Business Research for Decision MakingSixth Edition

by

Duane Davis

Chapter 7

Foundations of Measurement

PowerPoint Slides for the Instructor’s Resource Manual for

Foundations of Measurement

concerned with the assignment of numbers to empirical rules according to a set of rules

goal is to translate characteristics and properties of empirical events into a form that can be analyzed.

1. Observable empirical events2. Use of numbers to represent these

events3. A set of mapping rules

Measurement:

NecessaryComponents:

Example of the Relationships Among the Three Components of MeasurementFigure 7.1

The Measurement ProcessFigure 7.2

Levels of Measurement

NominalOrdinalIntervalRatio

Nominal

Lowest level of measurement Numbers assigned to categories but

the numbers have no meaning1. 1= male; 2= female

2. 1= sophomore; 2 = junior; 3= senior Loss of information if other scales

converted to nominal

Ordinal

Rank order on some characteristic or property

Intelligence, aptitude, and personality test scores are generally ordinal E.g. not amount of intelligence, but rank order

of intelligence

No absolute zeros and the intervals are not equal.

Ordinal Example

What is your age?1 = under 182 = 18-223 = 22-304 = 30-405 = over 40

Ordinal Example

Overall, I am satisfied with myself 1) strongly disagree 2) disagree 3) neutral 4) agree 5) strongly agree

Interval

One unit on the scale represents the same magnitude on the trait or characteristic being measured across the whole range of the scale.

For example, if anxiety were measured on an interval scale, then a difference between a score of 10 and a score of 11 would represent the same difference in anxiety as would a difference between a score of 50 and a score of 51.

Rare to non-existent in behavioral research

Ratio

Have a true zero, so distance between points has meaning

Incorporate the properties of all other scales

What is your age?

Three Basic Types of Validity in Measurement

Table 7.2

A B

a b

Construct

MeasureConcurrent validity

Predictive validity

Reliability

Refers to the consistency and stability of a measurement scale.

Generally use a coefficient of reliability to assess the reliability of a measure.

Can range from 0 to 1.0, with 1.0 perfect reliability.

Guidelines for Minimum Reliabilities: 0.7 for exploratory research 0.8 for basic research 0.9 or better in applied settings where

important decisions will be made from scales

Methods for Reliability Assessment

1. Test-Retest Method

2. Alternative Forms

3. Internal Consistency

- Split-half

- Cronbach-Alpha/KR-20

Illustrations of Possible Reliability/Validity Situations in Measurement

Figure 7.3

Improving reliability

Write items that are unambiguousAdd more items of equal kind and quality

General rule of thumb is at least 3-4 items for any scale

Make the instructions clear and standard

Managerial Considerations(Why get involved?)

Bad measurement, no value to managers

Scaling sets limits on analysisGlobal and international research

compounds problemsMeasurement issues are early in

the business research process – compounds problems

Managerial Strategies for Ensuring Good Measurement

Require clearly defined constitutive concepts

Require operational definitionsRequire multi-item scales when possibleRequire validity, reliability and pretest

assessments when possibleRequire analytical foresight

Key Managerial Questions Pertaining to the Measurement Process

Exhibit 7.2