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CRIM 430. Lecture 3: Concepts, Operationalization, and Measurement. Concepts to Measurement. Conceptualization: Process by which we specify precisely what we mean when we use certain terms—working agreements to keep everyone on the “same page”
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CRIM 430 Lecture 3: Concepts, Operationalization, and Measurement
Concepts to Measurement • Conceptualization: Process by which we specify precisely what we mean when we use certain terms—working agreements to keep everyone on the “same page” • Indicators: specification for determining the presence or absence of a concept • E.g., crime seriousness (concept)harm to victim (indicator) • Dimensions: Groupings within an indicator • E.g., harm to victim (indicator)physical harm, economic harm (dimensions) • Conceptual definition: Result of conceptualization—a working definition specifically assigned to a term • Operational definition: Definition that clarifies exactly how the concept will be measured—most be specific and unambiguous • Use the operational definition to conduct measurements in the real world • These are decisions that you must make based on the literature and your expertise • Not everyone will agree on how you define each level—you must be able to justify your terms
Measurement • Process of assigning numbers or labels to units of analysis in order to represent conceptual properties • Requires making observations and scoring those observations • Measurement depends on the decisions made at the conceptual and operational definition levels
Measures • Measures=Variables • Measures should be exhaustive: Represent all possible characteristics • Measures should be exclusive: Must be able to classify each observation in terms of one and only one attribute
Levels of Measurement • Nominal: Variable has only characteristics of exhaustiveness and exclusiveness- • No rank ordering • Ordinal: Variables whose attributes may be logically rank ordered but the difference between each attribute is not relevant or measured • Interval: Variables in which the distance between rank ordered attributes is meaningful • Ratio: Same as interval but are based on a true zero point
Criteria for Measurement Quality • Reliability=Consistency…Does a measurement technique yield the same result each time when repeatedly applied? • Validity=Accuracy…Does an empirical measure adequately reflect the meaning of the concept under consideration? • Good measurement has both reliability and validity