Concepts can be evaluated by how accurately they describe real-world phenomena.

Evidence

Hence one conceptual ball is descriptive validity or what might be called empirical validity. A core goal of all sciences—natural and social—is to accurately describe the world. This means that this book rejects a nominalist view of concepts and, in contrast, takes a realist view of them. Good concepts accurately describe the world. — Gary Goertz, Social Science Concepts and Measurement, 58

Categorization

• DEFINE: Defines descriptive/empirical validity and stakes a realist versus nominalist position on concepts.