The document discusses various concepts and strategies related to measurement in the social sciences, including defining different levels of measurement such as nominal, ordinal, interval and ratio scales. It also covers developing operational definitions and valid and reliable measures for concepts through careful consideration of indicators and data collection methods. Strategies for assessing validity and reliability of measures like test-retest analysis are presented.
4. Measurement
Systematic observation and representation using
scores or numerals of variables under investigation
Numeral: Symbol in form 1, 2, 3, or I, II, III, etc.
Numeral with quantitative meaning = Number
Numbers: Description, Explanation, Prediction
5. Numbers assigned to objects or events
Example: DummyVariable for Gender
▪ 1 = Females, 0 = “Otherwise” (Males)
A rule specifies a process used to assign numerals
or numbers to objects and events
Example: Freedom House
6. POLITICAL RIGHTS
Electoral Process
Political Participation
Functioning of
Government
CIVIL LIBERTIES
Freedom of Expression
Associational /
Organizational Rights
Rule of Law
Personal Autonomy and
Individual Rights
Free = 1.0 to 2.5
Partly Free = 3.0 to 5.5 Not Free = 5.5 to 7.0
7. FREE PARTLY FREE NOT FREE
Americas 24 (69%) 10 (28%) 1 (3%)
Asia-Pacific 16 (41%) 15 (38%) 8 (21%)
Central /
East Europe
13 (45%) 9 (31%) 7 (24%)
Middle East /
North Africa
1 (6%) 4 (22%) 13 (72%)
Sub-Saharan
Africa
9 (18%) 21 (43%) 19 (39%)
Western Europe 24 (96%) 1 (4%) 0 (0%)
8. Restating concept so it can be tested
How will we measure concept?
Operational Definition: Deciding what kinds
of observations should be made to measure
occurrence of attribute or behavior
9. Step #1: Thinking through what concept
means and how will we define it
Step #2: Decide which variables we will use
to measure concept
Step #3: Propose specific indicators of concept
Step #4: Select data sets or instruments to
measure indicators
16. Variable X has values X1, X2, and X3
X1 < X2 < X3
Uncertainty of Equality Between Values
Example: Olympic Performance
X1 = Bronze Medal
X2 = Silver Medal
X3 = Gold Medal
17. Variable X has values X1, X2, and X3
X1 > X2 > X3
Equality
NoTrue Zero
Example:
Temperature
18. Interval variable with true zero point
Examples: Income,Years of Education
19.
20. Dichotomous
Variable that can take on only two values
Example: Gender (Either Male or Female)
Discrete
Orderable variable that can take on limited values
Examples: 1, 2, 3, 4; 1979, 1980, 1981, 1982
Continuous
Orderable variable that can take on limitless set of values
Example: Decimals Pi = 3.14159…
21.
22.
23. Extent to which a measurement procedure
measures what it intends to measure
Valid measure provides true and accurate
picture of something
24. Does the measure appear to be valid “on face?”
To properly assess face validity, need to know:
▪ Meaning of the concept being measured
▪ Whether information collected is germane to concept
Examples: Political Ideology; IQTests
25. Extent to which measuring instrument
consistently measures what it is measuring
Consistent results across individuals / times
26. Type of Reliability How to Measure
Stability orTest-Retest
Give the same assessment twice,
separated by days, weeks, or
months. Reliability is stated as the
correlation between scores atTime
1 andTime 2.
Alternate Form
Create two forms of the same test
(vary the items slightly). Reliability
is stated as correlation between
scores ofTest 1 andTest 2.
Internal Consistency
Compare one half of the test to the
other half.
27. Two researchers independently find same
results when looking at data
Why would this be useful?