Decision Modeling (DMN)

The value and adoption of decision modeling has accelerated since the Decision Model & Notation (DMN) open standard was published by the OMG in 2015.

DMN Model

DMN decision models and decision tables like these allow business decision-making to be formalized and automated.

automated booking decision table
booking fraud decision table

The open standard enables the following:

Business Advantages

Using decision modeling, you can:

  • Express business logic in a manner that is both meaningful to the business and executable.
    • It means that there is a single ‘prime record’ for business requirements that is both comprehensible to the business and deployable to a run-time system.
    • This eliminates the errors that occur when translating specifications to implementation code.
    • It puts the business subject matter expert and business analyst in the driving seat creating a more effective collaboration between business experts and IT personnel.
    • Test driven development of decisions. The executable nature of decision models allows them to simulate business logic against test data, giving business users an opportunity to ‘kick the tyres’ of their decisions.
  • Quickly identify which data is really needed.
    • Sketching a decision model is the quickest way to determine what data you really need and the required data quality (i.e., latency, accuracy, completeness) to support decision-making.
    • As decision management is incremental it works well with Agile methodologies.
    • Decision modeling therefore makes data provisioning more accurate: avoiding the cost of over-provisioning and the delays of late discovery of missing vital data items.
  • Perform impact analysis.
    • Because decision modeling focuses on the dependencies between decisions, sub-decisions, authorities and data, it allows a rapid assessment of the business and technical impact of changes to these things.
    • Helps businesses to assess the true cost of internal change and the impact of externally imposed change.
  • Make implicit business knowledge explicit.
    • Decision modeling helps to reveal and address any flaws or inconsistencies in the accepted wisdom of decision-making.
  • Commoditize business knowledge.
    • Decision modeling offers a vehicle for companies to buy and sell business expertise (e.g., regulatory standards, legal constraints, industry conventions).
  • Standardization and Integration with business process modeling (BPMN). All Business Analysts and tools will use the same format to represent decision modeling.

Sweet Spot

Decision modeling can be beneficial in many areas, particularly areas needing to handle:

  • High value
  • High transparency
  • Scalability

Image reproduced with permission
Real-World Decision Modeling with DMN, James Taylor and Jan Purchase, 2016

OMG Example

The OMG provide this example to show how decision modeling can be used in conjunction with BPM and decision tables. Here you can see how a decision model to accept/decline an application is used within a business process – and a decision table used to specify the logic for eligibility with the decision model.

Further Reading