> For the complete documentation index, see [llms.txt](https://metya.gitbook.io/metya/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://metya.gitbook.io/metya/glossary-and-references/metrics-and-method.md).

# Metrics & Method

* Effective transaction — A transaction that authorizes successfully and posts within the clearing window; voids and full refunds are excluded.
* Active merchant — A merchant with ≥ 1 redemption/settlement in a calendar month.
* Rebate utilization — The share (by amount/count) of issued rebates that were successfully used within the period.
* Anomaly rate — Share of events that trigger risk controls (rejection/rate-limit/review); computed independently from technical failure rates.
* Sybil detection — Combined signals from device fingerprint, IP/ASN, session similarity, geo consistency, MCC profiling, and counterparty graph. Low-quality ME is excluded from denominators.