

Personality-relevant information obtained from standardized tests

Physiological measurement

Critical source of personality data that can provide information about a person's level of arousal, a person's reactivity to various stimuli, and the speed at which a person takes in new information -- all potential indicators of personality.

functional magnetic resonance imaging (fMRI)

A technique used to identify the areas of the brain that "light up" when performing certain tasks such as verbal problems or spatial navigation problems. It works by gauging the amount of oxygen that is brought to particular places in the brain. When a certain part of the brain is highly activated, it draws large amounts of blood. The oxygen carried by the blood accumulates in that region of the brain. The fMRI is able to detect concentrations of iron carried by the oxygen contained in the red blood cells and thus determine the part of the brain that is used in performing certain tasks.

Projective techniques

Another type of T-data in which the person is given a standard stimulus and asked what he or she sees. Example: inkblots, making up a story for a picture

Life-outcome data (L-data)

Refers to information that can be gleaned from the events, activities, and outcomes in a person's life that are available to public scrutiny.

Reliability

Can be defined as the degree to which an obtained measure represents the true level of the trait being measured.

Ways to gauge reliability

1) Repeated measurement (test-retest reliability)

2) Examining the relationships among the items themselves at a single point in time. (internal consistency reliability)

3) Obtain measurements from multiple observers (inter-rater reliability)

repeated measurement (test-retest reliability)

A way to estimate reliability -- there are different forms of repeated measurement. A common procedure is to repeat a measurement over time -- for example, at intervals of one month -- for the same sample of persons. If the two tests are highly correlated, yielding similar scores for most people, the resulting measure is said to have high "test-retest reliability."

Internal consistency reliability

Examine the relationships among the items themselves at a single point in time. If the items within a test -- viewed as a form of repeated measurement, all correlate well with each other, then the scale is said to have "internal consistency reliability." The reliability is internal because it is assessed within the test itself.

Inter-rater reliability

Applicable only to the use of observer-based personality measures -- to measure this, it is necessary to obtain measurements from multiple observers. When different observers agree with each other, the measure is said to have high "inter-rate reliability."

Response sets

Refers to the tendency of some people to respond to the questions on a basis that is unrelated to the question content. Can also be called noncontent responding.

Acquiescence

Saying yes. This is the tendency to simply agree with the questionnaire items, regardless of the content of those items. Psychologists counteract acquiescence by intentionally reverse-scoring some of the questionnaire items, such as an extraversion item that states, "I frequently prefer to be alone."

Extreme responding

Another response set, which refers to the tendency to give endpoint responses such as "strongly agree" or "strongly disagree" and to avoid the middle part of response scales, such as "slightly agree" or "slightly disagree."

Social desirability

A response set that has received the greatest amount of research and evaluation by personality psychologists. Socially desirable responding is the tendency to answer items in such a way as to come across as socially attractive or likable. People responding in this manner want to make a good impression, to appear to be well-adjusted, to be good citizens.

Two views regarding the interpretation of social desirability

1) That it represents distortion or error and should be eliminated or minimized

2) That social desirability is a valid part of other desirable personality traits, such as happiness, conscientiousness, or agreeableness.

Forced choice questionnaire

In this format, test takers are confronted with pairs of statements and are asked to indicate which statement in each pair is more true of them. Each statement in the pair is selected to be similar to the other in social desirability, forcing participants to choose between statements that are equivalently socially desirable/undesirable, meaning they should respond to the content of the item and provide accurate information about their personalities.

Validity

Refers to the extent to which a test measures what it claims to measure.

5 Types of Validity

1) Face validity

2) Predictive validity

3) Convergent validity

4) Discriminant validity

5) Construct validity

Face validity

Refers to whether the test, on the surface, appears to measure what it is supposed to measure.

Predictive validity (criterion validity)

Refers to whether the test predicts criteria external to the test. For example. a scale measuring conscientiousness should predict which people actually show up on time for meetings and follow rules.

Convergent validity

Refers to whether a test correlates with other measures that it should correlate with. For example. if a self-report measure of tolerance corresponds well with peer judgments of tolerance, then the scale is said to have high convergent validity.

Discriminant validity

Often evaluated simultaneously with convergent validity. Whereas convergent validity refers to what a measure should correlate with, discriminant validity refers to what a measure should NOT correlate with. Part of knowing what a measure actually measures consists of knowing what it does not measure.

Construct validity

Defined as a test that measures what it claims to measure, correlates with what it is supposed to correlate with, and does not correlate with what it is not supposed to correlate with. Thus, this is the broadest type of validity, subsuming the other four kinds. It is called construct validity because it is based on the notion that personality variables are theoretical constructs. Determining whether actual measures can claim to be valid ways of assessing the constructs is the essence of construct validity.

Generalizability

The degree to which the measure retains its validity across various contexts or conditions. Contexts can include groups of people (demographics). Conditions can include informal, professional, etc.

Three basic research designs in the field of personality psychology:

-Experimental

-Correlational

-Case study

Experimental methods

Typically used to determine causality -- to find out whether one variable influences another. In order to establish the influence of one variable on other, two key requirements of good experimental design must be met.

1) Manipulation of one or more variables

2) Ensuring that participants in each experimental condition are equivalent to each other at the beginning of the study.

Manipulation

In manipulation, the variable thought to be the influence is manipulated as part of the experiment.

Random assignment

Assignment in an experiment that is conducted randomly. If an experiment has manipulation between groups, random assignment of participants to experimental groups helps ensure that each group is equivalent.

Counterbalancing

In some experiments, manipulation is within a single group. For example. participants might get a drug and have their memory tested, then later take a sugar pill and have their memory tested again. In this kind of experiment, equivalence is obtained by counterbalancing the order of the conditions, with half the participants getting the drug first and sugar pill second, and the other half getting the sugar pill first and drug second.

Statistically significant

p <.05

Correlational method

A statistical procedure is used for determining whether or not there is a relationship between two variables. In correlational research designs, the researcher is attempting to identify directly the relationships between two or more variables, without imposing the sorts of manipulations seen in experimental designs.

Correlation coefficient

The most common statistical procedure for gauging relationships between variables.

Two correlations that cannot prove causality.

1) Directionality problem

2) Third variable problem

Directionality problem

If A and B are correlated, we do not know if A is the cause of B or if B is the cause of A.

Third variable problem

Two variables might be correlated because a third, unknown variable is causing both.

Case study method

Examining the life of one person in-depth. Researchers can find out personality in great detail, which rarely can happen if the study includes a large number of people. Can be useful in studying particularly outstanding individuals as well as rare phenomena such as someone with photographic memory or multiple personalities.