Reliability and Validity Scale Evaluation Reliability Validity Test-Retest Internal Consistency Alternative Forms Construct Criterion Content Convergent Validity Discriminant Validity Nomological Validity
Determination of Validity and Reliability
Multitrait - Multimethod Matrix (Campbell & Fiske, 1959) b 1 = reliability for method 1 v a = convergent validity for both methods wrt trait a m 1 = discriminant validity for method 1 d= “nonsense”-correlation Requirements: v > 0 and "high enough" v > d v > m d low Correlation coefficients {
Example Mosher Forced Choice Guilt Scale 3 traits Guilt feelings about sex Hostile guilt Guilt concerning morality 3 methods Incomplete sentences "When I dream about sex …" Forced choice " When I dream about sex …" a) I don't remember a thing in the morning b) I feel happy when I get up True/False "When I dream about sex I wake up feeling happy"
MTMM matrix for the Mosher Forced Choice Guilt Scale Sexual Hostile Morality FC very reliable, TF too, IS not Good convergent validity Discriminant validity OK