Glossary · Validity and evidence
Error families
The four kinds of error kept apart along the instrument chain: representation error, behavioral or trial variation, scoring error, and estimation error. Wrong world and wrong property are structural failures, not error families.
Also called: representation error, trial variation, scoring error, estimation error
Defined in
Handbook · FoundationsEvaluation is measurementA score is an observation, not a capability. Follow the instrument chain from construct to decision and the four places error gets in.Related terms
- Instrument chain
- The links through which a score supports a decision: target construct, sampled tasks and environments, trials and trajectories, grader readings, an estimate with uncertainty, and the decision. Error and invalid inference can enter at every link.
- Validation triad
- The system under test, the environment it acts in, and the specification its behavior is checked against. It exposes two structural failures: faithfully measuring the wrong world, and faithfully checking the wrong property.