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Chapter Nine

Measurement & Scaling

Copyright © Houghton Mifflin Company. All rights reserved. 9 | 2

Chapter Objectives

• Identify the four levels of measurement under which numbers generated through a survey can be classified.

• Distinguish among attributes, behavioral variables, beliefs, and attitudes.

• List and describe five methods for inferring people's attitudes.


Chapter Objectives (Cont’d)

• Discuss the various dimensions on which rating scales can vary.

• Apply the formats of Likert, semantic-differential, and Stapel scales and discuss how data generated by these scales are analyzed and interpreted.

• Define validity, reliability, and sensitivity of a scale.


Harris Interactive:U.S.Based Survey

Reputation Score of Top Ten Corporations


Reputation

Workplace Environment

Products andServices

Emotional Appeal

Financial Performance

Social Responsibility

Vision and Leadership

Harris Interactive: U.S. Based Survey Six Dimensions of Reputation


20 Attributes of the Six Dimensions Measured Using a 7 Point Scale

• Emotional Appeal– Like

– Respect

– Trust

• Workplace Environment– Well managed

– Appealing workplace

– Employee Talent


20 Attributes of the Six Dimensions Measured Using a 7 Point Scale (Cont’d)

• Products and Services– Innovative– Strong brand– Quality– Value

• Social Responsibility– Citizenship– Environmental stewardship– Ethics


Six Dimensions and Its Scales

• Vision and Leadership– Clear values– Strong leadership– Inspiring vision

• Financial Performance– Growth prospects– Past results– Recognizes opportunities– Low risk


Measurement

• Measurement is “the assignment of numbers to observations [or responses] according to some set of rules”


Measurement Levels

• Nominal• Ordinal • Interval• Ratio


Nominal-Scaled Responses

• Numbers forming a nominal scale are no more than labels used solely to identify different categories of responses

• Example: What is your sex?– Male

– Female


Nominal-Scaled Responses (Cont’d)

• Which one of the following media influences your purchasing decisions the most? – Television – Radio– Newspapers – Magazines– Internet


Central Tendency– Mode

• The mode is the most frequent category - only statistics applicable to nominal variable


Ordinal-Scaled Responses

• An ordinal scale is more powerful than a nominal scale in that the numbers possess the property of rank order

• How long do you spend reading newspapers on a typical weekday?– Less than 5 minutes– 5 minutes to less than 15 minutes– 15 minutes to less than 30 minutes– 30 minutes or more


Mode and Median

• The mode and the median are the most meaningful measures of central tendency for ordinal-scaled responses

• Median – the category in which the 50th percentile response falls when all responses are arranged from lowest to highest (or vice versa)


Response Category Percentage of Respondents Checking Category

1 40

2 25

3 25

4 10

Consider the following distribution of responses to the question about reading newspapers

• In this case, the mode is category 1, and the median is category 2.


Interval-Scaled Responses

• An interval scale has all the properties of an ordinal scale and the differences between the scale values can be meaningfully interpreted


Interval-Scaled Responses (Cont’d)

(Please check the most appropriate category.) Will definitely not buy _____

(1)

Extremely unlikely _____

(2)Unlikely _____

(3)

Likely _____

(4)Extremely likely _____

(5)

Will definitely buy _____

(6)

• How likely are you to buy a new automobile within the next six months?


Exhibit 9.1 Impact of Arbitrariness of an Interval Scale’s Starting Point


Ratio-Scaled Responses

• Ratio scales possess all the properties of an interval scale and the ratios of numbers on these scales have meaningful interpretations

• What is your annual income before taxes? $______

• How far is your workplace from your home? _____ miles


Classes of Variables

• Attributes• Behavior• Beliefs• Attitudes


Attitudes

• Attitudes are similar to beliefs, except that they also involve respondents’ evaluative judgments

• For instance, do respondents feel print advertisements for cigarettes should be banned?


Attitudes –Conceptually and Operationally

• A conceptual definition of attitude may be “a predisposition to respond favorably or unfavorably to a stimulus object”

• An operational definition of attitude refers to a person’s attitude towards a particular retail store that may be measured as the total of the person’s expressed degree of agreement, on a 5-point, “strongly agree” to “strongly disagree” scale, with each of a set of 20 evaluative statements about various aspects of the retail store


Attitude Scaling

• Attitudes – Widely believed to be a key determinant of behavior

– Can only be inferred and cannot be directly ascertained

• Measures in which inferences are drawn from – Observed overt behavior

– Individual's reaction

– Performance on objective tasks

– Physiological reactions


Observing Overt Behavior

• Observation of overt behavior is useful when other attitude measurement methods are inconvenient or infeasible

• An observation study can be used to ascertain the attitudes of very young children toward a variety of toys


Analyzing Reactions to Partially Structured Stimuli

• Projective Techniques– The approach of analyzing reactions to

partially structured stimuli involves asking respondents to react to or describe in some fashion, an incomplete, vague stimulus


Evaluating Performance on Objective Tasks

• To evaluate performance on objective tasks, respondents are asked to complete an ostensibly objective, well-defined task

• The nature of their performance is then analyzed to infer their attitudes


Monitoring Physiological Responses

• Monitoring physiological responses is based on the premise that a person's emotional reactions to a stimulus will be accompanied by corresponding involuntary physiological changes


Self-report Measurements of Attitudes

• This method involves asking respondents relatively direct questions concerning attitudes toward whatever is of interest to the researcher

• The questions are typically in the form of rating scales on which respondents check off appropriate positions that best reflect their feelings


VeryBad

VeryGood

Graphic Formats

• A graphic rating scale presents a continuum, in the form of a straight line, along which a theoretically infinite number of ratings are possible

• Example: Indicate your overall opinion about eBay by placing a mark at an appropriate position on the line below.


Itemized Formats

• Itemized rating scales have a set of distinct response categories

• Any suggestion of an attitude continuum underlying the categories is implicit

• They essentially take the form of the multiple-category questions


Comparative Assessments

• Comparative Rating Scale– Provides all respondents with a common

frame of reference

– Allows the researcher to be confident that all respondents are answering the same question


Non-comparative Assessments

• Non-comparative Rating Scale– Implicitly permits respondents to use any

frame of reference or no frame of reference at all


Forced Response Choices

• A forced-choice scale does not give respondents the option of expressing a neutral or middle-ground attitude


Indicate your overall opinion about eBay by checking one of the following categories:

Very Neither Bad VeryBad Bad nor Good Good Good[ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] 1 2 3 4 5 6 7 8 9

What is your overall rating of eBay in comparison with other auction sites?

Much worse Worse About the same Better Much better ( ) ( ) ( ) ( ) ( )

Forced Response Choices (Cont’d)


Non-forced Response Choices

• A non-forced-choice scale give respondents the option to express a neutral attitude


Indicate your overall opinion about eBay by placing a

mark in the category that best summarizes your feelings.

Very VeryBad Good[ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] 1 2 3 4 5 6 7 8 9


Much worse Worse Better Much better ( ) ( ) ( ) ( )

Non-forced Response Choices (Cont’d)


Balanced Response Choices

• A balanced scale is one that has an equal number of positive/favorable and negative/unfavorable response choices


Indicate your overall opinion about eBay by checking one of the following categories:

Very Neither Bad VeryBad Bad nor Good Good Good[ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] [ ] 1 2 3 4 5 6 7 8 9


Much worse Worse About the same Better Much better ( ) ( ) ( ) ( ) ( )

Balanced Response Choices (Cont’d)


Unbalanced Response Choices

• An unbalanced rating scale that can be used if respondents’ opinions about a subject are anticipated to be predominantly positive


Labeled Response Choices


Unlabeled Response Choices


Exhibit 9.2 Rating Scales with Picture Labels


Number of Scale Positions

• A scale with a large number of positions will not be meaningful if respondents are unable to make fine mental distinctions with respect to whatever is being measured

• More precise measurements should result as the number of scale positions increase


Paired Comparison Scale

• In each of the following pairs, which store do you think is better?

(please check one online auction site within each pair)

_______ Amazon or _______ eBay

_______ eBay or _______ Yahoo! Auction

_______ PriceLine.com or _______ eBay

_______ eBay or _______ Ubid.com


Commonly Used Multiple-item Scales

• Likert Scale• Semantic-Differential Scale• Stapel Scale


6.

5.

4.

3.

2.

1.

________________________________________The auction site support system is confusing

________________________________________The auction site is notcareful with personal information

________________________________________The auction site responds to complaints quickly

________

________

________

Agree

________

________

________

StronglyAgree

________________________The auction site commission is reasonable

________________________User registrationis complex at this site

________________________The online auction site contains an abundance of exhibits

Neither Agree nor Disagree

Disagree Strongly Disagree

Table 9.2 Likert Scale Items


Exhibit 9.3 Semantic-Differential Scale Items


Exhibit 9.4 Pictorial Profiles Based on Semantic-Differential Ratings


-5-5-5-5-5-5

-4-4-4-4-4-4

-3-3-3-3-3-3

-2-2-2-2-2-2

-1-1-1-1-1-1

+1+1+1+1+1+1

+2+2+2+2+2+2

+3+3+3+3+3+3

+4+4+4+4+4+4

+5+5+5+5+5+5

Confusing Support System

Poor Protection of Personal Information

Good Response

to Complaints

Low Commission

Complex User

Registration

Abundance of

Exhibits

Table 9.3 Stapel Scale


Strengths Of Multiple-Item Scales

• Validity• Content validity• Construct validity• Predictive validity

• Reliability• Test-retest reliability• Split-half reliability

• Sensitivity


Validity

• The validity of a scale is the extent to which it is a true reflection of the underlying variable it is attempting to measure


Content Validity

• Face validity or content validity is the extent to which the content of a measurement scale seems to tap all relevant facets of an issue that can influence respondents’ attitudes


Exhibit 9.5 Types of Equivalence


Construct Validity

• Construct Validity is the nature of the underlying variable or construct measured by the scale


Predictive Validity

• Predictive Validity refers to how well the attitude measure provided by the scale predicts some other variable or characteristic


Reliability

• Reliability measures how consistent or stable the ratings generated by the scale are likely to be


Test-Retest Reliability

• Test-Retest Reliability measures the stability of ratings over time and involves administering the scale to the same group of respondents at two different times


Split-Half Reliability

• Split-Half Reliability measures the degree of consistency across items within a scale and can only be assessed for multiple-item scales


Sensitivity

• Sensitivity focuses specifically on its ability to detect subtle differences in the attitudes being measured

powerpoint

Documents

balanced response

forced response

a7 point scale

monitoring

comparative

auction sites

comparative

half reliability