Weighting in additive scores can quietly make dimensions necessary.

Evidence

A necessary dimension is more heavily weighted than nonnecessary dimensions. An additive, family resemblance measure can have de facto necessary dimensions if a dimension’s sufficiency weight is high enough. For example, take a three-dimensional concept with a family resemblance structure and secondary-level weights of 5, 3, and 2. If the rule is that a sum of 6 or more is required to be in the family then dimension 1 is necessary because 2+3 does not get over the bar. — Gary Goertz, Social Science Concepts, 679

Categorization

• SEED: Angle: ‘Your index isn’t additive — the weights you chose just made some variables secretly necessary,’ a piece on how scoring rules smuggle in conceptual assumptions.