Psychology 2080A/B Lecture Notes - Lecture 4: Standard Error, Internal Consistency, Item Response Theory

• School: Western University
• Department: Psychology
• Course: Psychology 2080A/B
• Professor: Doug Hazlewood

Document Summary

Connecting sources of error with reliability assessment method. Standard errors of measurement and the rubber yardstick. Describe the role of measurement error in scientific studies of behavior. Know that reliability is the ratio of true variability to observed variability and explain what this tells us about a test with a reliability of . 30, . 60, or . 90. Explain the difference between test retest reliability estimates and split-half reliability estimates. Discuss how high a reliability coefficient must be before you would be willing to say the test is reliable enough . Discuss how the split-half method underestimates the reliability of a short test and what can be done to correct this problem. Know the easiest way to find average reliability. Define coefficient alpha and tell how it differs from other methods of estimating reliability. Explain what can be done to increase the reliability of a test. Tell how the reliability of behavioral observations is assessed.