Glossary · Reliability, calibration, and statistics
Discordant pairs
In a paired comparison of two systems on the same tasks, the tasks on which exactly one system passes. Only discordant pairs carry information about which system is better; McNemar's test uses only them.
Defined in
Handbook · ValidationComparing systemsPair tasks, count discordant pairs, size for the smallest difference that matters, and never let significance stand in for validity.Related terms
- McNemar's test
- A paired test for binary outcomes: χ² = (b − c)²/(b + c), where b and c count the tasks that only one of the two systems passes. Use the exact binomial version when b + c is small.
Where it comes up
- Notation and formula cardHandbook · Reference
- Comparing two systems on the same tasksCalculator