Intro to Psychological Testing (part II)

1
Intro to Psychological Testing (part II)
2
Clinical Judgment

• Do clinicians have special powers of intuition?
• Can clinicians predict behavior better than other
  people?
• Does experience improve clinicians judgments?

3
Factors That Limit Clinical Judgment

• Lack of feedback on outcomes
• Inability to use feedback (hindsight bias)
• Confirmation bias
• Illusory correlations and missing cells
• Weighting information inappropriately
• Overconfidence

4
Some Principles of Test Interpretation

• 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 dont rely on single
  indicators
• Dont assume the test is wrong if it doesnt
  match your intuition

5
Descriptive Statistics

• Measures of Central Tendency
• Mode
• Mean
• Median
• Measures of Variability
• Standard deviation

6
Normal Curve
7
Score Transformations

• _
• z X X
• SD
• New score zNewSD
• NewMean
• T 10z 50
• IQ 15z 100

8
Correlation

• Looks at the relationship between two things
• Scatterplot
• Correlation coefficient

9
Restriction of Range