BPDMF2 — BPDM RTF Issue: Explicit modeling of decisions vs BPDM

At the BMI meeting on 10Dec07/Burlingame, there was a discussion on decision modeling and its relationship to existing modeling needs and standards. An action from the meeting was to raise the question of whether decision modeling was explicitly, or could explicitly, be “handled” within BPDM (and consequently, whether BPDM should model decisions more explicitly).

Comments:

From my understanding of BPDM, a decision activity can simply be a BPDM activity, and modelled via Behavioral Step / Change Condition Step, which is probably too low level to be useful for talking about decisions in processes, but may be necessary for mapping decisions into processes.

This is going to be difficult to answer without a formal definition of a decision model. And I am not going to define one at this stage of discussions! J However, it is probably safe to assume that a Decision Table is an instance of a Decision Model. And that invoking decision tables (and services) in BPM activities is pretty common. So hopefully the concept is not too alien to the BPM community. Disclaimer: of course issue may be revised as the terminology is refined.

Personally, I think the answer is “yes” in that decision processes in BPDM (1/2) can accommodate decision services and processes (eg as custom external activities prior to a BPMN gateway), but BPDM (1/2) does not include business-level decision modeling, and that decisions and process are probably orthogonal, and that BPDM should simply reference any future decision model as a special activity as required.

Related to this is some of the BPDM positioning I have seen which implies a (SBVR-type) business rule is also embedded in processes. It is far more likely that SBVR type business rules dictate and direct the development of processes, and impact their behaviour, rather than are directly included in processes. At best there is traceability from process definition to SBVR business rule and BMM constructs. Much more likely is the idea that processes embed decisions and “operational business rules” (rules with behaviour, IMHO) (which typically are represented as production rules in automated processes).