chapter 4: conceptualization and measurement. measuring anything that exists measurement –...
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Chapter 4: Conceptualization and Measurement
Measuring Anything that Exists
Measurement – Careful, deliberate observations of the real world
For the purpose of describing objects and events in terms of the
Attributes composing the variable
Conceptualization
Process: Of specifying what we mean when we use particular terms in research.
Conceptualization process creates an agreed-on meaning for a concept
For the purposes of research
Conceptions, Concepts, and Reality
Conceptualization – The mental process whereby fuzzy and imprecise notions (concepts) are made more specific and precise.
How would you conceptualize…Prejudice?
Compassionate?
Concepts
• Mental representations
• Typically based on experience • Concepts can be of real phenomena• Dogs, Clouds, Pain, Cars, Cell phones
• Concepts can be of agree-upon phenomena• Truth, Beauty, Justice, Prejudice, Value,
Concepts as Constructs
Concepts are constructs derived by mutual agreement from mental images.
Conceptions summarize collections of seemingly related observations and experiences.
Things that can be Measured
Three classes of things can be measured
1. Direct Observables
2. Indirect Observables
3. Constructs
Things that can be Measured
• Three classes of things can be measured•
1. Direct observables Height, weight, color, etc.
2. Indirect observables Questionnaires Information on Gender, age, income, etc.
Things that can be Measured
3. Constructs
Theoretical creations based on observations
Cannot be seen either directly or indirectly, such as:
IQ Leisure Satisfaction Environmental Values
Indicators and Dimensions
Indicator Concept or direct observable used
to measure a construct.
For example, consider a person’s extent of agreement with this statement:
“I am a person of worth”
As an indicator of person’s self-esteem
Indicators
Rosenberg’s self-esteem scale contains ten statements used to measure self-esteem.
Each statement assumed to accurately measure self-esteem as an indicator of it.
Indicators
Rosenberg’s self-esteem scale contains ten statements used to measure self-esteem.
Each statement assumed to accurately measure self-esteem as an indicator of it.
(Handout)
Gallup Index of Leading Religious Indicators
1. Believe in God
2. Religious preference
3. Member of a church
4. Attended church last 7 days
5. Religion very important in life
6. Religion answers problems
7. High confidence in organized religion
8. Give high ratings to ethical standards of clergy
Indicators: How would you measure…
Political party affiliation?
Age?
Grade point average?
Satisfaction with college?
Religious affiliation?
Dimensions
Constructs sometimes have multiple dimensions, each with indicators.
For example: The construct Locus-of-Control
Three dimensions: Internal External Powerful others
1/27 Identify Indicators & Dimensions
Identify appropriate indicators and dimensions for…
College success
Political activity
Poverty
Binge drinking
Fear of crime
Nominal, and Operational Definitions
Nominal definition: Assigned to a term without any claim that the definition represents a “real” entity. Name
Operational definition: Specifies precisely how a concept will be measured
Levels of Measurement
• Level of Measurement=Mathematical precision with which values of a variable can be expressed.
• Nominal level of measurement:
• Qualitative
• No mathematical interpretation
Levels of Measurement
Quantitative levels of measurement:
Ordinal
Interval
Ratio
Progressively more precise mathematically
Nominal Measures (Labels)
Identifies variables whose values have no mathematical interpretation
Categories are not ordered
If only two categories: Referred to as a dichotomous or “Dummy” variable
Examples of Nominal Measures
Ordinal Measures
Categorical--Some categories are higher than others.
For example: Income tax brackets Social class Levels of education
Ordinal Measures
Cannot measure the distance between categories Only which is higher or lower
Cannot say that someone is twice as educated as
someone else
Can be used as a dependent variable
Example: Ordinal Measures
When attributes can be rank-ordered… Distances between attributes do not have any meaning For example : code Educational Attainment as
0=less than H.S.
1=some H.S.
2=H.S. degree
3=some college
4=college degree
5=post college
Is the distance from 0 to 1 the same as 3 to 4?
Example: Ordinal Measures
Interval Measures
Called scalar or index variables
Provide scale or index to measure between levels
Can measure which is higher or lower and how much Measured between points on a scale with even
units Example: Temperature in Fahrenheit or
Celsius
Example: Interval Measures
When distance between attributes has meaning, for example, temperature (in Fahrenheit)
Distance from 30-40 degrees = Distance from 70-80 degrees
Used for a variety of statistical analyses:
Central tendency can be measured by mode, median, or mean
Standard deviation can be calculated
Cannot calculate ratios
Index of Feminist Attitudes
Feminist Attitude index = 30 (highest score possible)
Feminist Attitude index = 5 (lowest score possible)
Do you agree or disagree with the following statements?
(SD =1, D=2, N=3, A=4, SA=5)
1. A woman should have the same job opportunities as a man.
2. Men should respect women more than they currently do.
3. America should pass the Equal Rights Amendment.
4. Women should be considered as seriously as men as candidates for the Presidency of the United States.
5. Doctors need to take women's health concerns more seriously.
6. Women have been treated unfairly on the basis of their gender throughout most of human history.
An index of their feminist attitudes was calculated from 6 questions, but the index had no absolute zero.
Ratio Level Measurement
Similar to interval level Can measure distance between two points But can do so in absolute terms
Ratio measures have a true zero (unlike interval measures) Example, can say that someone is twice as rich
as someone else based on the value of their assets.
To have no money is based on a starting point of zero
Ratio Level Measurement
Has an absolute zero that is meaningful
Can construct a meaningful ratio (fraction), for example, number of clients in past six months
It is meaningful to say that “...we had twice as many clients in this period as we did in the previous six months.
Ratio Level Measurement
Ratio scales are the ultimate when it comes to measurement scales
They tell us about the order
They tell us the exact value between units
AND also have an absolute zero Allows for a wide range of both
descriptive and inferential statistics
Types of Comparisons That Can Be Made With Different Levels of Measurement
Measurement Hierarchy
NOMINAL
ORDINAL
INTERVAL
RATIO
WEAKEST
STRONGEST