Causal loops ->> stock and flow (modelling)

[Ralf]

Hello,

I just realized that there is a way to attach models on the postings. As I have had just a discussion with a friend down in New Zealand on the effects of lean (=improvement) activities we both wondered how to change the CLD into a simulation model with stocks and flows.

The short story on the model is:

1. Gap between assumed outcome and actual outcome
2. Doing lean workshop (2 days)
3. Through the 2 days absence there is three days of backlog work (as the person is a specialist)
4. Effects in the short run (eroding quality and performance)
5. Effects in the long run (usage of the learned methods)

By the way there are two views (Flo is a modified one based on my own view Ralf).

The only we both could think of is the "unfinished workload".

Is that really it or are there other stocks in the diagram we didn't uncover?

Thanks a lot for your support.

Best regards

Ralf

[bob@vensim.com]

The obvious levels from the diagram are: Lean Activities, Satisfaction of Workers, Underlying Quality of Work (driven by Improvement) and Motivation. Thais said, these diagrams are not something that can easily be turned into useful simulation models. I would recommend that you take a look at the project models chapter in the modeling guide and some of the sample project models, especially the one from Richardson and Pugh, that come with Vensim. There is a lot of overlap in concepts and it might be easier to add to an existing model rather than start from scratch.