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Proposition pair

Definition

The two competing hypotheses that frame an evaluative opinion: typically a prosecution proposition (Hp) and a defence proposition (Hd). A compliant report must state both propositions explicitly before expressing the likelihood ratio.

Related terms

Accreditation body
A national or regional organisation that assesses laboratories against ISO/IEC 17025 and grants accreditation. Examples include UKAS (United Kingdom Accreditation Service), NIST-associated...
ENFSI Guideline for Evaluative Reporting
A consensus guidance document from the European Network of Forensic Science Institutes that defines how member laboratories should express evaluative opinions. It...
ILAC G19
A guidance document from the International Laboratory Accreditation Cooperation on the use of uncertainty of measurement in forensic science reporting. It requires...
ISO 17025
International standard for the general requirements for the competence of testing and calibration laboratories. Covers management system requirements (document control, internal audits,...
Verbal scale
The ENFSI translation of numerical likelihood ratios into courtroom language: very strong support (LR over 10,000), strong support (LR 1,000-10,000), moderate support...

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