WIXLIB

Psychological Testing:IntroductionCal State NorthridgeΨ427Andrew Ainsworth PhDQuestions You’ll Encounter What is a psychological test? Are there different kinds of psych tests? For what purposes are the used? Have psych tests ever been used on me? How do we know if a test is reliable? Valid? Statistics AGAIN?Psy 427 - Cal State Northridge2Questions You’ll Encounter What are qualities of “good” test items? How can testing situations affect responses? What is an “IQ” anyway? Does IQ really measure intelligence? Should schools really care about my SAT?GRE? LSAT? MCAT?Psy 427 - Cal State Northridge31

Questions You’ll Encounter Can my reaction to some weird inkblot reallysay something about my personality?Can my response to a bunch of weird T/Fquestions really indicate that I have apsychopathology?All I want to do is help people, why do I needto submit them to all these torturous tests?Psy 427 - Cal State Northridge4Psychological Testing AKA Psychometrics – field of study concerned withthe theory and technique of educational andpsychological measurement (Wikipedia) measurement of knowledge, abilities, attitudes,and personality traits.It involves two major research tasks1.2.the construction of instruments and procedures formeasurementthe development and refinement of theoreticalapproaches to measurementPsy 427 - Cal State Northridge5Measurement In psychology we are interested ineither describing the distributions ofand/or relationships among abstractconcepts: e.g., Political conservatismIntelligenceNeuroticismAggressionPsy 427 - Cal State Northridge62

Measurement However, in most cases these constructs areabstractions that can often not be directly observed.Concept of IntelligenceOperationalizationMeasure or Operationalization of IntelligenceIQ testPsy 427 - Cal State Northridge7Measurement Note: that the degree to which theoperationalization of the abstract conceptactually reflects or mirrors the construct is thedegree to which the operationalization can besaid to be valid (more later).The value of scientific research is completelydependent upon the degree to which theoperationalizations are successful or valid.Psy 427 - Cal State Northridge8Concepts and Constructs Concept: “An abstraction formed by generalization fromparticulars”Abstracts are hard to defineE.g. intelligenceConstruct: A concept with scientific purpose (i.e.operationalized)Can be measured and studied.E.g. IQPsy 427 - Cal State Northridge93

Terms Review: Variables and Constants Variable: any condition, event, characteristicor attribute that can take on different valuesat different times or with different people. Age of peopleTemperatureIntelligenceXenophobiaConstant: One value in a given context.Does not change or vary.Psy 427 - Cal State Northridge10Terms Review:Independent and Dependent Variables Independent variable we are referring to a variable that theexperimenter has some direct control over andcan manipulateIn Experiments IVs are the “cause”In non-experiments IVs are the “influencei.e., X YDependent Variables The variable being influenced/predictedThe outcome variablePsy 427 - Cal State Northridge11Terms Review:Discrete & Continuous Variables Discrete variables: can only take on a finite orrestricted set of values. Continuous variables: can take an infinitenumber of values Can only take on whole values (think digital)E.g., number of children per family, Number ofstudents taking 100AE.g., Temperature (10.3 C, 10.24 C, 15.212 C),Weight (102.2lbs., 116.56 lbs.)The difference often limited only by precision124

Psych Testing Basics Test A measurement device or technique used toquantify behavior or aid in the understanding andprediction of behavior. Psychological Test a set of items designed to measure characteristicsof human beings that pertain to behavior.Behavior Overt: observable activity of the individualCovert: takes place within the individualPsy 427 - Cal State Northridge13Psych Testing Basics Scale Relate raw scores on a test to some definedtheoretical or empirical distribution.A method of operationalizing a psychologicalconstruct using a multiple item test (e.g.questionnaire)Psy 427 - Cal State Northridge14Types of Tests Individual Tests vs. Group Tests Individual tests: test administrator gives a testto a single person e.g. WAIS-III, MMPI-2Group tests: single examiner gives a test to agroup of people e.g. SAT, GREPsy 427 - Cal State Northridge155

Types of Tests (Human) Ability Tests Achievement Tests Aptitude Tests evaluates what an individual has learnedmeasures prior activityevaluates what an individual is capable of learningmeasures capacity or future potentialIntelligence Tests Measures a person’s general potential to solveproblems, adapt to novel situations and profit fromexperiencePsy 427 - Cal State Northridge16Types of Tests Personality Tests: Objective & Projective Objective Personality Tests present specific stimuli and ask for specificresponses (e.g. true/false questions) .Projective Personality Tests present more ambiguous stimuli and ask for lessspecific responses (e.g. inkblots, drawings,photographs, Rorschach, TAT)Psy 427 - Cal State Northridge17History of Psychometrics Chinese influenceIndividual Differences: Darwin and GaltonExperimental PsychologistsThe study of mental deficiencyIntelligence TestersPersonality TestersPsy 427 - Cal State Northridge186

History of Psychometrics:Chinese influence 2000 B.C.E. 206 B.C.E. to 220 C.E. Scattered evidence of civil service testing in ChinaHan Dynasty in China develops test batteries two or more tests used in conjunction.Test topics include civil law, military affairs, agriculture,revenue, geographyPsy 427 - Cal State Northridge19History of Psychometrics:Chinese influence 1368 C.E. to 1644 C.E. Ming Dynasty in China develops multistagetestingLocal tests lead to provincial capital tests; capitaltests lead to national capital testsOnly those that passed the national tests wereeligible for public office1832 English East India Company copies Chinesesystem to select employees for overseas duty.Psy 427 - Cal State Northridge20History of Psychometrics:Chinese influence 1855 British Government adopts English East IndiaCompany selection examinations.French & German governments follow shortly.1883 United States establishes the American CivilService CommissionDeveloped & administered competitiveexaminations for government service jobs.Psy 427 - Cal State Northridge217

History of Psychometrics: IndividualDifferences, Darwin and Galton Individual differences - despite oursimilarities, no two humans areexactly alike.Why?Darwinsome of these individual differences are more“adaptive” than othersthese individual differences, over time, lead tomore complex, intelligent organisms Psy 427 - Cal State Northridge22History of Psychometrics: IndividualDifferences, Darwin and Galton Galton - cousin of Darwin “Applied Darwinist”: some people possessedcharacteristics that made them “more fit”than others.Wrote Hereditary Genius (1869)Sets up an anthropometric laboratory at theInternational Exposition of 1884For 3 pence, visitors could be measuredwith: The Galton Bar - visual discrimination of lengthThe Galton Whistle (aka “dog whistle” determining highest audible pitchPsy 427 - Cal State Northridge23History of Psychometrics: IndividualDifferences, Darwin and Galton Galton’s Anthropometric LabPsy 427 - Cal State Northridge248

History of Psychometrics: IndividualDifferences, Darwin and Galton Galton Whistle (circa 1900) Galton BarPsy 427 - Cal State Northridge25Individual Differences:Darwin and Galton Galton also noted that persons with mentalretardation also tend to have diminished abilityto discriminate among heat, cold & pain.Other advances (?) of Galton’s: Considered by some the founder of psychometricspioneered rating scales & questionnairesfirst to document individuality of fingerprintsstudied efficacy of prayerfirst to apply statistics in the measurement of humansFounder of eugenicsPsy 427 - Cal State Northridge26History of Psychometrics: Galton’sFamous Students Karl Pearson Does the name Pearson sound familiar?student of Galtonextended Galton’s early work withstatistical regressionJames McKeen Cattell first to use the term “mental test”U.S. dissertation on reaction time basedupon Galton’s workPsy 427 - Cal State Northridge279

History of Psychometrics:Early Experimental Psychologists Early 19th century scientists, generallyinterested in identifying common aspects,rather than individual differences. Differences between individuals wasconsidered a source of error which renderedhuman measurement inexact.Sounds a lot like things from your past (e.g.ANOVA) and your coming futurePsy 427 - Cal State Northridge28History of Psychometrics:Early Experimental Psychologists Johan Friedrich Herbart - mathematicalmodels of the mind; founder of pedagogy asan academic discipline; went against KantErnst Heinrich Weber - sensorythresholds; just noticeable difference (JND)Gustav Theodor Fechner - mathematics ofsensory thresholds of experience; founderof psychophysics; considered of onefounders of experimental psychology;Weber-Fechner Law first to relate sensationand stimulus; considered by some thefounder of psychometricsPsy 427 - Cal State Northridge29History of Psychometrics:Early Experimental Psychologists Fechner influenced many prominentpsychologists (e.g. Wundt, Freud) Wilhelm Wundt – considered one of thefounders of psychology; first to set up apsych laboratoryEdward Titchner – succeeded Wundt;brought Structuralism to America; Hisbrain is still on display in the psychologydepartment at CornellPsy 427 - Cal State Northridge3010

History of Psychometrics:Early Experimental Psychologists Fechner influenced many prominentpsychologists (e.g. Wundt, Freud) Guy Montrose Whipple – Student ofTitchner’s; pioneer of human ability testing;conducted seminars that changed the field ofpsych testing; APA issued its first set ofstandards for professional psychologicaltesting because of his criticismsLouis Leon Thurstone – Large contributor tofactor analysis; attended Whipple’s seminars;approach to measurement was termed thelaw of comparative judgmentPsy 427 - Cal State Northridge31History of Psychometrics:Interest in Mental Deficiency 1805 – Jean-Étienne Esquirol, French Physician Favorite Student of Philippe Pinel (founder ofpsychiatry)Manuscript on “mental retardation.” Many degrees to mental retardation differentiated between insanity & mental retardationinsanity had a period of normal intellectual functioningnormality to “low-grade idiocy”Attempted to develop system to classify people intothese many degrees but found that the individual’s useof language provided the most dependable continuumPsy 427 - Cal State Northridge32History of Psychometrics:Interest in Mental Deficiency 1840s - Edouard Seguin, FrenchPhysician Pioneer in training mentally-retarded persons.Rejected the notion of incurably MR1837: opens first school devoted to teaching MRchildren.1848: emigrates to USA, wide acceptance of theories1866: experiments with physiological training of MR sense-training / muscle-training still used todayleads to nonverbal tests of intelligence (Seguin Form Board)Psy 427 - Cal State Northridge3311