Assessment Midterm Flashcards
Nominal Scale
mutually exclusive categories
Ordinal Scale
order; magnitude
Interval Scale
equal units between points; an arbitrary zero point
Ratio Scale
a true zero point
Norm-Referenced Measurement
a child’s performance is compared with that of a representative group of children
-norm group or standardization sample
Standardized Test
require standardized administration and scoring procedure
-scores are transformed, or standardized, relative to the norm group
Representativeness
the extent to which the groups characteristics match those of the population of interest
% within 1 Z-Score (standard deviation)
68.26%
% within 2 Z-Scores (standard deviation)
95.44%
r^2
the amount of variance shared between two variables
rXY
Correlation coefficients
- the degree to which two variables covary
- ranges from -1.0 to 1.0
Factor Analysis
used to explain the pattern of inter-correlations among variables in a complex set of data
-ex) factors in the WISC-V; factor loading (correlation between a subtest and a factor/index)
Factor Loading
correlation between a subtest and a factor/index
Reliability
ratio of the true score variance to the observed score variance
-the extent to which random/unsystematic variation affects the meaurement of a trait
Classical Test Theory
X (observed score) = T (true score) + E (error)
Cronbach’s alpha
uniformity or homogeneity of items
-test length, item heterogeneity and alpha
Test-Retest Reliability
evaluate the test for stability over time
Alternate-Forms Reliability
two different forms of the same test at different times
-see if it is a reliable form of testing
Inter-Rater Reliability
the degree to which the raters agree
Validity
does it measure what it is supposed to measure?
Content Validity
do the items represent the domain being assessed?
-relatively subjective; unsystematic evaluation procedure
Construct Validity
the degree to which a test measures a purported psychological construct/trait
Criterion-Related Validity
the extent in which a measure is related to an outcome
- ex) correlation between Total Reading should be be more highly correlated with reading domains
- often divided into Concurrent and Predictive Validity
Concurrent Validity
a comparison between the measure in question and an outcome assessed at the same time
Percentile Ranks
an individual’s position relative to the standardization sample
Standard Error of Measurement (SEM)
an estimate of the amount of error in obtained scores; the standard deviation of the distribution of error scores
Predictive Validity
iq at age 12 predict your iq later in life
Divergent Validity
tests assess different areas
-ex) testing cognition vs. adaptive skills