That's because there are strong value positions in different theoretical perspectives about how some things should be measured. Most criminal justice researchers at this point will at least decide what type of crime they're going to study. Operationalization is the process of taking a conceptual definition and making it more precise by linking it to one or more specific, concrete indicators or operational definitions. These are usually things with numbers in them that reflect empirical or observable reality. I don't want to give the impression from this example that researchers should rely upon statutory or legal definitions.
Some researchers do, but most often, operational definitions are also borrowed or created anew.
They're what link the world of ideas to the world of everyday reality. It's more important that ordinary people would agree on your indicators than other scientists or legislators, but again, avoid dictionary definitions. The most important thing to remember at this point, however, is your unit of analysis . You don't want to end up with a research project that has to collect political science data, sociological data, and psychological data. The nominal level of measurement describes variables that are categorical in nature.