A Primer on the Statistical Bridge

A Primer on the Statistical Bridge is an accessible introduction to the Statistical Bridge framework. It explains why correct mathematics and correct data processing are not enough to establish empirical validity, and introduces a small set of durable distinctions for reasoning about statistical work: bridge constitution, probability source, inference certificate, and claim license. Using a running customer-revenue example, the primer shows why event records and target populations can differ, why variation is not itself a probability source, why a probability source is not the same thing as an inference certificate, why a valid formal result does not automatically license a wider world-facing claim, and why representing an assumption inside a model does not increase its evidential warrant. It also introduces executable forward accounts as a way to strengthen internal reviewability without confusing simulation with truth about the world. The primer is intentionally non-comprehensive. Its purpose is orientation, intuition, and recall, while directing readers to the full framework in The Statistical Bridge, Version 3.0.