Ventana software support forum

hi, validating a system dynamics diagram without simulation has in our experience never payed out unless in reinforcing (erroneous) preconceptions. For this we think are responsible two reasons: 1. the role of levels comes out only in simulation 2. real world models are almost without exception high...

just one remark: in my personal experience on the real stock markets the difference is speed or delay between perceived market infos and real market situations for succcess of a transaction. // yours sincerely ulrich la roche fast focus consulting heilighuesli 18, CH-8053 Zuerich, switzerland fax +4...

see 94 ISDC papers: Is there a cause-effect relationship between unemployment and taxation level ? by ulrich la roche on request a tested and functional powersim model is available. (one of our free for take working and tested gadgets in our consulting work: theme organisational environments) // you...

for a "hard" simulation approach including costing look at the example at www.rhone.ch/fastfocus/ with demo download. english version soon to follow. // yours sincerely ulrich la roche fast focus consulting heilighuesli 18, CH-8053 Zuerich, switzerland fax +411 382 1349 From: ularoch@ibm.net

download an exemple of a budget-managment tool "BB-TOOL"
www.rhone.ch/fastfocus/
an eventual english version is in preparation.

// yours sincerely ulrich la roche
fast focus consulting
heilighuesli 18, CH-8053 Zuerich,
switzerland
fax +411 382 1349
From: ularoch@ibm.net

my advice is: first concentrate on understanding the problem. in my quite long professional life i have learned to consider neural networks as rather last ressort, then good starting point.... // yours sincerely ulrich la roche From: ularoch@ibm.net fast focus consulting heilighuesli 18, CH-8053 Zue...

yes i did,
pls refer to utrecht SDC 92 paper titled
system dynamic analysis, a prototyping tool for production system design

// yours sincerely ulrich la roche
From: ularoch@ibm.net
fast focus consulting
heilighuesli 18, CH-8053 Zuerich,
switzerland
fax +411 382 1349

comment on the problem of tragedy of the commons: in our own experience for business models, if ever a problem of tragedies of the commons appears, this is a sure indication, that the business segmentation is not done correctly. so instead of treating a problem of the tragedy of the commons, we advi...

treating whole businesses top down is just one of our main activities. however it is predominantly not systems thinking but systems analysis aided by isomorphic process models that are simulated (just what jay forrester did pioneer and describe in his still up_to_date book "industrial dynamics&...

a robust model: since stock and flow atoms do have strongly nonlinear characteristics if modelling real world business, a prerequisite to have a robust realistic model is validatation right at atom level. we are aware that this does not fit well with the idea of "same structure, same behaviour&...

hi bob, hi everybody, from the humble workplace of practical business simuation we do have a sligthly different view on models and optimation. first the models represent real process-chains second the problem to be solved is how to control (steer) for best margin and deliverability, or other involve...

hi, maybe the paper in proceedings isdc 92 utrecht page 355 ba u. la roche will give a useful overview guiding further research into the question. the principal world views using simulation are compared: -next event -activity scanning -process interaction - transaction flows // yours sincerely ulric...

even in nonlinear control theory it is concluded, that optimizing subsystems only is a sure way of not reaching the overall optimization possible. beeing a zynic i conclude, that a "good" consultant tries to have always some work left over....hence only advising work with subsystems. using...

efficiency or other global parameters of a process are to our experience much easier modelled and simulated with stocks, flows and explicit controls than by discrete-event. you get a direct behavior output instead of statistics evaluation. one does the work in control-system space (continuous) rathe...

hi, we as other professional sd-people are selling and developping appropriate sd-based tools for business planning and simualtion. these should do the job required. ours is called BB-TOOL (registered trademark) and is a universal process-knot, which can be individualised by 40 parameters including ...

chaos in supply chains? you bet this is just to indicate, that in our own work for business-process-control as in all the practical business cases we had, avoiding chaos by proper and optimized process-chain-control is what SD-applications do best. keywords would be: push, pull, kanban and backward ...