evidence for heredity influence - amazon web services · benefits of iq tests –iq questions are...

Intelligence • The ability to learn

from experience, solve problems, and use knowledge to adapt to new situations. Remote Associates Test

Call,pay,line ,____________ End,burning, blue,_________ Man, hot, sure, __________ Stick, hair, ball, __________ Blue, cake, cottage, _________

• Psychological Testing- standardized measure of a person’s behavior

• Principle Types of Tests: • Intelligence Tests: measure

mental ability-WISC • Aptitude Tests: measures

types of mental abilities-SAT • Achievement Tests: Gauge a

persons knowledge of certain subjects-AP

ALL TEST MUST BE RELIABLE, VALID AND STANDARDIZED

• Standardization: uniform procedures used in administration of tests

• Reliability: consistency of test scores • Validity: ability of a test to measure what it is

designed to measure

– Test Norms: give information about where a score ranks in relation to others scores in psychological testing

– Percentile Score: the percentage of people who score at or below the score one obtained. (If you scored a 90% percentile you did better than 90% of the people that took the test.)

VALIDITY – Content Validity: degree to which the content of the

test is represented in the domain it should cover (math questions on a math test)

– Criterion-Related Validity: estimated by correlating subject scores on a test with the scores of an independent criterion (a gifted person should score around a 1200-1400 on the SAT)

– Construct Validity: extent to which there is evidence that the test measures a certain hypothetical construct (employment test)

The Evolution of Intelligence Testing

• Galton’s Studies of Hereditary Genius – Nature versus Nurture referring to the heredity-

environment issue – Invented the correlation and percentile test

scores. • Binet’s Breakthrough

– Mental Age: indicates the ability of a typical child of actual age.

• Binet & Simon - discovered that someone’s mental age can predict future performance.

• Hoped they could use test to help children, not label them.

• Terman and Stanford Binet –Stanford Binet Intelligence Scale –Intelligence Quotient: a child’s mental age

divided by actual age, multiplied by 100 • IQ=(Mental Age/Chronological Age)X100

Measure Child 1 Child 2 Child 3 Child 4

Mental Age (MA) 6 years 6 years 9 years 12 years

Chronological Age (CA)

6 years 9 years 12 years 9 years

IQ= (MA/CA)X100 (6/6)x 100= 100

(6/9)x 100= 67

(9/12)x 100= 75

(12/9)x 100= 133

Intelligence Testing Today

• Wechsler’s Innovations

–Wechsler Adult Intelligence Scale –Individual Tests: Stanford-Binet and

the Wechsler –If someone scores low on an IQ test does it absolutely mean they have a low IQ?

Basic Questions About Intelligence Testing

• What do Modern IQ Scores Mean? –Normal distribution: a symmetric, bell

shaped curve that represents a population

–Deviation IQ Scores: normal distribution of a mean of 100 & Standard deviation of 15.

Benefits of IQ tests

–IQ questions are diverse depending on whether the test is for a child or adult, or individual or group basis.

– IQ tests are meant to measure intellectual potential but they can measure both potential and knowledge.

–IQ tests can help place children in special programs to get their needs met.

–Children can have individualized education plans according to their IQ.

Extremes of Intelligence

• Mental Retardation: the lower general mental ability accompanied by deficiencies in adaptive skills, originating before the age of 18 – Levels of Retardation:

• 2%-3% of school-age kids are labeled mentally retarded

• Must have an IQ below 70

• Four levels: mild, moderate, severe, and profound

Extremes of Intelligence • Giftedness

– Identifying Gifted Children • Most consider the top 2%-3% of the IQ

distribution to be gifted. • Must have an IQ over 130

– Giftedness and Achievement Level • Innate talent hard work

Heredity and Environment as Determinants of Intelligence

• Evidence for Heredity Influence – Twin Studies Reared together or apart

– Adoption Studies – Hereditability Estimates

Evidence for Environmental Influence

– Adoption Studies • Some found that adopted children are very

similar to biological parents in intelligence – Environmental Deprivation and Enrichment

• Substandard environment should cause a declining effect in IQ scores

– Home Environment and Schooling Effects – Generational Changes: The Flynn Effect

• Environmental factors

FLYNN EFFECT

Heredity and Environment as Determinants of Intelligence

• Cultural Differences in IQ Scores: –Socioeconomic Disadvantage as an

Explanation –Cultural Bias on IQ as an Explanation:

•Since IQ tests are made by white middleclass men there is test bias.

New Directions in the Assessment and Study of Intelligence

• Increasing Emphasis on Specific Abilities: –Charles Spearman: General Intelligence –Factor Analysis: correlations among many

variables are analyzed to identify closely related clusters of variables

–Fluid Intelligence: reasoning ability, memory capacity, and speed of information processing

–Crystallized Intelligence: ability to apply acquired knowledge and skills in problem solving

• Expanding the Concept of Intelligence –Howard Gardener –Multiple intelligence

• Measuring Emotional Intelligence –Daniel Goleman –Emotional Intelligence: the ability to

perceive and express emotion, assimilate emotion in thought, understanding and reason with emotion, and regulate emotion

Gardner’s Multiple Intelligences

• Visual/Spatial • Verbal/Linguistic • Logical/Mathematical • Bodily/Kinesthetic • Musical/Rhythmic • Interpersonal • Intrapersonal • Natural

Learn More about Gardner

Sternberg’s Three Aspects of Intelligence

Gardner Simplified • Analytical (academic

problem solving). • Creative (generating

novel ideas) • Practical (required

for everyday tasks where multiple solutions exist).

Personal Application • The Nature of Creativity

–Creativity: the generation of ideas that are original, novel, and useful

–Convergent Thinking: narrowing down a list of alternatives to converge on a single answer

–Divergent Thinking: expanding the range of alternatives by generating many possible solutions

Objective vs Projective (subjective) tests

IQ • Wechsler- 11 subtest - most popular • Stanford Binet - Mental illness/diagnosis • MMPI-567 questions, 14 scales Therapy • TAT-10-12 cards out of 30 • Rorschach-10 cards

Appendix B: Statistical Methods • Statistics: the use of mathematics to

organize, summarize, and interpret numerical data

• Graphing Data –Frequency Distribution: an orderly

arrangement of scores indicating the frequency of each score or group of scores

–Histogram: a bar graph that presents data

–Frequency Polygon: a line figure used to present data from a frequency distribution

–Descriptive Statistics: used to organize and summarize data

• Measuring Central Tendency –Median: the score that falls in the middle of

a distribution –Mean: the average of the scores –Mode: the most common score

–Negatively Skewed Distribution: most scores pile up at the high end of the scale

–Positively Skewed Distribution: most score pile up at the low end of the scale

• Measuring Variability –Variability: how much the scores tend to

vary or depart from the mean score –Standard Deviation: an index of the

amount of variability in a set of data

• The Normal Distribution: a symmetric, bell-shaped curve that represents the population –Percentile Score: the percentage of people

who score at or below the score you got

• Measuring Correlation: – Correlation Coefficient: numerical index of the

degree of relationship between two variables (+1,0,-1)

– Scatter Diagram: a graph in which paired X and Y scores for each subject are plotted as single points.

• Correlation and Prediction –Coefficient of Determination: percentage of

variation in one variable that can be predicted based on the other variables

• Hypothesis Testing –Inferential Statistics: used to interpret data

and draw conclusions –Null Hypothesis: the assumption that there

is no true relationship between the variables observed