Corruption is one of the most discussed concepts in the world. Usages escalate from bribery through untoward business-government connections on up to culture and human nature. Measures at the national level include amalgamations of perceptions and of “experience.” Since corruption conveys shame and blame, concepts and measures are especially controversial.
This paper shows how definitions can be induced from examples and framed in terms of political economy models. It examines the coherence, reliability, and predictive power of measures of corruption.
Although this paper deals with corruption, it may serve as a methodological warm-up exercise for other important topics in the social sciences, from democracy to mental health, from sustainability to poverty, where we need to clarify what we are talking about.