Upload
dina-peters
View
215
Download
0
Tags:
Embed Size (px)
Citation preview
2
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 ideasmaking generalizations
3
WHY MEASURE?
Measurement transforms our ideas and general observations into specific and concrete data
Measuring helps communicate thoughts and observations more effectively
4
MAKING ASPECTS OF THE SOCIAL WORLD VISIBLE Measurement extends the range of our
sensesScientific 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
5
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
6
Two Parts of the Measurement Process All measurement builds on two processes:
conceptualization operationalization
7
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)
8
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)
9
Quantitative Conceptualization & Operationalization Measuring quantitative data flows in a 3-part
sequence1. conceptualization: think through the idea and create
a conceptual definition
2. operationalization: link the conceptual definition to specific measurement procedures
3. measurement: apply the operational definition to collect the data
10
The measurement process connects three levels of reality, from abstract to concrete:
conceptual, operational, and empiricalconceptual hypothesis: stating a hypothesis
with the variables as abstract conceptsempirical hypothesis: the hypothesis stated in
terms of specific measures of variables
11
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
12
Abstract Construct Abstract Construct
Conceptual Definition
Indicator or Measure
Conceptual Definition
Indicator or Measure
Independent Variable
Conceptualization
Operationalization
Dependent Variable
Conceptualization
Operationalization
Fig. 5.1: Conceptualization & Operationalization: Abstract Construct to Concrete Measure
Hypothetical
Causal Relationship
Tested Empirical Hypothesis
theoretical level
operational level
empiricallevel
13
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
14
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
15
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 ityou are actually measuring what you say you
are measuring
16
Measurement validity is the fit between conceptual & operational definitions
Three types of measurement validity face validitycontent validitycriterion validity
17
Putting Reliability and Validity Together Reliability is a necessary but not sufficient
condition for validity You can have a reliable measure that is
invalid
18
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
19
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
20
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
21
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
22
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
23
Unidimensionality
unidimensionality: all items of an index or scale measure the same concept or have a common dimension
24
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 ®)
26
Two Complications in Index Construction1. Count items equally or weigh them?
- 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
2. Missing data- 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)
27
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 ratinge.g., a “feeling thermometer" is used to see
how people feel about various groups in society, political candidates, public issues, etc.
28
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