1. XI. Testing and Individual Differences
College Board - “Acorn Book”
Course Description
5-7%
Unit XI. Testing and Individual Differences

2. Summary Outline A. Standardization and Norms
B. Reliability and Validity
C. Types of Tests
D. Ethics and Standards in Testing
E. Intelligence
F. Heredity/Environment and Intelligence
G. Human Diversity
Unit XI. Testing and Individual Differences

3. A. Standardization and Norms
Normal Distribution
Normal Curve (Bell shaped curve)
Standard Deviation and Percentages in the Normal Distribution
Unit XI. Testing and Individual Differences

4. Normal Distribution Curve

5. Relationships between Standard Deviation and various scores
Standard Deviations
- 3sd sd sd Mean +1sd sd sd
Out of 1000
‘ interval 1 22
136
341
% / interval
0.13%
2.14%
13.59%
34.13%
% / Cumulative
2.27%
15.86%
50%
84.13%
97.72%
99.86%
99.99%
Percentiles
Stanford -Binet IQ
Unit XI. Testing and Individual Differences

6. Reliability The higher the reliability of a test
the less likely it is that its scores will be affected by irrelevant changes in the environment or the test taker
To estimate the reliability of a test
get two sets of scores on the same test from the same people
compute a correlation coefficient between the two
Test-retest Reliability
Alternate-forms Reliability
Split-half Reliability
Unit XI. Testing and Individual Differences

7. Validity Does the test measure what it purports to measure
Validity refers to the degree to which
Test scores are interpreted appropriately
Test scores are used properly
In other words the test may be “valid” but used improperly
Unit XI. Testing and Individual Differences

8. Content Validity
the degree to which the content of a test is a fair and representative sample of what the test is supposed to measure
A test on addition
that measures addition skills has content validity
that measures subtraction or is used to measure intelligence does not have content validity does not have content validity
If a class test contains questions about material that was not covered in lectures and assigned reading and the content validity is low
Unit XI. Testing and Individual Differences

9. Criterion Validity / Predictive Validity
If you need to hire individuals to check your account books one of the criterions for the job is math skill
A test used to measure math skills in applicants would have criterion validity
A test used to predict if applicants will be able to successfully complete training would need to have predictive validity
Both predict how well an individual will perform
Unit XI. Testing and Individual Differences

10. Construct Validity You need a test to measure depression
You construct the test based on theories how depression affects behavior and thoughts
The degree to which a test measures the theoretical construct that it claims to measure is its construct validity
Unit XI. Testing and Individual Differences

11. Debate over Reliability and Validity of IQ Tests
Is intelligence fixed or does it change over time?
Is intelligence subject to changes depending on external or individual environment?
Unit XI. Testing and Individual Differences

12. Validity Is there a single intelligence “g” or
Is intelligence a number of factors
Does an intelligence test measure “g” or does it measure individual skills or factors
Does intelligence measure “g” or is it subject to cultural and environmental influences
Unit XI. Testing and Individual Differences

13. C. Types of Tests History of IQ Tests: Intelligence Tests
Sir Francis Galton – Individual Differences
Alfred Binet – Mental Age
William Stern - Intelligence Quotient
Lewis Terman (Stanford-Binet)
Intelligence Tests
Stanford-Binet
Wechsler Scales (WAIS, WISC)
Aptitude Tests
Achievement Tests
Personality Tests
Unit XI. Testing and Individual Differences

14. D. Ethics and Standards in Testing
Fairness of IQ testing
Cultural Differences
Group differences in IQ
Bias of IQ tests
Unit XI. Testing and Individual Differences

15. E. Intelligence Definitions Factor Analysis: The “g” factor (Spearman)
Primary Mental Abilities (Thurstone)
Structure of Intellect – Operations, Products, Contents (Guilford)
Fluid Intelligence / Crystallized Intelligence (Cattell)
Multiple Intelligences (Gardner),
Triarchic Theory (Sternberg)
Unit XI. Testing and Individual Differences

16. F. Heredity/Environment and Intelligence
Intelligence - Stability or Change?
Heredity –
variation due to genetic factors in the individual
Heritability –
variation due to genetic factors in the population
Heredity Influences vs. Environmental Influences
Twin Studies
Adoption Studies
Environmental Deprivation and Enrichment
Interaction of Heredity and Environment
Unit XI. Testing and Individual Differences

17. G. Human Diversity Creativity
Giftedness - Mental Retardation - Learning Disabilities
Gender and Race
Socioeconomic Disadvantage, Effects of Stereotyping, Cultural Bias
Unit XI. Testing and Individual Differences