Measurement Scales

Measurement Scales

This chapter covers procedures that will help students understand measurement scales so that they can select or design measures that are appropriate. The chapter focuses on measuring complex constructs like attitudes.

Understand...

* The nature of attitudes and their relationship to behavior.

* The critical decisions involved in selecting an appropriate measurement scale.

* The characteristics and use of rating, ranking, sorting, and other preference scales.

Scaling Process

Exhibit 12-1 illustrates where scaling fits into the research process.

An attitude is a learned, stable predisposition to respond to oneself, other persons, objects, or issues in a consistently favorable or unfavorable way.

* Attitudes can be expressed or based cognitively, affectively, and behaviorally. A example for each is provided in the slide.

* Business researchers treat attitudes as hypothetical constructs because of

* their complexity and

the fact that they are inferred from the measurement data, not actually observed.

Several factors have an effect on the applicability of attitudinal research for business.

* Specific attitudes are better predictors of behavior than general ones.

* Strong attitudes are better predictors of behavior than weak attitudes composed of little intensity or topic interest.

* Direct experiences with the attitude object produce behavior more reliably.

* Cognitive-based attitudes influence behaviors better than affective-based attitudes.

* Affective-based attitudes are often better predictors of consumption behaviors.

* Using multiple measurements of attitude or several behavioral assessments across time and environments improve prediction.

The influence of reference groups and the individual's inclination to conform to these influences improves the attitude-behavior linkage.

Measurement Scales

All survey questions must be actionable if you want results."

Frank Schmidt, senior scientist

The Gallup Organization

This note relates to the effort it takes to develop a good measurement scale, and that the emphasis is always on helping the manager make a better decision--actionable data.

Attitude scaling is the process of assessing an attitudinal disposition using a number that represents a person's score on an attitudinal continuum ranging from an extremely favorable disposition to an extremely unfavorable one.

* Scaling is the procedure for the assignment of numbers to a property of objects in order to impart some of the characteristics of numbers to the properties in question.

Selecting and constructing a measurement scale requires the consideration of several factors that influence the reliability, validity, and practicality of the scale. These factors are listed in the slide.

* Researchers face two types of scaling objectives: 1) to measure characteristics of the participants who participate in the study, and 2) to use participants as judges of the objects or indicants presented to them.

* Measurement scales fall into one of four general response types: rating, ranking, categorization, and sorting. These are discussed further on the following slide.

* Decisions about the choice of measurement scales are often made with regard to the data properties generated by each scale: nominal, ordinal, interval, and ratio.

* Measurement scales are either

* unidimensional or multidimensional,

* balanced or unbalanced,

* forced or unforced.

These characteristics are discussed further as is the issue of number of scale points and rater errors.

* Ranking scale constrain the study participant to making comparisons and determining order among two or more properties or objects. Participants may be asked to choose which one of a pair of cars has more attractive styling. A choice scale requires that participants choose one alternative over another. They could also be asked to rank-order the importance of comfort, ergonomics, performance, and price for the target vehicle.

* Categorization asks participants to put themselves or property indicants in groups or categories.

* Sorting requires that participants sort card into piles using criteria established by the researcher. The cards might contain photos or images or verbal statements of product features such as various descriptors of the car's performance.

* A rating scale is used when participants score an object or indicant without making a direct comparison to another object or attitude. For example, they may be asked to evaluate th e styling of a new car on a 7-point rating scale.

* With a unidimensional scale, one seeks to measure only one attribute of the participant or object. One measure of an actor's star power is his or her ability to "carry" a movie. It is a single dimension.

* A multidimensional scale recognizes that an object might be better described with several dimensions. The actor's star power variable might be better expressed by three distinct dimensions - ticket sales for the last three movies, speed of attracting financial resources, and column-inch/amount of TV coverage of the last three movies.

* A balanced rating scale has an equal number of categories above and below the midpoint.

* Scales can be balanced with or without a midpoint option.

* An unbalanced rating scale has an unequal number of favorable and unfavorable response choices.

* An unforced-choice rating scale provides participants with an opportunity to express no opinion when they are unable to make a choice among the alternatives offered.

* A forced-choice scale requires that participants select one of the offered alternatives.

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