Lecture Chapter 04

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Chapter 4
Conceptualization and
Measurement
Introduction
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IF IT EXISTS ---- IT CAN BE MEASURED
Measurement is used to gain mathematical
insight into our data.
When we measure we can compare our data to
a standard used for evaluation
Through measurement we can inspect, analyze
and interpret our information
Measurement is essential to Quantitative
research
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Conceptualization. The process of
specifying what we mean by a term.
A concept is a mental image that
summarizes a set of similar
observations,feelings or ideas.
Some concepts are more abstract than
others
Introduction, cont.
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Concepts like “social health,” “prejudice,” and
even “binge drinking” require an explicit definition
before they are used in research because we
cannot be certain that all readers will share a
particular definition or that the current meaning of
the concept is the same as it was when previous
research was published.
It is especially important to define clearly concepts
that are abstract or unfamiliar.
When we refer to concepts like “social control,”
“anomie,” or “social health,” we cannot count on
others knowing exactly what we mean.
Conceptualization in Practice
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If we are to do an adequate job of
conceptualizing, we must do more than just
think up some definition, any definition, for our
concepts (Goertz 2006).
We have to turn to social theory and prior
research to review appropriate definitions.
We should understand how the definition we
choose fits within the theoretical framework
guiding the research and what assumptions
underlie this framework.
Conceptualization in Practice, cont.
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Example: Do you have a clear image in mind when
you hear the term youth gangs?
“Neither gang researchers nor law enforcement
agencies can agree on a common definition . . . and
a concerted national effort . . .failed to reach a
consensus” (Howell 2003:75).
If you use the term you must have a clear definition
of how you are using it.
Conceptualization in Practice, cont.
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Decisions about how to define a concept reflect
the theoretical framework that guides the
researchers.
For example, the concept “poverty” has always
been somewhat controversial, because different
conceptualizations of poverty lead to different
estimates of its prevalence and different social
policies for responding to it.
Conceptualization is specifying the dimensions
of and defining the meaning of the concept
Variables
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A variable is any observation that can
take different values
Gender, Age, Religion, Ethnicity are
variables
Variables have attributes or values
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Attributes (Values) of Gender are:
1. Male 2. Female
The main concept in a question on a
questionnaire is the variable being
measured.
Did you vote in the last election.
The main concept is Vote.
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An indicator is the response to a single
question
Variable Vote (Did you vote?)
Indicator = your answer - Yes
The values or attributes of the variable
vote are: 1. Yes, voted or 2. No, didn’t
vote.
From Concepts to Observations,
cont.
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Operationalization is the process of connecting
concepts to observations. It is the process of
choosing the variable to represent the concept.
You can think of it as the empirical counterpart of
the process of conceptualization.
When we conceptualize, we specify what we mean
by a term.
Example: “Race” is an important concept in social
research, but we know it is a social construct and
not based on any biological reality. What people
mean by “race” has varied over time and from
place to place. The term Race is often confused
with Ethnicity.
From Concrete to Abstract
Concepts
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Concepts vary in their level of abstraction, and
this, in turn, affects how readily we can specify
the indicators pertaining to the concept.
Would you now consider “race” to be an
abstract or a concrete concept?
A very abstract concept like social status may
have a clear role in social theory but a variety of
meanings in different social settings.
We often use abstract concepts in our theories:
crime, abuse, deterrence, substance abuse
From Concrete to Abstract
Concepts, cont.
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Usually, the term variable is used to refer to
some specific aspect of a concept that varies,
and for which we then have to select even more
concrete indicators.
The important thing to keep in mind is that we
need to define clearly the concepts we use and
then develop specific procedures for measuring
variation in the variables related to these
concepts.
Measurement Operations
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The deductive researcher proceeds from
defining concepts in the abstract
(conceptualizing) to identifying variables to
measure, and finally to developing specific
measurement procedures.
We use variables which are derived from
concepts in our hypotheses and research
questions?
PROCESS
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Theory – Punishment deters crime
We can define the concept crime with
the variable ‘physical spousal abuse’
We can define the concept punishment
with the variable ‘arrest’
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Will arresting physical abusers of
spouses deter repetition of the
offense? (Research Question)
If spousal abusers are arrested on 1st
offense then recidivism (repeating
offense) will be reduced (Hypothesis)
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Some concepts are more concrete
than abstract i.e. Age – time elapsed
since birth
But we may have a different meaning
in mind – How old in hours, month,
years
How we will use the variable is
important in defining it
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Sometimes we may have to use
qualitative means to define a concept.
Instead of using a scientific meaning of
‘diversity’ we may want to use the
general public’s meaning of diversity
for our research or we may want to
know the difference in the meaning of
rape for women versus men
Available versus Empirical Data
Where does our data come from?
PRIMARY OR EMPIRICAL DATA – Collected
by the researcher (not from library research)
AVAILABLE OR SECONDARY DATA
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Government reports are rich and readily
accessible sources of social science data.
Organizations ranging from nonprofit service
groups to private businesses also compile a
wealth of figures that may be available to some
social scientists for some purposes.
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In addition, the data collected in many
social science surveys are archived
and made available for researchers
who were not involved in the original
survey project.
Using Available Data, cont.
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Before we assume that available data will be useful,
we must consider how appropriate they are for our
concepts of interest.
We may conclude that some other measure would
provide a better fit with a concept or that a particular
concept simply cannot adequately be
operationalized with the available data.
We also cannot assume that available data are
accurate, even when they appear to measure the
concept in which we are interested in a way that is
consistent across communities.
Using Available Data, cont.
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Government statistics that are generated
through a central agency like the U.S. Bureau
of the Census are often of high quality, but
caution is warranted when using official data
collected by local levels of government.
Constructing Questions
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Asking people questions is the most common and
probably the most versatile operation for measuring
social variables. i.e. survey research (Quantitative)
Most concepts about individuals can be defined in
such a way that measurement with one or more
questions becomes an option.
Of course, in spite of the fact that questions are, in
principle, a straightforward and efficient means to
measure individual characteristics, facts about
events, level of knowledge, and opinions of any
sort, can easily result in misleading or inappropriate
answers.
Constructing Questions, cont.
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Memories and perceptions of the events about
which we might like to ask can be limited, and some
respondents may intentionally give misleading
answers.
For these reasons, all questions proposed for a
study must be screened carefully for their
adherence to basic guidelines and then tested and
revised until the researcher feels some confidence
that they will be clear to the intended respondents
and likely to measure the intended concept (Fowler
1995).
Alternative measurement approaches will be
needed when such confidence cannot be achieved.
Types of Questions Used in
Social Research
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Measuring variables with single questions is
very popular.
Public opinion polls based on answers to single
questions are reported frequently in newspaper
articles and TV newscasts.
Single questions can be designed with or
without explicit response choices.
o
o
closed-ended (fixed-choice) question
open-ended questions
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Closed Ended –survey provides
preformatted response categories for
the subject to circle or check
Closed ended: What is your Ethnicity?
1. Anglo 2.Hispanic 3. African
American 4. Asian, 5 Native American
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Open-ended: respondent replies in his
or her own words either by writing or
talking
Open ended: How would you describe
your ethnic background?
Making Observations-qualitative
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Observations can be used to measure
characteristics of individuals, events, and
places.
The observations may be the primary form of
measurement in a study, or they may
supplement measures obtained through
questioning.
Direct observations can be used as indicators
of some concepts.
Observations may also supplement data
collected in an interview study.
Collecting Unobtrusive Measures
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Qualitative
Unobtrusive measures allow us to collect data about
individuals or groups without their direct knowledge or
participation. (Can be qualitative or quantitative)
Eugene Webb and his colleagues (2000) identified four
types of unobtrusive measures: physical trace evidence,
archives (available data), simple observation, and
contrived observation (using hidden recording hardware
or manipulation to elicit a response).
Unobtrusive measures can also be created from such
diverse forms of media as newspaper archives or
magazine articles, TV or radio talk shows, legal
opinions, historical documents, personal letters, or
e-mail messages.
Combining Measurement
Operations
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Using available data, asking questions, making
observations, and using unobtrusive indicators
are interrelated measurement tools, each of
which may include or be supplemented by the
others.
Researchers may use insights gleaned from
questioning participants to make sense of the
social interaction they have observed.
Unobtrusive indicators can be used to evaluate
the honesty of survey responses.
Combining Measurement
Operations, cont.
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The choice of a particular measurement method is
often determined by available resources and
opportunities, but measurement is improved if this
choice also takes into account the particular
concept or concepts to be measured.
Questioning can be a particularly poor approach for
measuring behaviors that are very socially
desirable, such as voting or attending church, or
that are socially stigmatized or illegal, such as
abusing alcohol or drugs.
People have the tendency to answer questions in
socially approved ways.
Exhibit 4.9
Triangulation
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Triangulation—the use of two or more different
measures of the same variable—can
strengthen measurement considerably.
When we achieve similar results with different
measures of the same variable, particularly
when they are based on such different methods
as survey questions and field-based
observations, we can be more confident in the
validity of each measure.
Levels of Measurement
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When we know a variable’s level of measurement,
we can better understand how cases vary on that
variable and so understand more fully what we
have measured.
Level of measurement: The mathematical
precision with which the values of a variable can be
expressed. (has implications for the type of
statistics to be used)
The nominal level of measurement, which is
qualitative, has no mathematical interpretation; the
quantitative levels of measurement— ordinal,
interval, and ratio—are progressively more precise
mathematically.
Nominal Level of Measurement
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The nominal level of measurement identifies
variables whose values have no mathematical
interpretation; they vary in kind or quality but
not in amount (they may also be called
categorical or qualitative variables).
Gender is a nominal variable.
Nationality, occupation, religious affiliation, and
region of the country are also measured at the
nominal level.
Nominal Level of Measurement,
cont.
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Although the attributes of categorical variables do
not have a mathematical meaning, they must be
assigned to cases with great care. The attributes
we use to measure, or categorize, cases must be
mutually exclusive and exhaustive:
A variable’s attributes or values are mutually
exhaustive if every case has at least one attribute.
i.e. Religion: 1.Catholic, 2. Jewish, 3.Protestant, 4.
Other
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The different values of a variable
measured at the ordinal level must
also be mutually exclusive and
exhaustive.
variable’s attributes are exclusive
when every case can be classified into
only one of the categories.
Grouped Age: 1.0-20, 2. 21-30, 3. 3140 etc.
Ordinal Level of Measurement
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The first of the three quantitative levels is the
ordinal level of measurement.
At this level, the numbers assigned to cases specify
only the order of the cases, permitting “greater
than” and “less than” distinctions. i.e. Heat= 1. low,
2. medium, 3. high
Or, if the response choices to a question range from
“very wrong” to “not wrong at all”, for example.
(Some researchers use this type of ordinal level
data as Interval, i.e. Likert Scales)
Ordinal Level of Measurement,
cont.
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Of course, an ordinal rating scheme assumes
that respondents have similar interpretations of
the terms used to designate the ordered
responses.
This is not always the case, because rankings
tend to reflect the range of alternatives with
which respondents are familiar. Ugly, Ordinary,
Pretty (inbalance in the terms used)
Interval Level of Measurement
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The numbers indicating the values of a variable at
the interval level of measurement represent fixed
measurement units but have no absolute, or fixed,
zero point.
The numbers can therefore be added and
subtracted, but ratios are not meaningful.
Again, the values must be mutually exclusive and
exhaustive.
This level of measurement is represented by the
difference between two Fahrenheit temperatures.
We assume equal intervals between attributes.
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60 degrees may be 30 degrees hotter
than 30 degrees, but 60 degrees
cannot be said to be twice as hot as 30
degrees because there is no absolute
zero to set up a ratio relationship
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There are very few true interval-level
measures in social science.
Interval assumes equal distance
between attributes
Can’t say between low, medium, high
there is equal distance but some use
Likert construction as such
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Likert Scale
1. Very satisfied 2. Satisfied 3.
dissatisfied 4. very dissatisfied
Notice there is no middle ground i.e.
1. Very satisfied 2. Satisfied
3.satisfied/dissatisfied 4. dissatisfied 5.
Very dissatisfied
Ratio Level of Measurement
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The numbers indicating the values of a variable at
the ratio level of measurement represent fixed
measuring units and an absolute zero point (zero
means absolutely no amount of whatever the
variable indicates). i.e. Age is continuous (numbers
indicating values are points on a continuum
For most statistical analyses in social science
research, the interval and ratio levels of
measurement can be treated as equivalent.
On a ratio scale, 10 is 2 points higher than 8 and is
also 2 times greater than 5—the numbers can be
compared in a ratio.
Ratio Level of Measurement, cont.
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Of course, the numbers also are mutually
exclusive and exhaustive, so that every case
can be assigned one and only one value.
Age is ratio:Ages range in order from 0 to 100
Test scores range in order from 0 to 100
Also people’s ages can be represented by
values ranging from 0 years (or some fraction of
a year) to 120 or more. A person who is 30
years old is 15 years older than someone who
is 15 years old (30 - 15 = 15) and is twice as old
as that person (30/15 = 2).
Comparison of Levels of
Measurement
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Researchers choose levels of measurement in
the process of operationalizing variables; the
level of measurement is not inherent in the
variable itself. Many variables can be measured
at different levels, with different procedures.
It is usually is a good idea to try to measure
variables at the highest level of measurement
possible. The more information available, the
more ways we have to compare cases.
Measurement Validity
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Measurement validity refers to the extent to
which measures indicate what they are
intended to measure.
When a measure “misses the mark”—when it
is not valid—our measurement procedure has
been affected by measurement error.
Measurement error can arise in three general
ways.
Measurement Validity, cont.
1.
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Idiosyncratic individual errors are errors
that affect a relatively small number of
individuals in unique ways that are unlikely to
be repeated in just the same way.
Example: Individuals make idiosyncratic
errors when they don’t understand a question,
when some unique feelings are triggered by
the wording of question, or when they are
feeling out of sorts due to some recent events.
Measurement Validity, cont.
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Generic individual errors occur when the
responses of groups of individuals are affected
by factors that are not “what the instrument is
intended to measure.”
For example, individuals who like to please
others by giving socially desirable responses
may have a tendency to say that they “agree”
with statements, simply because they try to
avoid saying they “disagree” with anyone.
Measurement Validity, cont.
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Method factors can also create errors in the
responses of most or all respondents. Questions
that are unclear may be misinterpreted by most
respondents, while unbalanced response choices
may lead most respondents to give positive rather
than negative responses.
For example, if respondents are asked a question
with unbalanced response choices, they are more
likely to respond that something is wrong than if
they are asked the question with the balanced
response choices.
Reliability
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Reliability means that a measurement procedure
yields consistent scores when the phenomenon
being measured is not changing (or that the
measured scores change in direct correspondence
to actual changes in the phenomenon).
If a measure is reliable, it is affected less by random
error, or chance variation, than if it is unreliable.
Reliability is a prerequisite for measurement
validity: We cannot really measure a phenomenon if
the measure we are using gives inconsistent
results.
Ways to Improve Reliability and
Validity
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Whatever the concept measured or the
validation method used, no measure is without
some error, nor can we expect it to be valid for
all times and places.
Remember that a reliable measure is not
necessarily a valid measure.
Unfortunately, many measures are judged to be
worthwhile on the basis of only a reliability test.
Conclusions, cont.
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Statistical tests can help to determine whether a given
measure is valid after data have been collected, but if it
appears after the fact that a measure is invalid, little can
be done to correct the situation, so do pretests.
If you cannot tell how key concepts were operationalized
when you read a research report, don’t trust the findings.
And if a researcher does not indicate the results of tests
used to establish the reliability and validity of key
measures, remain skeptical.
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