PSYB01H3 Lecture : june 14 lecture
Document Summary
Reliability: the proportion of truth in a measure; reliability is looked at over a large number of subjects leads to a variability in scores. Not looking at mean scores but how variance differs in scores. Multiple choice questions on reliability, not short answer. The proportion of true score in each measure. True score (we don"t know) is the same, especially over a short period of time. Variance of true score (t)/ variance of measure (x) No, can"t calculate variance of true scores because won"t know what they are. Can assume our measurement scores share a true score. Measurement scores are related to each other to the degree that they share true scores. Estimate"s of reliability reliability coefficients (pearson"s coefficients) =variance of true score/ variance of true score + variance of measurement error i. e. two scores on a test; first time you score 85, second time you only score 80. x1 = 85, x2=80 these are sample measures.
