Hazard A + Vulnerability B ≠ Model C

If you want the executive summary, the title gives it away: combining hazard and vulnerability from two different sources doesn't necessarily create you a new model, much as it would be wonderfully efficient for us all to help create new views of risk. However, this article is intended to highlight the caveats around combining different views of hazard and vulnerability. This is with an eye on an exciting, impending era where Open Source catastrophe modelling is increasingly coming into focus as a viable second set of eyes on existing models. I want to use a very simple example of building a hurricane model using the same loss data and events, but subtle differences in the hazard. (Disclaime