Babbie Chapter5

7/23/2019 Babbie Chapter5

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Chapter 5

Conceptualization,Operationalization, and

Measurement


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Chapter Outline

Introduction

Measuring Anything That Exists

Conceptualization Definitions in Descriptive and Explanatory

Studies

Operationalization Choices Criteria of Measurement Quality

A Quandary Revisited


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Measurement

Careful, deliberate observations of the

real world for the purpose of describing

objects and events in terms of theattributes composing a variable.

More precisely, measurement is the

process of assigning numbers of labels tounits of analysis in order to represent

conceptual properties


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The entire measurement process consists

of moving from the abstract (concepts) to

the concrete (measures of concepts)


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Conceptualization

Process of specifying what we mean

when we use particular terms.

Produces an agreed upon meaning for aconcept for the purposes of research.

Describes the indicators we'll use to

measure the concept and the differentaspects of the concept.


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Indicators and Dimensions

An indicatoris a sign of the presence or

absence of the concept were studying.

Dimension is a specifiable aspect of aconcept.

Religiosity might be specified in terms of

a belief dimension, a ritual dimension, adevotional dimension, a knowledge

dimension, and so forth.


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Interchangeability of

Indicators

If several different indicators all represent thesame concept, all of them will behave the sameway the concept would behave if it were real

and could be observed. If women are more compassionate, we should

be able to observe that using a reasonablemeasure of compassion.

If women are more compassionate only onsome indicators, we should see if the indicatorsrepresent different dimensions of compassion.


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Specification of Concepts

The specification of concepts in scientific inquiry

depends on nominal and operational definitions.

A nominal definition is simply assigned to aterm without any claim that the definition

represents a real entity.

An operational definition specifies precisely

how a concept will be measuredthat is, theoperations well perform.


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Definitions

Real - mistakes a construct for a real

entity.

Nominal - assigned to a term without aclaim that the definition represents a

"real" entity.

Operational definitions - Specifies howa concept will be measured.


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From Concept to

Measurement

Progression from what a term means to

measurement in a scientific study:

Conceptualization Nominal Definition

Operational Definition

Measurements in the Real World


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Operational definitions

These are never perfect

Comprised of one or more indicators

They represent the researchers bestattempt at capturing the concept in

question

Religiosity example


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Nominal Measure

A level of measurement describing a

variable that has attributes that are merely

different, as distinguished from ordinal,interval, or ratio measures.

Gender is an example of a nominal

measure.


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Ordinal Measure


variable with attributes we can rank-order

along some dimension. An example is socioeconomic status as

composed of the attributes high, medium,

low.


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Interval Measures


variable whose attributes are rank-

ordered and have equal distancesbetween adjacent attributes.


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Ratio Measures


variable with attributes that have all the

qualities of nominal, ordinal, and intervalmeasures and in addition are based on a

true zero point.


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Kaplans Classes

Things Scientists Measure

Direct observables - things that can be

observed simply and directly. Indirect observables - things that require

more subtle observations.

Constructs - based on observations thatcannot be observed.


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Measurement Quality

Precision and accuracy

Reliability

Validity


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Reliability

That quality of measurement method that

suggests that the same data would have been

collected each time in repeated observations of

the same phenomenon.

In the context of a survey, we would expect that

the question Did you attend religious services

last week? would have higher reliability thanthe question About how many times have you

attended religious services in your life?


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Tests for Checking Reliability

Test-retest method - take the same

measurement more than once.

Split-half method - make more than onemeasurement of a social concept

(prejudice).

Use established measures. Check reliability of research-workers.


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Validity

A term describing a measure that accuratelyreflects the concept it is intended to measure.

Example: IQ would seem a more validmeasure of intelligence than the number ofhours spent in the library.

Though the ultimate validity of a measure cannever be proved, we may agree to its relativevalidity on the basis of face validity, criterionvalidity, content validity, construct validity,internal validation, and external validation.


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Face Validity

That quality of an indicator that makes it

seem a reasonable measure of some

variable. That the frequency of attendance at

religious services is some indication of a

persons religiosity seems to make sensewithout a lot of explanation.


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Construct and Content

Validity

Construct Validity

The degree to which a measure relates

to other variables as expected within asystem of theoretical relationships.

Content Validity

Refers to how much a measure coversthe range of meanings included within aconcept.


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An Analogy to Validity and

Reliability

A good measurement technique should be both valid

(measuring what it is intended to measure) and reliable

(yielding a given measurement dependably).

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