Exam One Flashcards
Psychological testing
Refers to all possible uses, applications, and underlying concepts of psychological and educational tests.
Psychologists’ responsibility around test administration
Duty to select fair (representative), appropriate, updated, reliable and valid tests as scores drive decision-making
Types of psychological tests
- Achievement- refers to previous learning (course material)
- Aptitude- refers to the potential for learning or acquiring a specific skill (SAT)
- Intelligence- general potential to solve problems, adapt, think abstractly, and learn from experience
Types of personality tests
Structured/Objective- multiple choice, true/false,
or Likert scale format, usually self-report
Projective- test materials or required response
(or both) are ambiguous (Rorschach)
How to evaluate utility of tests
Aspects of psychometric soundness
- reliability (consistency)
- validity (accuracy)
Test construction
- item creation and/or selection
- logical vs. theoretical vs. empirical considerations
Test administration
-variation in scores due to administrator, examinee,
and/or random error
Early antecedents for tests
Han Dynasty - Test batteries used for work-related evals
Ming Dynasty- testing rounds in testing centers used to nominate public officials
British missionaries- civil service test system
US- American Civil Service Commission
Darwin/Galton
Darwin
-The Origin of Specices: Evolution acts upon individual differences (survival and reproduction of the fittest)
Galton
-Documented individual differences in cognitive and physical abilities
-Founder of eugenics (selective reproduction
of individuals with “desirable” traits
Cattell
-Individual differences in cognitive and physical abilities
-Coined the term “mental tests”
Experimental psychologists
Donders
- reaction time tests
- cognitive psych experiment
Wundt
- First psych lab
- Sensation and perception
This era drove scientific method of psych testing
(requires rigorous experimental control)
Intelligence tests
Binet-Simon scale- first intelligence test, first use of standardized sample
Stanford-Binet scale- US version; standardized
sample- 1000, edited and new items
Group tests- developed in response to WWI by Yerkes; Army Alpha and Army Beta (1917)
Wechsler Intelligence Tests - included nonverbal subscale of intelligence (“performance”)
standardized sample
norm-based sample = comparing score to other people
representative sample
comprises individuals similar to those for whom the test is to be used
Mental age
measurement of a child’s performance relative to other children of that age group
Personality tests
- measures traits
- Woodworth Personal data sheet- military recruits likelihood of “shell shock”
- Rorschach
- Thematic Apperception Test
Modern personality tests
Objective Tests - no assumptions about meaning
of a test response
MMPI, CPI, 16PF (based on factor analysis (finds minimum number of dimensions to account for large # of variables)
Descriptive statistics
Statistics describing the sample or population.
measures of central tendency and variance
-can be used with ANY type of data
-including experimental or non-experimental data
Inferential statistics
Statistical procedures that allow inferences to be made from the sample to the population.
-infer causality
-more limited to experimental data
-type of data dictates type of analysis used
-must be careful of data distribution
(parametric vs. nonparametric)
Nominal data
Categorical data; no mathematical meaning
(dichotomous if two categories)
gender; political party, religion, species, team
Ordinal data
Indicates order- cannot know how far apart each item is (no equal intervals)
first to last; most to least
-basketball standings, sibling-line position, IQ scores
Interval data
True score data but there is no true zero; does not have equal intervals.
- temperature in degrees, SAT scores
- most psychological measures; Likert scale
Ratio data
Interval data with true zero.
most physical measures- height, weight,
speed, distance, volume, area
Normal distribution
Bell shaped, symmetry around central tendencies
- most stat procedures in PSYC assume normally
distributed scores
- parametric stats are based on symmetrical
(normal) distributions
Characteristics of parametric distributions
-approximate symmetry
-the distribution can be divided into standard deviation units
-the size of the deviation can be mathematically
defined on any measure that is interval or ratio in nature (skew)
Skew
The degree of departure from symmetry
Positively skewed- most S’s fall on the L side; tail skews right.
Negatively skewed- most S’s fall on the R side; tail skews left
Bimodal- 2 areas of the curve at equal frequencies with a dip in between
Variance
The variation of or differences among people in a distribution across the measure X
- arises from natural, random differences among Ss
- environmental variations
- measurement error
- researcher error (overt, covert)
Percentile ranks and how to calculate
Percentile ranks- the percentage of scores that
fall below particular score within distribution
Calculate:
- divide number of cases below the score of interest by total number of cases in the group
- multiply results by 100
Standard scores
z-scores: raw scores that are converted to fixed mean and standard deviation
-score measured in SD units (the deviation of a score from the mean in SD units)
Calculating a z-score
- Find difference between observed score and mean for the distribution
- Divide difference by SD of distribution
Mean exam score= 11.05 (SD is 7.01)
For a score of 14, z score is .42
Norms
Allow for evaluation of one’s performance relative to a larger group
Norm-referenced tests
-each test taker’s performance evaluated against standardized sample
-typically used for the purpose of making comparisons
with a larger group
-norms should be current, relevant, and representative
of the group to which the individual is being compared
Criterion-referenced tests
-represent predetermined level of performance to be reached (“benchmarks”)
-scores are compared to a preset “criterion score” (not
compared to others)
-No Child Left Behind
Correlations v. regression
Correlation assesses the magnitude and direction of a relationship. Regression is used to make predictions about scores on one variable from knowledge of scores on another variable. These predictions are obtained from the regression line (line of best fit).
Correlation coefficient (r)
-strength of association between variables
-Ranges between -1.0 and +1.0
-Calculating correlation between 2 variables for entire group, not 1 individual
-Reflects the amount of variability that is shared between 2 variables
+/- .10: weak, +/- .30: moderate, +/- .50: strong
p-value
Indicates whether the association is greater than what would be accepted by chance.
shared variance (r2)
Common variance, effect size, coefficient of determination
Correlation does not equal causation
- Mediating variables may explain the relationship
- Relationships can be bidirectional (thus both would be causal)
- Causality can be inferred only under experimental manipulations
Experimental conditions
Experiments:
- random assignment of participants
- manipulation of at least one independent variable
Coefficient of determination
Correlation coefficient squared and then converted into a percentage; indicates effect size