Personality Psychology: LOTS of Data

The Scientific Study of People

The Data of Personality Psychology

• "LOTS" of data consists of L-data, O-data, T-data, and S-data
• L-data is information obtained from a person's life history or record.
• O-data is information provided by knowledgeable observers such as parents, friends, or teachers.
• Observers may be trained to observe systematically, and observations can be of very specific behavior or more general ratings of behavior.
• T-data is information obtained from experimental procedures or standardized tests.
• The objective is for answers to reveal something about the individual.
• S-data is information provided by the subject, typically in the form of responses to questionnaires.
• Limitations of self-reports include that people may be unaware of their psychological characteristics or motivated to present themselves positively.
• Advantages of self-reports are that they are convenient and easy to obtain.
• Researchers can combine data sources, thereby increasing confidence in research findings.
• New measurement types have developed as the field of personality psychology has progressed, and certain data forms do not easily fit into the four-category LOTS scheme
• Implicit individual-differences measures
• Diary methods

Contemporary Developments in Personality Research

• Focus on social media and language-based assessments, aided by computerized text analysis methods
• Software that can identify and count the frequency of linguistic features of interest to a researcher.
• These features can then be related to outcomes of interest.
• Can be combined with computerized text analysis to assess personality characteristics in huge populations.

How Data From Different Sources Relate to One Another

• Numerous factors influence the degree to which L, O, T, and S data sources agree with one another.
• S-data and T-data are often discrepant and feature broad judgments vs specific contexts
• Agreement between S-data and O-data is affected by self-perception biases, the relative observability of personality characteristics, and the ease with which a person can be judged.

Self-report Questionnaires

• Advantages of self-report questionnaires are that people know a lot about themselves
• Disadvantages include that people's self-descriptions can be influenced by phrasing and order of items, and people may lie or unconsciously distort their responses.
• Objective measures of behavior and the biological systems that underlie it may be more reliable.

Fixed vs Flexible Measures

• Fixed measures involve administering the same measures to all participants in a study and computing scores in the same way.
• It’s the commonly employed method in personality psychology as it’s objective and simple.
• Two potential limitations include some items may be irrelevant or there may be features of the personality that are not on the test.
• Flexible measures involve unstructured personality tests that allow people to describe themselves with their own words.
• Examples include asking people to list words or phrases that describe important aspects of their personality, or tell stories that relate their memories of important life experiences
• Fixed measures are also referred to as nomothetic measures, which describe a population of persons terms of a fixed set of personality variables.
• They come from the Greek for "law," nomos
• Flexible measures are also referred to as idiographic assessment techniques that are tailored to the particular individual beings studied
• They come from the Greek idios, referring to personal, private, and distinct characteristics
• Have the primary goal of obtaining a portrait of the potentially unique, idiosyncratic individual

Personality and Brain Data

• Personality psychologists want to identify biological mechanisms that contribute to personality
• Valuable types of evidence about brain functioning are electroencephalography (EEG) and fMRI.
• EEG uses electrodes placed on the scalp to record electrical activity of neurons.
• Electrodes are most sensitive to brain activity in regions of the brain closest to them.
• Researchers can determine which areas of the brain are most active at any given time.
• By simultaneously monitoring participants' psychological state and EEG activity, researchers can relate psychological activity to brain activity
• fMRI is a method for "imaging" brain activity while a person carries out different tasks.
• Blood flow to areas fluctuates as they become active during task performance.
• fMRI technology detects variations in blood flow and produces a picture of the brain that shows the regions that contributed directly to the task being performed.

Personality Theory and Assessment

• Personality assessment is any standardized procedure for learning about an individual's personality or for measuring differences among people in a population.
• They yield the basic data that psychologists use to accomplish their main professional goals, such as predicting people's behavior, conducting experimental research, understanding psychological problems, and formulating therapy strategies.
• Theory guides the assessment technique, and the choice of assessment target dictates the source of data one pursues.
• Assessment targets include average behavior, variability in behavior, conscious thought, and unconscious mental events
• Theoretical views determine thoughts about different measurement procedures.
• It is impossible to study personality by first collecting data and then creating a theory
• One needs a theory to decide what type of data is valuable and to interpret the data.

Goals of Research

• Reliability is the extent to which observations can be replicated and whether measures are dependable or stable.
• Factors affecting reliability include the psychological state of people being observed, aspects of the test, carelessness in scoring a test, and ambiguous rules for interpreting scores.
• Internal consistency is whether different items on a test correlate with one another if each reflects a common psychological construct.
• Test-retest reliability is if people take the test at two different times, do their scores correlate with one another?
• Validity is the extent to which observations actually reflect the phenomenon of interest in a given study.
• A test with discriminant validity will be empirically distinct from other tests that already exist.
• Reliability is necessary for validity
• The American Psychological Association (APA) has adopted a list of relevant ethical principles for research and public policy.
• The principles include the treatment of participants, interpretation and presentation of results, and reduction of personal and social bias.
• Personality tests are often used as part of employment, promotion, or admissions decisions.
• Research findings have also influenced government policy, including immigration policy, early enrichment programs such as Head Start, and television violence.

Three General Approaches to Research

• Case studies involve in-depth analyses of indvidual cases, where psychologists try to develop an understanding of the structures and processes that are most important to that individual's personality
• An inherently idiographic approach that may be conducted for research or treatment
• Personality tests and questionnaires are used where the intensive study of individuals is not possible or desirable.
• May also used when it is not possible to conduct laboratory experiments.
• Usually associated with the study of individual differences and how these variables go together, in correlational research
• Correlation coefficient is a statistic used to gauge the degree to which two variables and measures are linearly related.
• It is positive when people who have higher scores on one variable also have higher scores on another variable.
• It is negative when people who have higher scores on one variable also have lower scores on another variable.
• Variables with no systematic linear manner are uncorrelated.
• The value ranges from 1.0 (perfect positive) to -1.0 (perfect negative) Correlational research examines relations among variables in a large population of people without experimental manipulation.
• "Nun study" example shows the researchers asking nuns to write autobiographies, coding the autobiographies for amount of positive emotions expressed, then revealed a correlation between emotional experience and life
• Controlled experiments involve randomly assigning participants to an experimental condition and manipulating one or more variables.
• If people in one condition respond differently, then the variable that was manipulated causally influenced their responses.
• Claude Steele's work on "stereotype threat" shows that the stereotype may be confirmed, or interfere with one's performance if an individual is a member of a group for which there is a stereotype, and if the individual thinks of the stereotype. Steele examined performance of African-American and European-American college students on verbal test items that might be included on an intelligence test.
• There is a stereotype about intelligence about African-Americans.
• Black and white students randomly assigned to one of two conditions: demographic questionnaire vs no questionnaire
• Results showed that completing the demographic questionnaire lowered the test performance of black students

Evaluating Alternative Research Approaches

Special problems are associated with verbal reports

• People may distort things for unconscious reasons
• People may not have access to their internal processes
• When using verbal reports, must insist on evidence that: the same observations and interpretations can be made by other investigators i.e. reliable, the data do reflect the concepts they are presumed to measure. i.e. valid

Personality Theory and Personality Research

Theory and research inherently intertwined for 2 reasons:

• Theoretical conceptions suggest avenues for exploration and specify the types of data that qualify as evidence about personality
• Theorists have preferences and biases concerning how research should be conducted

Personality Assessment

• Assessment refers to two efforts: to measure personality aspects of individuals in order to make applied or practical decisions
• Will this person be a reasonable employee? Will this person profit from a kind of treatment?
• To arrive at a comprehensive understanding of individuals by obtaining a wide variety of information about them. No such test can give a picture of the total personality of an individual

Explore the types of data used in personality psychology: L-data (life records), O-data (observer reports), T-data (test data), and S-data (self-reports). Understand the advantages and limitations of each data source, and how researchers combine them for comprehensive insights into an individual's personality.