From features to tariff: a short, defensible path. Match distribution/link to the task (Poisson for frequency, Gamma/Tweedie for severity/premium; often a log link). Set exposure/offset and keep loadings outside the model. For features, prefer sensible grouping (categoricals), binning/transformations (numerics), and only explainable interactions. Validate with hold-out/rolling, add regularisation, and track coefficient stability. When communicating, translate […]

The math is simple — interpretation drives decisions. Start with link ratio stability across the triangle. Jumps, “special years,” or process changes suggest a shorter lookback or portfolio splits. Decide if a tail factor is warranted and how much weight it carries versus data. Check paid vs incurred coherence; persistent gaps can be more telling

Turn “what if…?” into a variant you can ship. Start with a crisp hypothesis: e.g., “+8% base tariff in SME improves net result without breaching target LR.” Lock your success metrics (premium, LR, net pre/post reserves) and guardrails (e.g., max +10% price). Change one lever at a time: tariff, acquisition, frequency, severity, reserves. Create 2–3