CSS Psychology Psychological Assessment and Individual Differences Syllabus

What is item-total correlation and what does it indicate?

It is the correlation between performance on a single item and the total test score. A high positive correlation indicates the item measures the same construct as the test as a whole; low/negative values flag poor items.

What are norms in psychological testing?

Norms are summary statistics (e.g., means, percentiles, standard scores) derived from a representative standardization sample, providing a framework to interpret an individual's score relative to a defined reference group.

Differentiate norm-referenced from criterion-referenced testing.

Norm-referenced interpretation compares an individual's score to a norm group's performance (relative standing). Criterion-referenced interpretation compares a score to a fixed standard or mastery level (absolute performance).

What are percentile ranks?

A percentile rank indicates the percentage of people in the norm group who scored at or below a given raw score. For example, a percentile rank of 80 means the person scored as well as or better than 80% of the reference group.

What are standard scores (z-scores) and how are they computed?

A z-score expresses a raw score in terms of standard deviations from the mean: z = (X − M) / SD. It has a mean of 0 and SD of 1, allowing comparison across different tests.

What are T-scores and how do they relate to z-scores?

T-scores are standardized scores with a mean of 50 and a standard deviation of 10. Conversion: T = 50 + 10z. They avoid negative values and decimals common with z-scores; widely used in personality tests like the MMPI.

What distinguishes Modern Test Theory (Item Response Theory) from Classical Test Theory?

IRT models the probability of a response as a function of a person's latent trait (ability) and item parameters, yielding sample-independent item statistics and person-independent ability estimates. CTT statistics are sample-dependent and test-dependent.

Name the three item parameters in IRT models.

a = discrimination (slope of the item characteristic curve), b = difficulty (trait level at 50% probability of correct response), and c = guessing (lower asymptote/pseudo-chance). 1PL uses b; 2PL uses a and b; 3PL adds c.

What is an Item Characteristic Curve (ICC) in IRT?

An ICC is an S-shaped (logistic) curve plotting the probability of a correct/endorsed response against the latent trait level (theta). Its shape is defined by the item's difficulty, discrimination, and guessing parameters.

What is the Rasch model?

The Rasch (1PL) model is an IRT model in which the probability of a correct response depends only on item difficulty (b) and person ability, assuming equal discrimination across items. It places persons and items on the same logit scale.

What is Computerized Adaptive Testing (CAT) and on what theory is it based?

CAT is a test format, based on IRT, where the difficulty of each successive item is tailored to the test-taker's estimated ability from prior responses, producing efficient, precise measurement with fewer items.

What is the purpose of personnel selection in industrial-organizational psychology?

To choose, from a pool of applicants, the individuals most likely to perform successfully, using job analysis to identify required KSAOs and valid predictors (tests, interviews, work samples) to forecast job performance.

What is a job analysis and why is it foundational to selection and training?

A job analysis is a systematic procedure to identify the tasks, duties, and the knowledge, skills, abilities, and other characteristics (KSAOs) required for a job. It is the basis for content-valid selection tools, training design, and performance criteria.

Define base rate, selection ratio, and incremental validity in selection.

Base rate = proportion of applicants who would succeed without the test. Selection ratio = number hired / number of applicants. Incremental validity = the added predictive value a new predictor contributes beyond existing ones (often shown via Taylor-Russell tables).

Distinguish formative from summative evaluation in educational assessment.

Formative evaluation occurs during instruction to monitor progress and guide improvement (low stakes, ongoing). Summative evaluation occurs at the end to judge overall achievement or assign grades (high stakes, terminal).

What is achievement testing versus aptitude testing?

Achievement tests measure knowledge/skills already acquired through learning (past learning). Aptitude tests measure potential to learn or perform in the future (predicting future performance).

What is a clinical interview and what are its main types?

A clinical interview is a directed conversation to gather information for diagnosis/treatment. Types include unstructured (flexible), structured (fixed questions, e.g., SCID), and semi-structured (mix), as well as intake, mental status, and diagnostic interviews.

What is the Mental Status Examination (MSE)?

The MSE is a structured clinical assessment of a patient's current psychological functioning, covering appearance, behavior, mood/affect, speech, thought process and content, perception, cognition, insight, and judgment.

What is the difference between clinical and statistical (actuarial) prediction?

Clinical prediction relies on a clinician's subjective judgment to integrate data. Statistical/actuarial prediction uses empirically derived formulas/algorithms. Research (Meehl) generally shows actuarial prediction equals or outperforms clinical judgment.

What is informed consent in psychological assessment?

Informed consent is the ethical requirement that test-takers (or guardians) be told the nature, purpose, procedures, risks, benefits, and intended use of an assessment, and voluntarily agree before testing, with the right to refuse or withdraw.

What are the key ethical responsibilities regarding test confidentiality and security?

Practitioners must keep test results confidential (releasing only to authorized parties), protect test materials and items from public disclosure, and ensure competent, fair use of tests to prevent misuse or harm.

What is test bias and how does it differ from test fairness?

Test bias is a systematic statistical/psychometric error causing a test to measure differently across groups (e.g., differential validity or item functioning). Fairness is a broader value-based judgment about equitable use and consequences of test scores.

What is Differential Item Functioning (DIF)?

DIF occurs when individuals from different groups (e.g., gender, ethnicity) but with the same underlying ability level have different probabilities of answering an item correctly, indicating potential item bias.

What are the main determinants of personality?

The major determinants are biological/hereditary factors (genetics, physiology, temperament), environmental factors (culture, family, socialization), and situational factors. Personality is generally seen as a product of nature-nurture interaction.

List key factors in the development of personality.

Heredity/biological factors, family/parenting and early childhood experiences, culture and social class, peer groups and school, gender roles, birth order, and significant life experiences all shape personality development.

What does the psychoanalytic (Freudian) perspective propose about personality structure?

Freud proposed three structures: the Id (unconscious, pleasure principle), the Ego (reality principle, mediator), and the Superego (morality/conscience). Personality is driven by unconscious conflicts and early psychosexual development.

Summarize the Big Five (OCEAN) trait model of personality.

The five-factor model: Openness to experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism. These broad dimensions are the dominant trait taxonomy, often assessed by the NEO-PI-R.

Contrast the humanistic perspective with the behaviorist perspective on personality.

Humanistic (Maslow, Rogers) emphasizes free will, self-actualization, and subjective experience, viewing people as inherently growth-oriented. Behaviorist (Skinner) emphasizes observable behavior shaped by environmental conditioning, rejecting internal traits as causes.

Differentiate projective from objective (self-report) personality tests, with examples.

Projective tests present ambiguous stimuli to elicit unconscious material (e.g., Rorschach Inkblot, TAT); they are low in structure and rely on interpretation. Objective tests use structured, scorable items (e.g., MMPI, NEO-PI-R, 16PF) and are more reliable and standardized.

What is the MMPI and what is it primarily used for?

The Minnesota Multiphasic Personality Inventory is a widely used objective self-report inventory assessing psychopathology and personality structure. It uses empirically derived clinical scales plus validity scales (L, F, K) to detect response distortion.