Ventana software support forum

> Which is better depends on the questions that you wish to answer. If you are > worried about manufacturing floor layout, machine scheduling, machine downtown > and the like use discrete modeling. Alternatively, if you want to relate > manufacturing to product development and marketing use SD. > > ...

George, I like the points, but I have a question. > The consulting industry mantra is "sell at the top." Often SD does not. If A change management course I went through emphasized that by talking about the need for "authorizing sponsors", followed by a cascading chain of "re...

> theory. Ive seen an MIT dissertation from a person whos name always > escapes me (Graham, I think, or was it Greene) which seemed to do in a > quantitative sense what Senges archetypes did in a qualitative sense: give > one some rules of thumb to use in place of detailed simulations. It was > base...

Tom, > scientific method. I actually had in mind a particular case in the SD > literature in which an excellent practitioner made 2 changes simultaneously > in a model, and attributed the outcome to the wrong one. This reminds me of an article I read on proofs in mathematics which pointed out that t...

Tom, I think your ideas of a informal (my word, not yours) code of ethics is a good one. However, > - thou shalt perform parameter change experiments one at a time Doesnt the field of design of experiments teach that factorial designs may be significantly more efficient than changing one parameter a...

Chris Trost wrote: > As a licensed professional engineer and SD practitioner, Im against any > form of professional accreditation for SD consultants! As a former engineer who chose not to seek licensing because it wasnt needed in my field, I resonate quite well with Chriss arguments. I do agree with...

George Richardson writes: > Bill asks if we cant model systems, apparently thinking that we can. ^^^^ There are too many of us "Bills" out here!. :-) That was another one. > Im so attached to this notion of problem focus that I cant imagine you > would not agree with it. (Have to admit to ...

Fred Nickols wrote: >Im thinking about trying to model the "behavior" of my companys business >environment. Specifically, the demand for higher education (the demand for Fred, If Im misreading your intent, then I apologize. One of the things I have read and experienced in what modeling and...

Bill Braun wrote: > Subject: REPLY leverage points (SD0997) > Can you expand on the Senge thought. Seems, on the surface, to fly in the > face of the influence of underlying structure and to perhaps run afoul of > some archetypes. As I recall (it was about a year ago), he was speaking after the pers...

Steve Nyland wrote: > Subject: REPLY leverage points (SD0991) > Couldnt help but respond to this one. If theres no commitment from > the top the potential for successful implementation drops > significantly. Reminds me of an old Greek saying....."the fish rots It sounds good. However, I just fi...

George, Thanks for your _very_ interesting posting! Besides some seemingly impressive data, you included some important philosophical reminders and (for me) new (or newly packaged) insights. > errors for a few of our models, over a ten year period, (sit down at this > point) have typically been in t...

You raise some very interesting points. > Differential equations are difficult, confusing, weak, and > unrealistic. They often mislead students as to the nature of systems. Thanks for saying this. While Ive studied ODEs and PDEs in school and used them some at work, I can remember feeling more comfo...

Benny Budiman writes: >advances in the fields. Many people share hopes that system dynamics >modeling can be used as flight simulators to help turn the PDCA wheel *** >in managing socio-economic systems. Id inject the word faster here (***). Weve used simulation in such systems to great advantage in...

One thought keeps coming back when I think of feed-back/-forward and "circular causal structures" (it says the right thing, but it doesnt yet flow naturally off the tongue :-). Feedback (and feedforward), as I learned about them as a former practicing electrical engineer, both seem to be u...

Jim and others talk about a collection of molecules being assembled. Are these available to the general public (yet)? I noticed Jims comment that he was hoping Pal Davidson or his group might put them on the Web, so that seemed to imply that they would become available in the future, but "hope ...

Gene, Here is the message I got from the developer of EGO when it first came out. Just as a note, Ive found it reasonably easy to use, and I like the fact that it manages causal loop diagrams, unlike iThink (but like PowerSim?). The primary difference Ive found is the lack of emphasis on exogenous v...

Ed Gallaher wrote: >SD modeling was designed primarily for continuous systems. The fact that >discrete toolboxes have been added to STELLA and others bothers me >somewhat. Not because they are incorrect, but Id like to see a *very >simple* software package available, with just the basic elements. St...

Wayne Wakeland wrote: > Heres what I do whenever I work on a model. I have a Word document > open that is based on a template developed by Ed Gallaher called > "Instant Manual." I toggle back and forth between STELLA and Word It seems to me I saw that template on the mailing list previousl...

George Richardson wrote: >I do not yet have the final word on the availability of Modelling for >Management in paperback. The publisher intends to send me a blurb to go I got your note the same day my hardback copy arrived! I really like what Ive seen so far; it brings some articles together Ive rea...

Jim Hines wrote: >(Are there any other test inputs that have this character? While I havent tried it in a classroom presentation, you could also pick a constant (i.e., no step) input at a level that doesnt match the initial conditions in all of the intermediate levels (that is, have a constant order...

Bob, >Bill, >I read your comment with great interest. Were working with small farmers in >production of sustainable coffee fields in remote Peru. The biggest problem >is getting a handle on how to induce farmers to develop an afinity to the >project... The experiment here is design a system that sub...

John brings up an important point: >rate of demand exceeds the growth of capacity. Such a condition cannot >continue for very long, as the growing number of people seeking SD help >and expertise grow frustrated by inadequate access to skilled people and >resources; as the excess demand causes inexpe...

Ed writes: >Next month they will be scratching their head and saying, "Boy, if I had >six round holes in the frame of my car, I could put this trailer hitch on >..... " So someone drills the holes for them and they say, "Thanks, I >dont know anything about cars!...." They STILL d...

Gene wrote: >than find a need and respond to it with the PC as the answer. Have we >attempted "to Sell" System Dyanmics rather than sell solutions to specific >problems, with System Dyanmics as the vehicle? Are we selling drill bits as >opposed to educating the customer that we have a nift...

Benny, >Has anyone seen similar experience? If so, what should we do to mitigate >the academic smell so that SD can get the senior managaments attention that >it deserves? I had a recent experience that I think was enlightening for me. I was proposing a possible solution to a financial control syste...