04/18/23Marketing Research 1

An attempt to provide an objective

estimate of a natural phenomenon

◦ e.g. measuring height

◦ or weight

04/18/23Marketing Research 2

Nominal Scales ◦ Categories -- mutually exclusive and collectively exclusive.

Ordinal Scales ◦ Rank order – e.g. most important to least important.

Interval Scales ◦ Ordinal + the intervals between data points are equal.

Ratio Scales ◦ Above + a meaningful absolute zero or origin.

04/18/23Marketing Research 3

How could you measure height using the following levels of measurement?

◦ Nominal Scales

◦ Ordinal Scales

◦ Interval Scales

◦ Ratio Scales

04/18/23Marketing Research 4

Evaluate my bathroom scale:

Is it ACCURATE?

04/18/23Marketing Research 5

Consistent results over time.

Measures are free from random error.

Test-Retest Reliability:

Obtained by repeating the measurement

using the same instrument under as nearly

the same conditions as possible.

04/18/23Marketing Research 6

Addresses the issue of whether what we tried

to measure was actually measured.

How do I know if my bathroom scale is valid?

That is, does 160 really MEAN anything?

How could I know this with my bathroom scale?

1. JUST using the same scale

2. Using ANOTHER scale.

04/18/23Marketing Research 7

• Face validity

• Content validity

• Criterion-Related Validity

• Predictive Validity

• Concurrent Validity

• Construct Validity

• Convergent Validity

• Discriminant Validity

All types of validity are related.

04/18/23Marketing Research 8

• Situation 1: A lack of reliability

• my scale varies a lot (150, 160, 170)

• Situation 2: High reliability, but lacks validity

• My scale always shows 160, but other scales are different

• Situation 3: Reliable, consistent, and valid

• ALL scales show a consistent 160

04/18/23Marketing Research 9

Scaling Defined

In order to decrease noise:

you measure something several times

• Unidimensional scaling

• Multidimensional scaling

Graphic Rating Scales

Present to respondents with a graphic continuum

typically anchored by two extremes

04/18/23Marketing Research 10