Measuring Social Life - City University of New York
Download
Report
Transcript Measuring Social Life - City University of New York
Measuring Social
Life
Ch. 5, pp. 112-137
1
Measuring Social Life
Connecting the specifics you observe in
the empirical world to an abstract idea you
cannot see directly
Inferring from this sample or measure to
an entire population or to abstract ideas
making
generalizations
2
WHY MEASURE?
Measurement transforms our ideas and
general observations into specific and
concrete data
Measuring helps communicate thoughts
and observations more effectively
3
MAKING ASPECTS OF THE
SOCIAL WORLD VISIBLE
Measurement extends the range of our
senses
Scientific
measurement produces a more
accurate measure than ordinary experience,
and it varies less with the specific observer
Measurement makes visible ideas that are
otherwise unseen
4
MEASURING with NUMBERS or
WORDS
In all research, data is collected systematically
Depending on whether data are quantitative or
qualitative, the process differs in 4 ways:
Timing
Direction
Data
form
Linkages
5
Two Parts of the Measurement
Process
All measurement builds on two processes:
conceptualization
operationalization
6
Conceptualization
conceptualization: "refining an idea by
giving it a very clear, explicit definition"
(117)
conceptual definition: "defining a variable
or concept in theoretical terms with
assumptions and references to other
concepts" (118)
7
Operationalization
operationalization: "the process of linking a
conceptual definition with a specific set of
measures" (117)
operational definition: "defining a concept
as specific operations or actions that you
carry out to measure it" (117)
8
Quantitative Conceptualization &
Operationalization
Measuring quantitative data flows in a 3-part
sequence
1.
2.
3.
conceptualization: think through the idea and create
a conceptual definition
operationalization: link the conceptual definition to
specific measurement procedures
measurement: apply the operational definition to
collect the data
9
The measurement process
connects three levels of reality,
from abstract to concrete:
conceptual, operational, and empirical
conceptual
hypothesis: stating a hypothesis
with the variables as abstract concepts
empirical hypothesis: the hypothesis stated in
terms of specific measures of variables
10
Racially biased policing:
determinants of citizen perception
Whether a person is a member of the dominant
or nondominant racial group
A person’s belief that the police are or are not
racially biased
Number and type of experiences with the local
police
Amount of exposure to media reports about
police actions of corruption or brutality
11
Fig. 5.1: Conceptualization & Operationalization: Abstract Construct to
Concrete Measure
Independent Variable
Dependent Variable
Hypothetical
Abstract Construct
Causal Relationship
Abstract Construct
theoretical
level
Conceptualization
Conceptualization
Conceptual Definition
Conceptual Definition
operational
level
Operationalization
Indicator or Measure
Operationalization
Tested Empirical
Hypothesis
Indicator or Measure
empirical
level
12
Qualitative Conceptualization and
Operationalization
In qualitative research, you use basic
working ideas during the data collection
process, rethinking old ideas and
developing new ideas based on
observations
Qualitative measurement is integrated with
other parts of a study
13
Naturalization of white culture?
naturalization means that a culture—a set
of values, outlooks, assumptions—is so
fully taken for granted that it becomes
invisible
white culture is a culture associated with
the white racial group
14
HOW TO CREATE GOOD
MEASURES: Reliability & Validity
reliability: a feature of measures—the
method of measuring is dependable and
consistent
validity: a feature of measures—the
concept of interest closely matches the
method used to measure it
you
are actually measuring what you say you
are measuring
15
Measurement validity is the fit between
conceptual & operational definitions
Three types of measurement validity
face
validity
content validity
criterion validity
16
Putting Reliability and Validity
Together
Reliability is a necessary but not sufficient
condition for validity
You can have a reliable measure that is
invalid
17
Levels of measurement
levels of measurement: the degree a
measure is refined or precise
the
way in which you conceptualize variable
limits the levels of measurement you can use
18
Continuous & discrete variables
continuous variable: a variable that can be
measured with numbers that can be subdivided
into smaller increments
has
an infinite # of values that flow along a continuum
discrete variable: a variable measured with a
limited number of fixed categories
has
a fixed set of separate values or categories,
instead of smooth continuum, discrete variables have
2 or more distinct categories
19
Levels of Measurement
Nominal measures only indicate a difference
among categories
Ordinal measures indicate a difference among
categories, and the categories can be order or
ranked
Interval measures do everything above, plus
specify the distance between categories
Ratio measures do everything all the other
levels do, plus they have true zero
20
Specialized Measures: Scales and
Indexes
scale: a measure that captures a
concept’s intensity, direction, or level at the
ordinal level measurement
index: a composite measure that
combines several indicators into a single
score
21
Mutually exclusive and exhaustive
attributes
mutually exclusive: each unit fits into
one, and only one, category of a variable
exhaustive: all units fit into some category
of a variable
22
Unidimensionality
unidimensionality: all items of an index
or scale measure the same concept or
have a common dimension
23
ADDING MEASURES TO GET A
SCORE: INDEX CONSTRUCTION
To create an index, you combine two or more
items into a single numerical score
examples:
FBI
crime index
consumer price index (CPI)
index of leading economic indicators
consumer confidence index (CCI)
(The Conference Board Consumer Confidence Index ®)
24
25
Two Complications in Index
Construction
Count items equally or weigh them?
1.
-
Unless you have a very good reason, it is usually best to
weight them equally
In a weighted index, you value or weigh items differently,
depending on your conceptualization, assumptions,
conceptual definition, or specialized statistical techniques
Missing data
2.
-
If data for one of your items (in a 4-item index) is missing for
some of your cases (e.g., in a societal development index,
literacy data is missing for 3 of 50 countries, you must decide
whether to drop the cases (3 countries) or substitute weaker
measures (using only 3 items in your index)
26
CAPTURING INTENSITY: SCALE
CONSTRUCTION
Most scales help us measure the intensity,
hardness or extremity of a person’s
feelings/opinion at the ordinal level
The simplest scale is a visual rating
e.g.,
a “feeling thermometer" is used to see
how people feel about various groups in
society, political candidates, public issues, etc.
27
Likert scale
The Likert scale offers a statement or questions,
and respondents indicate their response with a
set of answer choices, such as strongly agree,
agree, disagree, or strongly disagree, or:
- approve/disapprove of X
- support/oppose X
- believe X is always/never true
- do X frequently/rarely
28