578 Midterm Flashcards
Psychological Measurement/Psychometrics
Conveys meaningful information about people’s attributes, such as intelligence, reading ability, adaptive behaviors, interests, personality traits, and attitudes, through test scores and ratings that reflect such attributes.
Statistical Analysis
Helps us reduce large amounts to a manageable size to help us study.
Measurement
Helps us describe variability in human characteristics.
Score
Helps us assign a value to commonly measured characteristics, so we understand how variable they are.
Scales of Measurement
Is a scale system for assigning values or scores to some measurable trait or characteristic.
Nominal Scale
Sets of categories without order
Ordinal Scale
Sets of categories with order
Interval Scale
Sets of categories with order, zero point, and equal intervals between units.
Ratio Scale
Set of categories with true zero point and equal intervals between units.
Descriptive Statistics
summarizes data obtained about a sample of individuals. Ex. frequency distribution, normal curves, standard scores, measures of central tendency, measures of dispersion, correlation, and regression.
Measures of Central Tendency
identifies a single score that best describes the scores in a data set.
Mean
average score
Median
middle score
Mode
most occurring score
Dispersion
the variability of scores in a set or distribution of scores
Range
highest to lowest
Variance
difference from the mean
Standard Deviation
how much scores deviate from the mean
Normal Curve
a frequency distribution that, when graphed, forms a bell-shaped curve called the normal curve
Criterion-referenced
Performance is compared to an objective standard. Ex. 90% of material mastered.
Standards-referenced
The degree to which a defined standard is met. Ex. proficient, advanced, poor, etc.
Norm-referenced
Performance compared with the performance of a representative group (norm group or standardization sample) Ex. 80% when compared to all 8th graders.
Derived Scores
Standard scores, percentile rank, and age and grade equivalate scores.
Standard Scores
Raw scores that have been transformed so that they have a predetermined mean and standard deviation.