Slide 1 ___________________________________ - - PDF document

Slide 1

Chapter Five

Measurement Concepts

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 2

Terms

• Reliability
• True Score
• Measurement Error

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 3

How Can we assess Reliability

• Test-Retest Reliability
• Internal Consistency Reliability

– Split half reliability – Cronbach’s alpha

• Inter-rater reliability

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________

Slide 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.

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 5

• Construct validity  the adequacy of the
• perational definitions of variables
• Criterion-Oriented Validity- examining

the relationship between scores on a measure and some criterion.

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 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

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________

Slide 7

Types of Criterion-oriented research approaches

• Predictive Validity
• Concurrent Validity
• Convergent Validity
• Discriminant Validity

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 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

• ther non-related constructs.

– Shy Q and Zuckerman’s Sensation seeking Scale.

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ Slide 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

• f the variable being measured

___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________