Anomaly detection inverts aito.._predict: instead of asking “what's the most likely value?” we ask “how likely is the value that's actually there?”. For a PO from Wärtsilä Components, Aito predicts the account code from the supplier alone; an account it gives little probability to scores high, as (1 − p) × 100. Amount spikes and first-time vendors use the same score, with p counted from a _search over the purchase history. No rules, no thresholds to maintain.