Measuring social constructions? On the meaningful difference between indexing and measurement

Many psychological constructs of interest are fuzzy, and are ultimately social constructions. However, how social constructions relate to measurement models - how they should be meas-ured, and if they’re measurable in the first place - is a big open question in the philosophy of psychometrics. In this article, we propose a meaningful distinction between measurement and indexing by discussing the role of causality versus constitutive relations. We also discuss how social constructions can be handled, and tackle other issues in ontology and causality.