Comments on: Deeper Into Simulation - Part 1

By: BPMS Watch » Announcing the BPMN Training

BPMS Watch » Announcing the BPMN Training — Tue, 06 Feb 2007 21:58:52 +0000

[...] The third section, Simulation Analysis with BPMN, shows how to do practical performance analysis using BPMN in combination with the modeling tool’s simulation engine. Simulation isn’t standardized by BPMN, so this part is somewhat tool-dependent, although the principles behind it are not. We walk through three specific use cases, which I have discussed previously: cycle time improvement from eliminating handoff delays and other inefficiencies, optimizing resource configuration and utilization, and activity-based costing. We show you how to use various diagram patterns, how to set up the simulation parameters, and how to customize the simulation output to give meaningful results. [...]

By: BPMS Watch » Deeper Into Simulation - Part 2: Optimizing Resource Utilization

Fri, 05 Jan 2007 23:38:02 +0000

[...] Continuing my recent post re simulation analysis and BPMN… (Since then I’ve finished my BPMN training materials, including simulation analysis, and it’s now in beta… almost ready to go! Also since that post, the histogram of costs and times is now out of the box. I told ITP Commerce how I did it and they put that in the standard simulation output. How’s that for customer service!) [...]

By: DGray

DGray — Wed, 03 Jan 2007 14:26:06 +0000

Bruce,

Let’s deal with Use Case 1 only. The first question to answer is why does anyone want to know process cycel-time? Okay, that’s an easy question. If I am the process ‘owner’ I want to know that my process is both ‘effective’ (the process works - generates correct output) and is ‘efficient’ (the lowest cost vs time to produce quality output).

A process owner will estalbish Key Performace Indicators (KPIs) within their process to help determine effectivness and efficiency. Cycle-time can help them with selecting correct KPIs. I also want to determine the best possible cycle-time irrespective of resources available (I do this by setting resources to unlimited). In other words, if there is a task to be done we have a resource available to do it providing the work is ‘in scheduled’ time.

However, when capturing task metrics one might follow the Goals/Questions/Metrics (GQM) methodology for efficiency by asking:
1. What triggers the task?
2. How often is the task executed?
3. What is the duration of the task?

Let’s focus on question 3 in determining cycle-time. Most process analysts ask the question and ask for two parameters: Minimum time - How fast can you do this task (presuming your boss tells you to drop everything else and get ‘it’ done; and Maximum time - How long have your ever taken do get this task completed.

With those two metrics alone, and setting the simulation engine to select either a ‘normal’ or ‘constant’ distirbution between the Minimum/Maximum times, we would end up loosing a lot of ‘work’ done that would not be accounted for in the resulting inacurate cycle-time calculation. For those following a sig-sigma approach a third metric may be more desirable to include: Typical time - How long it ‘normally’ takes the resource to complete the task. The The deviation from the mean can now be more accurately measured deriving a more accurate cycle-time.

Note: Be sceptical about task metrics provided where typical time = ether minimum or maximum time as the resulting distirbution will resemble a right/left triangle and inacurate cycle-time calculation.

- David M. Gray

By: rlogg

rlogg — Sun, 31 Dec 2006 17:56:05 +0000

Bruce,
an excellent start for simulation activities with value for the business. In my blog I also reflected a bit on simulation and the limitations (mainly from a reality modeling perspective) of current BPM tools.
http://process-transformation.blogspot.com/2006/12/bpm-and-simulation-are-we-there.html

Regards,
Roeland Loggen