2Overview History of General Mental Ability Measures of GMA Definition, ModelsMeasures of GMAApplicationsGMA and Job PerformanceIndividual DifferencesRace, Gender, AgeAlternatives?
3What is GMA?It goes by many names: g, general mental ability, IQ, intelligenceA general measure of cognitive functioning that should work across several different domainsFirst proposed by Francis Galton (1888), an English geneticist and relative of DarwinSpearman (1904) proposed “g”- a general underlying intelligence factor that accounted for correlations between different areas on measures of intelligence.It remains one of the most studied of all human characteristics
5Just how positively correlated are these subdimensions? Correlation between the supposedly distinct ACT and SAT?R=0.91; R2=0.82
6General mental ability and stability The genetic inheritance of GMATwo statistics:h2 (genetic effect)c2 (shared effect)The effects of heredity only get stronger with age
7Correlates of GMA Childhood outcomes General psychomotor skills Average r=0.50 with school performanceHowever, children in Japan and China know more math than American children even though IQ scores are very similarAverage r=-0.19 with juvenile crimeGeneral psychomotor skillsReaction speed r=.30Judgment speed r=.55
8GMA and Stability Is it really a trait? Is it stable? Test re-test Age 6 to 18=0.77Age 12 to age 18=0.89Even higher correlations if tests are given on multiple occasionsWhat does this mean?It means that rank order is very stable over timeIt does not mean that an average (100 IQ) 6 year old can do what an average 18 year old can do
9Data clearly show that general mental ability as measured by the ASVAB is correlated with education levels, income, self-esteem, and weeks of unemployment even with a 10-year gap between measures
10Measures of GMA General Aptitude Test Battery (GATB) Wonderlic Personnel TestArmed Services Vocational Aptitude Battery (ASVAB)IQ Tests (WAIS-IV, Stanford Binet, etc.)
11Examples of items from the Wonderlic Personnel Test Fairness in Employment Testing: Validity Generalization, Minority Issues, and the General Aptitude Test Battery (1989)
14Overall it seems like GMA is a perfect selection tool It’s very stable over timeIt’s related to measures of learning ability and adaptabilityIt’s one of the best predictors of job performance availableThe tests are cheap (about $2.00 per applicant tested)It really doesn’t matter which test you use since they all measure the same thingBut…
15…there are potential problems with GMA test scores The subtests show differences for genderWomen score higher on verbal intelligenceMen score higher on visual-spatial intelligence and the math section of the SATThese differences are not very great and there are massive overlapsHowever, overall IQ scores are basically equivalent for men and women
16GMA Scores and Race/Ethnicity There are clear differences in GMA scores based on ethnicityAfrican-Americans scored about 1 SD below Whites, although more recent data suggests this difference is closer to 0.6 to 0.7 SDLatinos score between Whites and African- AmericansAsians score slightly higher than WhitesAshkenazi Jews score about ½ SD higher than other White groups
17Returning to our conception of biased from earlier GMA tests predict just as well for both groups, but one group gets lower scoresThis passes the equity standard, but not equalityThere is no factual or logically rigorous reason to say this is okay or not
18GMA for selection1 Spearman, C. (1927). The Abilities of Man. New York: Macmillan.2 Neisser et al., (1996). Intelligence: Knowns and unknowns. American Psychologist, 51,3Schmidt, F. L., & Hunter, J. E. (1998). The validity and utility of selection methods in personnel psychology: Practical and theoretical implications of 85 years of research findings. Psychological Bulletin, 124,4 Hunter, J. E. (1980). Validity generalization for 12,000 jobs: An application of synthetic validity and validity generalization to the General Aptitude Test Battery (GATB). Washington, D.C.: U.S. Department
19Study Occupation On the job In training The Relation Between General Mental Ability (GMA) and Performance in Job Training and on the Job: Representative Findings From Meta-AnalysesPerformance measuresStudy Occupation On the job In trainingHunter and Hunter (1984) Medium complexityPearlman et al. (1980) ClericalHirsh et al. (1986) Law enforcementMcHenry et al. (1990) Military—enlisted .63b NRMcHenry et al. (1990) Military—enlisted .65c NRHunter (1986) Military—enlisted NR .63Ree et al. (1994) Military—enlisted NRRee and Earles (1991) Military—enlisted NR .60Schmidt et al. (1979) First-line supervisors NRSchmidt et al. (1979) Administrative clerks NRSchmidt et al. (1980) Computer programmers NRCallender and Osburn (1981) Refinery workers
20Applicant reactions to GMA tests In general, results suggest applicants tend to find GMA tests acceptableThey especially like tests that are called “personnel tests”They like tests more when they are paired with individual interview informationThey usually like tests of knowledge and abilities more than they like personality tests or biodata.
21Bobko, Roth, & Potosky: Cognitive Ability and Alternative Predictors Their meta-analytic matrix shows that structured interviews, conscientiousness, and biodata all have much lower d-scores than cognitive ability in terms of prediction, and many of these alternatives have good correlations with job performance
22Validity vs. ValueGMA is the single strongest predictor of performanceValue of interviews, collecting biometric data, etc.?
23To wrap it up…GMA is the totality of mental processes involved in adapting to the environment.Underlying component of all different aspects of intelligence.Stable over time, strong genetic/heredity componentStrong predictor of future job performance, especially with complex and technical jobs.People like GMA tests.Value of alternatives?