Trait Approaches and Psychometric Validation

Individual Differences and Assessment

  • Behavioral approaches (Skinner, Dollard, and Miller).
  • Social cognitive approaches (Bandura, Mischel).
  • Assessment methods:
    • Observation (self/others).
    • Questionnaires.
    • Test-retest reliability.
    • Item-total reliability.

Psychosocial Problem Conceptualization

  • Challenge: Comparing two measures of social anxiety.
  • Application: Measurement of key constructs.
  • Key psychometric notions:
    • Item-total correlations.
    • Test-retest reliability.
    • Construct validity.
    • Diaries.

Cognitive Behavioral (CB) Approaches

  • Finishing off CB approaches.
  • Trait approaches (Cattell, Eysenck).
  • Assessment:
    • Questionnaires.
    • Item-total reliability.
    • Intra-class correlations.
    • Factor structure.
    • Interpreting fit.
    • Criterion validity.

Cognitive Behavioral Theory

  • Expand on “hot cognitions” (Mischel’s Cognitive Affective Unit).
  • Draw on earlier social cognitive theorists like Bandura and Ellis.
  • Core beliefs:
    • Drive behavior.
    • Are deeply held and resistant to change.

Albert Ellis and Rational Emotive Therapy

  • A focused form of social cognitive theory.
  • Specific beliefs that drive mood/behavior:
    • Demandingness:
      • ”I have to be viewed favorably by people that matter to me.”
      • ”I must not be dismissed by my peers.”
    • Awfulizing:
      • ”It's awful if others do not approve of me.”
      • ”It's terrible if my team doesn’t respect me.”
    • Low-frustration tolerance:
      • ”I can’t tolerate failing.”
      • ”I can’t bear not getting better at what I do.”
    • Depreciation:
      • ”If others think I am no good at what I do, I am worthless.”
      • ”I am a loser if I do not succeed at things that matter to me.”

Common Core Beliefs About Self

  • Unlovability: Something wrong with me.
  • Helplessness:
    • Being ineffective in getting things done (I am incompetent).
    • Vulnerability (I am likely to get hurt).
    • Ineffective compared to other people (I am inferior, I can’t achieve like others).
  • Worthlessness:
    • I am a bad immoral sinner.
    • I am toxic bad person.
  • Negative beliefs about the world:
    • Other people are dangerous, don’t care.

Construct Validity

  • At least 5 types of construct validity:
    • Concurrent validity: New measure correlates well with previously established similar measure, administered at the same time.
    • Convergent validity: New measure correlates well with another measure of a theoretically related construct, administered at the same time.
    • Criterion-related validity: Predicting group membership or a real-world category.
    • Predictive validity: Does the measure predict something in the future that you would expect it to predict?
    • Divergent validity: A new measure correlates poorly with unrelated constructs.

Standard Deviation (SD)

  • A measure of dispersion – the average distance from the mean.
  • Is it good to have a SD that is much bigger than the mean?
  • Is it good to have a really small SD?

Trait Approaches

  • How relevant are they for understanding individual differences?
  • Not a great fit (in my view).
  • Keep pushing forward with psychometric analyses of measures, using trait theory and measurement tools as an example.
  • How to evaluate a measurement tool – factor structure.

Trait Theories Overview

  • Person-centered versus situationism.
  • They tend not to do well at accounting for development.
  • A focus on the present.
  • Consistent across time.
  • Consistent across context.
  • Low emphasis on mechanisms.
  • Not concerned with “why” or “how” personality changes.
  • Primarily concerned with description, organisation and prediction

Raymond Cattell

  • Personality is that which permits a prediction of what a person will do in a given situation.
  • Desirable/undesirable, normal/abnormal is irrelevant.
  • Rigorous scientific approach: SCIENCE DEMANDS MEASUREMENT!
  • Distinguishing feature: FACTOR ANALYSIS.
  • 16PF.

Factor Analysis

  • A data grouping and data reduction technique.
  • Based on the logic of the correlation coefficient.
  • Trait theory a good subject to explore with factor analysis.
  • A nice paper – easy to read if you are new to it. Williams, Onsman & Brown 2010 (QUT Readings Week 4)
  • Aims:
    • Reduce number of vars – principle of parsimony.
    • Examine the structure of your questionnaire.
    • Detect whether unidimensional or multidimensional.
    • Evaluate construct validity.
    • Can look for multicollinearity.
    • Can use to develop/refine theoretical constructs.
  • Sample size – hugely variable 1:20 or higher is typical.
  • What type of factor extraction?
    • Principal components analysis (PCA).
    • Principal axis factoring.
    • Maximum likelihood.

How to Decide on Number of Factors

  • A few methods.
    • In CFAs you can propose a certain number – force the model to fit 1 or more factors.
    • In EFAs it is often less clear.
  • In general, don’t rely on one method.
  • Eigenvalues great than 1.
  • The Scree Test.
  • Can look at how much variance each solution adds.
  • Eigenvalues - this value tells you how much variance is explained by a group of items. Each eigenvalue will be greater than 1, but usually factors close to one don’t account for much variance (this approach is overinclusive).
  • Extraction loadings – each factor starting with the biggest eigenvalue will add a certain amount of variance (‘cumulative %’) – gets smaller and smaller as you go along… usually stop increasing factors when cumulative % gets really small.
  • A plot of the factor/principal component ordered by eigenvalue size – look for change in direction of lines of best fit.
  • Variance - a measure of dispersion – the average of squared deviations around a mean.

Hans Eysenck

  • Eysenck Personality Inventory.
  • Concise model: 3 dimensions, or superfactors…
  • Thought that Cattell’s 16 personality factors were unreliable.
  • Personality largely governed by biology and shaped in childhood.

The Superfactors

  • Extraversion versus introversion (E).
  • Neuroticism versus emotional stability (N).
  • Psychoticism versus impulse control (P).
Extraversion
  • Oriented toward outside world.
  • Prefer company.
  • Highly sociable, impulsive, assertive, dominant and adventurous.
Neuroticism
  • Anxious, depressed, tense, irrational, moody.
  • Largely inherited.
  • More activity in sympathetic branch of the ANS (bodies alarm system).
  • Hypersensitivity and emotionality.
Psychoticism
  • Aggressive, antisocial, tough-minded, cold egocentric versus impulse control (warmth and empathy).
  • Can be cruel, hostile, insensitive.
  • Large genetic component.

Traits/Facets (Costa & McCrae)

  • Developed the NEO Personality Inventory – Revised, which included some elements of Eysenck’s model but included two more..
  • Each dimension based on an extreme (e.g., extraversion – introversion), each person falling somewhere on the continuum.

Gignac

  • Gignac – ‘partial confirmatory factor analysis’.
  • Something in between an EFA and a CFA.
  • Used when know the number of factors, but don’t know what the loadings are…

Factor Analysis Continued

  • Identification of “factors”.
  • Factor - cluster of related behaviour measures.
  • Factor loading - extent to which each measure is related to each factor.
  • Items with high loadings go together.
  • Ideally factors should be minimally correlated.

Factor Naming

  • Factors are named based on semantic consistency.
  • Identification of factors is empirical, naming of factors is rather subjective

Exploratory versus Confirmatory Factor Analysis (EFA vs CFA)

EFA

  • An unrestricted FA.
  • All latent constructs are correlated with all items.
  • Focus is on establishing an underlying factor structure.
  • Used for scale development, on items that haven’t been tested much

CFA

  • Used to verify a factor structure.
  • Based on theoretical reasons and/or past empirical research
  • Hypothesis a structure and test how the data fit with that structure.

Second Order FA

  • One could do a factor analysis that has two levels….
    • Neuroticism: Anxiety, Hostility, Depression, Self- consciousness, Impulsiveness, Vulnerability.
    • Extroversion: Warmth, Gregariousness, Assertiveness, Activity, Excitement-Seeking, Positive Emotions.
    • Openness to Experience: Fantasy, Aesthetics, Feelings, Actions, Ideas, Values.
    • Agreeableness: Trust, Straightforwardness, Altruism, Compliance, Modesty, Tender- mindedness.
    • Conscientiousness: Awareness of actions and consequences: Competence, Order, Dutifulness, Achievement Striving, Self-Discipline, Deliberation.

How Well Does a Model Fit?

  • Lots of indices to test how well the proposed model accounts for the correlation of all items.
    • Chi-square – want small numbers, generally less than 3.
    • Fit of the model – don’t want a significant difference (>.05).
    • Comparative Fit index (CFI).
    • Analysis the discrepancy between the data and hypothesised model, while adjusting for sample size.
    • CFI > .90 acceptable.
    • Standardised root mean square residual (SRMR).
    • Fit of observed correlation matrix and the predicted correlation – positive biased when sample sizes are small.
    • want small as possible, generally less than 0.09.

RMSEA

  • Root mean square error of approximation (RMSEA).
  • A sophisticated fit index tests how far a hypothesised model is from a perfectly fitting model.
  • Smaller RMSEA, the better (ideally less than 0.08 for ‘good fit’)’.
  • Assessing fit.
  • Do not rely on a single measure.
  • Look at the pattern of fit across several indices (it is not necessarily bad to have one of several indices that suggests the model doesn’t fit).

Etzler & Rohrmann (2017)

  • Development and preliminary validation of a brief questionnaire of psychopathic personality traits’.
  • Measuring psychopathology via self-report.
  • Psychopathic Personality Inventory (PPI) is well validated, but has 154 items and inconsistent factor analysis, 45-50 minutes.
  • This study: Develops the Questionnaire of Psychopathic Personality Traits.

Key Aims of the Paper

  • Evaluated whether:
    • the measure correlates with other established measures (focus on how correlates with another measure called the PPI) – Kind of construct validity?
    • The scale correlates with an external ‘gold standard’ criterion, such as criminal charges? - Kind of construct validity?
    • Does the scale have factorial invariance (i.e., do the psychometric properties stay the same across different groups?) - Kind of construct validity??? (more debate here – what do you think?)

Statistical Analyses

  • Missing data for the FPP was 2.5%.
  • Following Hu and Bentler (1999), model fit was considered acceptable if x2/df<2x^2/df <2, RMSEA<0.06RMSEA < 0.06, SRMR<0.08SRMR < 0.08, and CFI>0.95CFI > 0.95. Factor loadings of 0.300 were considered as acceptable.

FPP Constructs

  • Lack of empathy, fearlessness, narcissistic egocentrism, impulsivity, social manipulation, power, fearlessness.
  • Second order trait ‘Psychopathology’.

Week 4 Summary

  • Factor analysis (EFA vs CFA).
  • What a FA can tell you about your tool:
    • Does it measure what you want it to measure?
    • How clear and distinct are the factors?
  • How to read a table of factors.
  • How to decide on the number of factors.
  • How to interpret fit.