A lot has happened in the last year regarding The Decision Model. In November 2009, our book described the formalism and usage of The Decision Model (von Halle and Goldberg, 2009, Taylor & Francis LLC, The Decision Model: A Business Logic Framework Linking business and Technology). Since then, adoption of The Decision Model has escalated faster than anticipated. It also caught the attention of the Object Management Group which is the subject of this month’s column.
This column provides information to Modern Analyst readers regarding the OMG and its interest in decision models.
The OMG
The OMG is a standards group. Standards groups do not invent models, notations, or languages. Instead, they identify commonality among existing ones where these are often “incompatible” for various trivial reasons, or can be made common with some simple extensions.
In particular, the mission of the OMG is “to develop, with our worldwide membership, enterprise integration standards that provide real-world value. OMG is also dedicated to promoting business technology and optimization for innovation through its Business Ecology® Initiative (BEI) program and associated Communities of Practice.”
The standards set forth by the OMG, when implemented by software vendors, benefit the end customer.
The Decision Model’s Debut at the OMG
In late 2009, prior to the publication of our book, Larry Goldberg gave a presentation to members of the OMG who are working on business rule standards. His presentation introduced The Decision Model as a rigorous normalized model for business logic that our clients had been using in practice for several years.
The Nascent OMG Standard: Decision Model and Notation
Some members, recognizing the value of decision modeling in bridging and supporting the other rule standards in OMG, proposed a Decision Model Notation with the acronym DMN.
The DMN’s goals are the following:
- Provide a standard framework for decision model types
- Provide a standard notation for decision models, decision tables and potentially other metaphors, together with technology-agnostic standardized semantics
- Provide common notations for decisions in business process models (i.e., BPMN)
- Provide for interchangeability for decision models and tables among modeling tools.
The DMN Decision Model is not the same as The Decision Model
In this column, we need to differentiate between what the DMN means by decision model and what we mean. To clarify these distinctions, the phrase “decision model” can refer to various ways of representing logic, which are all potential targets of the DMN’s work. The phrase “The Decision Model” or “Decision Model” refers specifically to the one formal model for business logic in our book and that model’s fifteen principles. Clearly DMN will attempt to provide a common framework that covers general decision models, INCLUDING The Decision Model!
DMN Activities in 2010
During 2010, the DMN committee met several times to investigate existing metaphors for representing the logic of decisions, existing standards, relevant methodologies, the use of decision tables by BPMS (i.e., business process management systems) and BRMS (i.e., business rule management systems). They also explored the potential relationship between decision logic and SBVR (i.e., OMG standard for semantics of business vocabulary and rules).
Jan Vanthienen from Katholieke Universiteit Leuven in Belgium, an expert in decision tables, also presented to OMG on the value of decision tables as a way to represent general decision models and business rules. Decision Tables represent a common metaphor in many BPMS and BRMS systems, often allowing the validation of completeness (i.e., covering every possible input combination) and exclusivity (i.e., producing only one outcome for each possible input). He also shared results of a survey which concluded that people prefer such tabular representations to tree representations (such as decision trees), and both these to textual rule expressions.
The DMN domain also covers topics such as rule languages, decision management, decision tables, decision trees, decision graphs, rule flows, and score models.
The Decision Model and the DMN
Last month, in Cambridge Massachusetts, we (Larry and Barb) attended the OMG Technical Meeting to give an update on The Decision Model. The presentation titled “The Decision Model: A Refresher and what’s New since Last Time” covered the following:
- The Problem of Business Rules (Logic)
- Introduction To The Decision Model
- Top Down, Iterative, Agile
- Recent Advances in the Model and Practice
- Decisions versus Process
- Real-World Experiences and Reactions
A Refresher on The Decision Model
Most of the topics were a review of the earlier OMG presentation and have been covered previously in the BDM bulletins.
Recent Advances in the Decision Model and Practice
The topics in the September 2010 presentation also addressed “what is new since last time” such as recent advances and real-world experiences with large users of The Decision Model. Perhaps the most notable advance was the introduction of Decision Model Views. We covered Decision Model views in the BDM in the past.
Because a Decision Model is a holistic, connected model, the idea of creating various “views” or filters on a basic Decision Model works well to customize Decision Models for the different logic needed for various geographical, political, glossary, or customer-based requirements. Use of Decision Model Views provides a rapid and holistic way to create business-specific customizations of business logic.
The Decision Model has also proved useful in documenting and automating data quality logic (versus pure business logic) and doing the same for data translation logic.
Real-world Experiences with The Decision Model
Real-world experiences included three important achievements: generation of test cases, straight-through automation, and modeling tools.
Regarding test cases, it turns out that The Decision Model offers a significant breakthrough in identifying test cases, reducing total cost and time of testing efforts. In a recent webinar called “The Decision Model: Revolutionizing Testing Process and Accuracy,” Larry revealed a methodology for generating and reducing test cases directly from a Decision Model. He pointed out that The Decision Model “enables the business logic and testing to be closely aligned, dramatically reducing coding time, testing effort, and error rates in the code itself.”
Regarding, straight-through automation, this means Decision Models have been imported into a BRMS without programmer intervention, significantly reducing the time from business policy changes to automation.
As far as modeling tools go, a Decision Modeling capability is now available in a requirements tool (InteGREAT from www.edevtech.com) and more tools are on the horizon.
Favorable Reactions
New testimonials regarding use of the Decision Model have come from many places in 2010. Some included in the September 2010 presentation were:
- “We have been testing the decision model approach, our process maps have significantly reduced in size, and the reuse has dramatically increased so the approach works.”
- “This approach will allow me to actually separate business decisions from processes and create rules based glossaries. “
- “I read this book and then developed a decision model for a process model from a past project. It worked well and provided insight to business logic not noted (missing) in the process model. Using the decision model provided value added to my analysis. I will definitely augment my process models with decision models in the future. “
DMN Reaction to the September 2010 Presentation
While the original presentation in 2009 was interesting to its audience, the presentation in September 2010 seemed even more so. Paul Vincent described it on the TIBCO CEP blog as “a thought-provoking presentation by Barbara von Halle and Larry Goldberg of KPI on their KPI Decision Model which is proving very attractive to business analysts.”
The September 2010 presentation made it clear to OMG that The Decision Model is more than a simple decision table and utilizes a rigorous collection of two-dimensional tables (albeit similar to decision tables). Based on business logic, the tables of The Decision model are organized according to the natural connections among these tables and are normalized according to logical principles.
This revelation led to an interesting and vigorous discussion after the presentation.
The DMN’s Discussion about the Decision Model
Based on the DMN mission and renewed understanding of The Decision Model, the DMN team raised four questions, listed below, and followed by our answers.
1. How does the Decision Model relate to SBVR? (As a reminder, there are two parts to SBVR – the part for expressing business rules and the part for formulating terms and facts referenced in business rules).
Most often, our clients do not use SBVR for expressing the types of “business rules” that SBVR defines. This is because The Decision Model structure, content, and integrity principles are sufficient for communicating the needs of the business logic between business and IT. In fact, IT organizations within our clients accept Decision Models as a standard requirement for input to IT for development.
However, when the business logic in a Decision Model relates to legal requirements or contractual issues, clients sometimes translate Rule Family rows into SBVR statements to create formal documentation.
Some clients use the vocabulary part of SBVR for defining the terms and facts used to create the condition and conclusion fact types in The Decision Model. Some do so even if they are not using SBVR expressions for expressing the logic.
2. How does The Decision Model relate to the BMM (i.e., the OMG standard called Business Motivation Model http://www.omg.org/technology/documents/br_pm_spec_catalog.htm)?
The BMM is extremely important to The Decision Model. We always encourage clients to associate an entire Decision Model to the goals associated with the BMM. In particular this includes the measurable business objectives we expect The Decision Model to enable. This also includes specific business performance metrics with which to measure the related Decision Model’s effectiveness. The latter assists in determining if, and perhaps how, the Decision Model’s logic needs to be changed.
In addition, the BMM is an important ingredient in The Decision Model Certification program. The certification program consists of attending formal training, completing several months experience, scoring well on a written exam, and passing an oral dissertation. The oral dissertation involves defending a real-world Decision Model, not only its content but also its justification based on business motivations, objectives, and measurable impact on the business.
This role of the BMM on Decision Model projects keeps the project within scope, always aiming for actual business impact.
3. How does The Decision Model relate to other OMG models?
We encourage clients to use BPMN for business process models, with one important modification. Instead of using the “business rule” task we introduce the notion of a “decision task”. A decision task is simply a process task, guided by an entire Decision Model (not a list of business rules).
We do not require UML models, but most often, clients create UML data or object models of the persistent data behind Decision Model conditions and conclusions. These models are transparent to the business people but are cross-referenced to the fact types in the Decision Models.
4. Is there a metamodel that supports The Decision Model?
The metamodel supporting The Decision Model has evolved over the past few years. Its current version supports client software behind The Decision Model life cycle, from Decision Model creation, business validation, and importing it into a BRMS.
The Pursuit of a Decision Model Notation Standard
The morning after the presentation, the DMN team continued discussions relating The Decision Model to a possible standard and have since continued work on an RFP that will seeking formal proposals for this decision model notation standard.
The ultimate intent is for the DMN standard to include all the various types of representations for decision logic, including trees, tables, as well as models of the type of The Decision Model. It is therefore our hope that the standard provide will a framework into which The Decision Model fits, and enable a wider audience of users and modeling tools to have access to The Decision Model. In addition, the standard would provide guidance to how such representations connect to and evolve with other OMG standards such as the ever-popular BPMN.
We believe Modern Analyst readers, Decision Model practitioners, and software vendors will all benefit from a DMN standard that meets these goals. A standard in this area will further encourage organizations to build better decision logic alongside all the other enterprise architectural pieces that are often based on OMG standards.
Next Steps
The DMN will be an “open” (OMG) standards process and information on it will be published by OMG and others. DMN is still at the pre-RFP stage so it has a way to go to become a standard yet.
The RFP will seek a standard for “decision models, in particular those used commonly in BPM. It standardizes the subset of Business Rule Management System (BRMS) usage to do with decision modeling and management. It should also be compatible with executing decisions in other software models and systems, such as within UML Activity Diagrams, Complex Event Processing, etc.
It is not intended that DMN support exclusively software-based automated systems, but that other systems such as Decision Support Systems supporting human decisions may re-use its notations and metamodel. However, the primary audience is expected to be the community with most to gain from standardization – that of the IT and decision modeling communities” [from the DMN RFP wiki].
Readers interested in promoting such a standard can consider the following:
- Follow Paul Vincent’s blog (http://tibcoblogs.com/cep/tag/dmn/ )
- Become familiar with the RFP and give feedback.
- Provide some requirements document for the standard developers (a major US bank has already done this).
- Participate, or encourage others to participate, or submit a proposal.
The Time is Now
A lot has happened in the last one to two years regarding The Decision Model: the book, adoption by major corporations, advancement of the model and its practice, software announcements and a new DMN standards committee.
We believe that these successes with The Decision Model prove that the time is now. Today, every organization needs a model for specifying and automating business decisions and logic.
We also believe The Decision Model brings a higher level of maturity to the management of business rules and logic than other representations have in the past. Specifically, we find that people prefer The Decision Model to tables, tables over trees, and trees to textual expressions. More importantly, a true model attracts higher management attention than do other representations. That is because, business logic, cast in Decision Models, emerges as a new business asset. It may turn out to be the most important business asset yet.
We leave the last word to one of the DMN RFP authors. Paul Vincent stated in his blog, “Decision modeling could become the dominant analysis aspect in future years: consider a business process like “loan approval” and you don’t need a degree in computer science to work out that the business process is there just to support the business decision on whether to approve a loan! So in summary: DMN is looking like it could be very useful.”
