1. Chapter Five Measurement Concepts

2. Terms • Reliability • True Score • Measurement Error

3. How Can we assess Reliability • Test-Retest Reliability • Internal Consistency Reliability • Split half reliability • Cronbach’s alpha • Inter-rater reliability

4. Reliability vs. Validity • Reliability-consistency of the measure • Validity-truth---does the study measure what it says it will measure…is it valid • ****A measure can be reliable and not valid, but it canno be valid unless it is reliable.

5. Construct validity the adequacy of the operational definitions of variables • Criterion-Oriented Validity- examining the relationship between scores on a measure and some criterion.

6. Indicators of Validity • Face validity tells whether the measure appears to measure what it is suppose to.. • Four types of Criterion-related research approaches

7. Types of Criterion-oriented research approaches • Predictive Validity • Concurrent Validity • Convergent Validity • Discriminant Validity

8. Predictor Validity- research measuring the extent to which the measure allows you to predict future behaviors. (SAT) • Concurrent Validity-examines the relationship between the measure and a criterion at the same time. • research whether two or more groups of people differ on a measure in expected ways. • Convergent validity when a measure relates to other scores of the same or similar constructs in a meaningful and predicted way. • Shy Q scores and Fear of Negative Evaluation Scale • Discriminant validity the measure should discriminate between the construct being measured and other non-related constructs. • Shy Q and Zuckerman’s Sensation seeking Scale.

9. Variables & Measurement Scales • Nominal scales have no numerical or quantitative properties, they are naming scales, and their only property is identity . • Ordinal scales tell us about the relative order of magnitude, but they do not give us info about the differences b/t categories or ranks. • Interval scale the measurement conveys info about the order and the distance b/t the values • Ratio scales have all the properties of the previous scales and a true zero point that indicates the absence of the variable being measured