An Example Decision Model

This example Decision Model uses the basic and common elements of the Decision Model and Notation language to demonstrate and exemplify a business decision that we all have probably been interested in at some point - the HR Review decision resulting in a possible wage raise or promotion.

The HR Review Decision element does not itself define rules but rather is of type Invocation, which calls the services of the Promotion Rules element. This is a Business Knowledge Model (BKM) that can be reused in different contexts. The BKM defines the rules for promotion in a Decision Table that is stored internally, and when it is called it passes the resulting output back to the Decision element.

The Decision element has two inputs, namely Key Performance Indicator (KPI) Data and Project Data - this data is used as input to the decision. Enterprise Architect has a helpful mechanism for defining different data sets that can be used to simulate the Decisions and effectively allow business and technical users to perform 'what-if' analysis as part of pre-production testing or in-production support analysis. The Decision Expression editor helps you to create and modify rules in an easy to use table that colors the input and output columns and has a number of built-in features that make it easy for business and technology users to work with decisions. Any number of Annotation columns can be inserted to create additional documentation to explain the expressions.

Enterprise Architect is a full life-cycle tool, and once the Decision Models have been created and tested they can be generated to implementation code, ensuring that the decisions that the business defines are enshrined in code. As part of the testing process the tool provides a simulation engine that allows the models to be visualized as though they were in a production system. Any number of data sets can be defined and used with the simulation to test the decision logic and thus avoid errors occurring in production systems.