URS 6806: Measurement

[Chapters covered in this section: 4]

Conceptualizing Variables

• Concept: A notion or a social observation [e.g. politeness, crime, intelligence, unemployment]
• Dimension: A specific aspect of a concept [e.g. politeness could include several dimensions: a reciprocal smile; opening the door for another person; waving in recognition; indulging in small talk]
• Indicator: A sign of presence or absence of a concept.
• Operational definition of a Variable: A specific measurable concept [along one or more dimensions]

Types of variables:

• Independent
• Dependent
• Constants
• Control variables

Link between variables

• Covariation of variables: Direct, Inverse, Non-linear
• Relationships between variables: Causal; Directional
  • Criteria for causality:
    • Correlation (cause and effect have some actual relationship)
    • Time Order (cause precedes effect)
    • Nonspurious (effect cannot be explained by a third plausible variable)
    • Necessary and sufficient causes

Units of Analysis

• Individuals
• Social groups
• Organizations
• Social artifacts
• Issues with Unit of Analysis
  • Ecological fallacy
  • Reductionism

Measurement of Variables

• Nominal: Variables with characteristics of exhaustiveness and mutual exclusiveness; labels or characteristics
• Ordinal: Variables with attributes that can have a logical rank order
• Interval: Variables with logical distances between attributes; not based on a true zero point (e.g. Celsius degrees)
• Ratio: Variables with logical distances between attributes, but are based on a true zero point
• Issues with measurement
  • Reliability (stability; equivalence; internal consistency)
  • Operational validity (face; content; criterion--concurrent/ predictive)
  • Sensitivity