Coaley, K. (2009): An Introduction to Psychological Assessment and Psychometrics. Sage.

Psychological testing is about individual differences and measuring differences between people.

Statistics, validity and reliability are the key when evaluating test techniques.

INTRO
Basic questions related to chapter 1:

• What are the basic principles behind psychological assessment?
• Who are the key figures in the history of psychological assessment?
• What are the core characteristics of (+ issues relating to) different approaches?
• What is the use of different approaches in different areas of applied psychology?
• Ways of classifying tests?

PSYCHOLOGICAL ASSESSMENT
A short history:

• 2000 BC – the Chinese use tests for job selection purposes
• 16th century – beginning focus on individualism + individual differences
• LOCKE (17th century) – emphasis on empiricism (true knowledge comes from experience)
• DARWIN (1870’s)– focus on the significance of individual characteristics and differences
• FECHNER, WUNDT, EBBINGHAUS – experimental psychologists
• GALTON (1822-1911) – the importance of individual differences, ex mental ability tests, statistical analysis of data, the normal distribution, standard deviation, correlation etc.)
• BINET (1857-1911) – identifying which children were in need of special education, tests to identify children’s abilities at different ages, the Stanford-Binet Intelligence test.
• PEARSON (1857-1936) – regression analysis, correlation coefficient, chi-square test.
• THURSTONE (1887-1955) – techniques for measurement scales, assessment of attitudes, new methods of factor analysis.
• RASCH (1901-1980) – statistical models known as Rasch models, measuring attitudes on a continuum/scale.
• CATTELL (1905-1998) – contribution to the theoretical development of personality by applying empirical techniques to understand it’s basic structure.
• ANASTASI (1908-2001) – the ”test guru”, studies of cultural differences, test construction, test misuse, misinterpretation, cultural bias etc.
• KLINE (1937-1999) – explaining psychometrics, arguing in favour of truly scientific forms of measurement, transforming psychology into a pure science.

Først en interesse for individuelle forskelle, derefter udvikling af statistiske værktøjer (ex analyser af forholdet mellem individuelle karakteristika).

DIAGNOSTIC ASSESSMENT
Has a psychiatric background which is problematic due to unclear diagnostic categories and discussions concerning the concept of ”mental illness” ex Foucault who says that mental illness is a cultural construct.

A short history:
• Esquirol (18th C)
• Charcot (19th C)
• Freud (20th C)
• DSM-IV & ICD-10 (20th-21th C)

CORE CHARACTERISTICS OF ASSESSMENT
THE BASICS OF PSYCHOMETRICS:

STANDARDIZATION: ensuring the test is administered in the same way to all people and providing means of comparing test results (ex normative info on how different groups score on test).

RELIABILITY: the accuracy and consistency of scores.

VALIDITY: making sure you measure what you think and want to.

MEASURING/ASSESSING BY INFERENCE

How do you measure an abstract concept?

THE PROBLEM/QUESTION OF VALIDITY

How do you know what you are measuring?

”Evidence of validity provides a justification of the inferences you can make from an assessment”

TYPES OF MEASUREMENT

2 kinds of test:
• Maximum performance (ex speed, power, intelligence)
• Typical performance (ex personality, beliefs, interests)

Different ways of classifying assessment:
– Maximum performance or typical performance
– Standardized or non-standardized
– Individual administration or group administration
– Method of scoring responses (ex objective or subjective)
– Cognitive or affective

Quality criteria of psychological tests:
– Scope
– Reliability
– Validity
– Acceptability
– Practicality
– Fairness
– Utility

Uses of psychological tests:
– Research
– Practical
– Diagnosis
– Assessing change in response to therapy/treatment