History of Psychometrics
History of Psychometrics: Chinese Influence
From ~2000 BCE to the early 1900s, such testing practices existed but were later discontinued
These tests included systematically testing intelligence, ability, knowledge, aptitude
2000 B.C.E.
Scattered evidence of civil service testing in China
206 B.C.E. to 220 C.E.
Han Dynasty in China develops test batteries
Two or more tests used in conjunction
Test topics included civil law, military affairs, agriculture, revenue, geography
Scores from these tests determined which jobs people could do
Select government workers
Started putting more weight onto these tests:
1368 C.E. to 1644 C.E.
Ming Dynasty in China develops multistage testing
Local tests lead to provincial capital tests, capital tests lead to national capital tests
Only those that passed the national tests were eligible for public office
1832 → English East India Company (based in UK) copies Chinese system to select employees for overseas duty
Up until this point, these tests were used to allocate people to jobs
Used scores at face value, as it were objectively correct, to put people to jobs
1855 → British Government adopts English East India Company selection examinations
French and German gov follow shortly
1883 → US establishes the American Civil Service Commission
Developed and administered competitive examinations for government jobs
History of Psychometrics: Individual Differences, Darwin and Galton
Darwin: Individual differences– despite our similarities, no two humans are exactly alike → because some individual differences are more ‘adaptive’ than others
These differences, over time, lead to more complex, intelligent organisms
This was formally published in 1859
Galton → introduced the idea that psychological traits can be measured, created the first systematic mental tests
Galton (Darwin’s cousin): some people possessed characteristics that made them ‘more fit’ than others
First systematic mental tests in 1884 London → Anthropometric Lab → looked at the variation between human responses, how did ppl do things differently based on who they were, what were the different range of responses they could get from people
Lab involved playing sounds from a whistle to measure range of sounds people could hear, or have people estimate a bar’s length
This established the tradition of individual differences testing, which modern psychometrics is built on
Galton also noted that persons with mental retardation (delay/hindrance) also tend to have diminished ability to discriminate among heat, cold, and pain
Other advances of Galton’s:
Considered by some the founder of psychometrics → measured ppl’s reactions, abilities, reactions
Pioneered rating scales and questionnaires
First to document individuality of fingerprints → first to notice the difference in ppl’s fingerprints
Studied efficacy of prayer
First to apply statistics in the measurement of humans
Founder of eugenics
Eugenics: let the fittest survive; don’t treat or help people that actually have bad genes or traits (let them die) so that these traits are not around anymore, it ‘purifies/cleanses’ the population
So like, not letting the bad genes to be reproduced
History of Psychometrics: Galton’s Famous Students
Karl Pearson: extended Galton’s early work with statistical regression
Developed:
Linear regression as a formal statistical method
Product-moment correlation (1896)→ we now call it Pearson’s r/ Pearson correlation coefficient
Standard deviation and variance as measures of spread
The chi‑square test
James McKeen Cattell: first to use the term “mental test”
U.S. dissertation on reaction time based upon Galton’s work
History of Psychometrics: Early Experimental Psychologists
Early 19th century scientists, generally interested in identifying common aspects, rather than individual differences → what is the normal behaviour? (different from Galton’s)
Differences between individuals was considered a measurement of error from tools and could just be ignored. This is caused by instruments producing slightly different readings each time so scientists assumed that the true value is the average
Johan Friedrich Herbart: mathematical models of the mind; founder of pedagogy as an academic discipline; went against Kant’s theories
Ernst Heinrich Weber: sensory thresholds; ‘just noticeable differences’ (JND) → how much the things have to differ before you can tell that they are different
Gustav Theodor Fechner: mathematics of sensory thresholds of experience; founder of psychophysics; considered as a founder of experimental psychology; first to relate sensation and stimulus; considered by some the founder of psychometrics
He influenced many prominent psychologists, such as Wundt, Freud
Wilhelm Wundt: considered one of the founders of psychology; first to set up a psych laboratory
Edward Tichner: succeeded Wundt; brought Structuralism to America
Guy Montrose Whipple (student of Tichner’s): pioneer of human ability testing, conducted seminars that changed the field of psych testing, APA issued its first set of standards for professional psych testing because of his criticisms
He made psych testing more ethical because before his criticisms psych tests were used in wrong ways
Luis Leon Thurstone: large contributor to factor analysis, attended Whipple’s seminars, approach to measurement was termed the law of comparative judgement
History of Psychometrics: Interest in Mental Deficiency
1805 Jean-Étienne Esquirol, French Physician
Favourite student of Philippe Pinel (founder of psychiatry)
Wrote a manuscript on ‘mental retardation’
Differentiated between insanity and mental retardation
E.g. insanity had a period of normal intellectual functioning
Measured degrees to mental retardation
Normality to ‘low-grade idiocy’
Attempted to develop system to classify people into these many degrees but found that the individual’s use of language provided the most dependable continuum
1940s Edouard Seguin, French Physician
Pioneer in training mentally-retarded
Rejected the notion of incurably mental retard
1837: opens first school devoted to teach mentally retarded children
1848: emigrates to USA, wide acceptance of his theories
1866s: experiments with physiological training of mentally retarded people
Sense-training/muscle-training still used today
Leads to nonverbal tests of intelligence (Seguin Form Board)
History of Psychometrics: Intelligence testing
50 years after Esquirol and Seguin → 1905
Alfred Binet
French Society for the Psychological Study of the Child urged French ministers to develop special classes for children who failed to respond to normal schooling
Ministers required a way to identify the children for special education
First Intelligence Test: Binet-Simon Scale of 1905
30 items of increasing difficulty
Standardised administration → same instructions and format for ALL children
Standardisation sample → created norms by which performance of one child can be compared with other children
50 normal children aged 3-11 years, ‘some’ mentally retarded children and adults
They tried to standardise what was ‘normal’ by looking at this sample of 50 children
In 1908, more items were added for greater reliability
Better standardisation sample (300 normal children)
Introduction of Mental Age: the child’s standing among children of different chronological ages in terms of his or her cognitive capacity
Alfred Binet’s Legacy
1911 Binet-Simon minor revision
Binet dies
1912 Kulmann-Binet revision
Extends testing downward to 3 months of age
1916 Lewis Madison Terman and Stanford Colleagues revise Binet’s test for use in US
More psychometrically sound procedures (reliable, valid)
Intro of the term IQ
Mental Age/Chronological Age = IQ (intelligence quotient, see above images)
Terman was a Eugenicist
This is not good because the intelligence testing was used to identify and support children with learning needs but being a Eugenicist is opposite of this goal
So a Eugenist bringing the test to the US → funnel sources away from them?? Thats suspicious
But luckily it wasn’t being consistently, widely used like that, been used for both pos and neg purposes
Neg purposes → IQ score determined if you tried as an independent adult (e.g. if u murdered someone but ur IQ is below 70 u wouldn’t receive death sentence)
WW1
Robert Yerkes
Him and Colleagues developed two group tests of general mental ability for use with recruits to the US armed services during the First World War.
Army Alpha test assessed the ability levels of those who could read and write
Army Beta test for those who were not literate.
Although there is some dispute about how valuable the Army Alpha and Beta tests were to the war effort, they gave considerable impetus to psychological testing in the postwar period, and their basic structure was used subsequently by Wechsler when developing the Verbal and Performance subscales for his test of adult intelligence.
There was a testing frenzy in 1930s
1937 revision of the Standford-Binet includes over 3000 individuals in standardisation
1939 Wechsler-Bellevue Intelligence Scale
Developed by David Wechsler and was a rival of Standford-Binet
Subscales were adopted from the Army Scales
Produces several scores of intellectual ability rather than Binet’s single scores (e.g. Verbal, Performance, Full-Scale)
Didn’t really require reading, more performance focused
Evolves into the Wechsler Series of Intelligence tests (e.g. WAIS, WISC, etc.)
History of Psychometrics: Personality Testing
Rise 1920s, Fall 1930s, Slow Rise 1940s
Intended to measure personality traits (not temporary state)
Trait: relatively enduring dispositions (tendencies to act, think or feel in a certain manner in any given circumstance)
First Rise and Fall
WW1 Robert Woodworth
Woodworth Personal Data Sheet
First objective personality test meant to aid in psychiatric interviews
Designed to screen out soldiers unfit for duty
Problem: Mistakenly assumed that a subjects’ responses could be taken at face value (i.e. no faking)
Problem: wording questions and questions were questionable
Slow Rise: Projective Tests
Project your thoughts from an image
Herman Rorschach inkblot test (1921)
Started with great suspicion but was taken seriously in 1932
Systemetric colored and b/w inkblots
Your brain constantly makes sense of patterns, therefore these tests are trying to understand what you make sense of these nonsensical patterns
Based on Freud’s Fundamental assumption of psychic determinism- all mental events have a cause.
But responses may reflect cultural background rather than personality traits, reducing fairness and accuracy, interpretation depends heavily on the examiner’s training, theoretical orientation, and biases.
Thematic Apperception Test
1935 Henry Murray and Christiana Morgan
“Ambiguous” pictures, more structured than Rorschach
Subjects shown the picture and asked to write a story including:
What has led up to the event shown
What is happening at the moment
What the characters are feeling and thinking
What the outcome of the story was
Minnesota Multiphasic Personality Inventory (MMPI)
Early 1940s Starke R. Hathaway
Designed to discriminate between those without symptoms of mental illness (‘normal’) and patient groups with particular diagnosis.-566 Items.
Tried to deviate from tests like Woodworth where it made too many assumptions
The meaning of the test response could only be determined by empirical research
Most widely used (MMPI-2, MMPI-A)
At the same time, there was other personality questionnaires being developed
Sixteen Personality Factor Questionnaire
Early 1940s Raymond B. Cattell
Based on Factor Analysis → method for finding the minimum number of dimensions (factors) for explaining the largest number of variables