Reference · Glossary
Confusion matrix
A table of **true vs predicted labels** — shows false positives and false negatives, not just overall accuracy.
When to use
When the cost of wrong “yes” differs from wrong “no” (spam, fraud, medical triage demos).
When not to
As the only metric when classes are wildly imbalanced — pair with precision/recall.
Example
| | Pred 0 | Pred 1 |
|--|--------|--------|
| True 0 | TN | FP |
| True 1 | FN | TP |