Operationalizing Concepts

1
Operationalizing Concepts

• Issues in operationally defining your concepts,
  validity, reliability and scales

2
Review

• What is conceptualization?
• What is operationalization?
• Null Hypothesis construction Ho (p. 605)
• Logical, Value-neutral
• Asserts no difference between dependent and
  independent variables
• Alternative Hypothesis Ha (p. 145)
• Hypotheses and research questions

3
Operationalization

• Can anything be operationalized?
• Those who get to ask the questions get to
  determine the context of answers.
• Operationalization and social justice
• Avoiding bias (p. 152)
• Simple and complex operationalizations
• covering the construct

4
Operationalization in Action

• Try to operationalize these variables
• Teen mother
• Elderly
• Male homosexual
• Person with dementia
• Drug-abusing adolescent
• Criminal

5
Operationalization in Action, cont.

• Try to operationalize these variables
• Love
• Peace
• Anxiety
• Insomnia
• Attachment
• Cognitive-behavioral therapy

6
Levels of Measurement (p. 172)

• Nominal
• Ordinal
• Interval
• Ratio

7
Measurement Error

• Random Error
• Systematic Error

8
How We Collect Data

• Direct self-report
• Indirect self-report
• Observation
• Archival records

9
Two Principles in Reducing Measurement Error

• Reliability
• Definition gives the same answer over time and
  among different populations and circumstances
• Types of reliability
• Interrater reliability
• Test-retest reliability
• Internal consistency reliability
• Inter-item correlations (p. 187)

10
Two Principles in Reducing Measurement Error

• Validity (p. 194)
• Definition Measures what it means to measure
• Face validity
• Content validity
• Criterion-related validity
• Concurrent validity
• Predictive validity
• Construct validity

11
Validity and Reliability, final words

• P. 198, for permutations
• Valid, but not reliable
• Reliable, but not valid
• Valid and Reliable

12
Constructing Measurement Instruments

• Why construct measurement instruments?
• Covering the construct
• Complex constructs, subtle constructs
• Convergent and discriminant validity
• No-nos when constructing measurement instruments
  (pp. 208 212)
• Tools
• Likert scaling
• Semantic differential scaling (p. 226)

13
Single-Systems Design Experiment

• Consider a behavior you want to extinguish or
  increase
• Consider a reward and/or punishment