Transcript Intro to Psychological Testing (part I)

Intro to Psychological
Testing (part II)
Clinical Judgment
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Do clinicians have
special powers of
intuition?
Can clinicians predict
behavior better than
other people?
Does experience
improve clinicians’
judgments?
Factors That Limit Clinical
Judgment
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Lack of feedback on
outcomes
Inability to use
feedback (hindsight
bias)
Confirmation bias
Illusory correlations
and missing cells
Weighting information
inappropriately
Overconfidence
Some Principles of Test
Interpretation
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Extreme scores tell you
more than normal
range scores
Do not over-interpret
differences between
scales
Test interpretations are
only hypotheses, not
facts
Look for patterns; don’t
rely on single
indicators
Don’t assume the test
is wrong if it doesn’t
match your intuition
Descriptive Statistics
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Measures of Central
Tendency
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Mode
Mean
Median
Measures of Variability
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Standard deviation
Normal Curve
Score Transformations
_
z= X–X
SD
New score = z*NewSD +
NewMean
T = 10z + 50
IQ = 15z + 100
Correlation
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Looks at the
relationship between
two things
Scatterplot
Correlation coefficient
Restriction of Range