Tests and Measurements: Reliability

1
Tests and Measurements Reliability

• Definition Consistency of scores
• Test - Retest Reliability
• Across time
• Can you repeat the test and get the same results?
• Alternate forms can be used to reduce the chances
  of becoming test-wise
• Internal Reliability
• Split-half
• Can you split the test items and each half give
  you the same results?

2
Tests and Measurements Validity

• Definition The ability of a test to measure what
  it was designed to test
• Face validity
• Does it look like it measures what it is suppose
  to measure?
• Content validity
• Do the test items represent the trait in
  question?
• Criterion validity
• Does the difference in scores indicate real
  differences in behavior?
• Concurrent validity
• Predictive validity
• Construct validity
• Does the construction of the test reflect the
  theory on which it is based?