PSYB01H3 Chapter Notes - Chapter 5: Inter-Rater Reliability, Discriminant Validity, Content Validity
Document Summary
Reliability: consistency or stability of a measure of behaviour. A reliable measure does not fluctuate from one reading to another. Proportion of true scores in a measure: variance of true scores (t) / variance of the measure (x) True score: real score on the variable. Measurement error: unreliable measure of intelligence contains considerable measurement error. Reliability can be increased by making multiple measures. Test-retest reliability: assessed by measuring the same individuals at two points in time. The correlation maybe artificially high because the participants remember how they responded the first time. Alternate forms reliability is used to avoid this problem: it requires administering two different forms of the same test to same individuals at two points in time. Internal consistency reliability: assessment of reliability using responses at only one point in time. Split-half reliability- the correlation of the total score on one half of the test with the total score on the other half.
