Tutorial: Creating a vulnerability mapping

The vulnerability mapping represents the relationship between hazards and impacts and, if applicable, risk reduction measures. It is typically based on the vulnerability relationships in the CVI library developed in task 2.2, but any other source, e.g. from literature or expert opinion, can be used as well. 

The mapping defines the state of the impact variable conditional on a combination of states of its parents. Such a mapping for an impact variable can be best made in a spreadsheet following the steps 1-4. 

1. Create a row for each parent node in the same order in which they have been specified as "parents" in the Cnodes.json 
2. Write out all combinations of parent states. The states must change in the order in which they have been specified in their respective "bins" fields. Moreover, the states of the last parent must change fastest, then the ones of the second last, and so on until the first parent, whose states must change slowest.
3. Indicate for each combination of parent nodes in which state the impact variable of interest should be in terms of its state index
4. Copy the state indexes as a 1D array into the field "mapping" of that impact variable in the vulnerabilties.json files

Below are two examples with from the demoBN. Refer to the Cnodes.json file to verify the order of parent nodes, and to the Hnodes.json file, Rnodes.json file and Mnodes.json file for the order of states. 

Example 1: Relative damage to residential buildings

This vulnerability mapping is based on the flood damage curve for Belgium in the CVI library. Additionally the assumption has been made that sandbags can withstand a flood depth of 50cm, which means that depths less than 50cm do not lead to damage, because the building itself is kept dry, while depth higher than 50cm lead to the same damage as before, because the bags overflow. 

Example 2: Risk to Life