When it comes to building products, one of the more complex tasks can be defining the rules and calculations required to make decisions regarding eligibility and entitlement. The Cúram Express Rules language has been designed with this specific task in mind. It works on the premise that every rule is based on a question and an answer to that question. Related questions can be grouped together, and a hierarchy of question-dependencies can be established.
In determining eligibility and entitlement for a product, there can be any number of questions asked of potential product recipients in order to establish their needs. A good rules designer will create effective rules - rather than creating a flat list of many questions, the rules designer will create a smaller number of questions, with the answers feeding into other calculations.
Products can have three different types of rules:
Rules design for decision display and key decision factor rules is approached differently to eligibility and entitlement rules. For decision display rules, the design process begins with figuring out what decision information is necessary and important to be displayed. This can be done through screen designs. Once the visual requirements are defined, it is then a matter of figuring out how to extract the necessary information to populate the screens. This information can come from the eligibility and entitlement rules results, but it can also come from unique decision display rules that have nothing to do with eligibility and entitlement decisions. For example, reasons for a sanction recommendation may be derived purely from the evidence captured for a client.
For key decision factor rules, the design process requires thinking about key pieces of data that would be useful to display in a determination result. For example, it may be useful to display the increase or decrease in the number of household members on a case, or the changes in combined household income over time.