Search found 43 matches
- Thu Jul 17, 2008 7:13 am
- Forum: SD Mailing List Archive
- Topic: QUERY Society Strategy Development
- Replies: 127
- Views: 147170
QUERY Society Strategy Development
Posted by Bill Braun <bbraun@hlthsys.com> Richard Stevenson writes and emphasizes (in addition to other ground covered) the need for a professional focus. The question of academic versus professional seems to have descended into a conversation that demands that we choose the ox by which we do not wi...
- Sun Jul 13, 2008 6:50 am
- Forum: SD Mailing List Archive
- Topic: QUERY European 'Global System Dynamics Project'
- Replies: 13
- Views: 11715
QUERY European 'Global System Dynamics Project'
Posted by Bill Braun <bbraun@hlthsys.com> Richard Stevenson writes, ""If anybody here is really interested in developing the field of SD, then the sooner we ditch the SDS and replace it with a professional body, the better."" Such a tone has been your constant refrain. I find the...
- Tue Jun 24, 2008 6:57 am
- Forum: SD Mailing List Archive
- Topic: QUERY Society Strategy Development
- Replies: 127
- Views: 147170
QUERY Society Strategy Development
Posted by Bill Braun <bbraun@hlthsys.com> Jay redirects us with, ""When we have a clear picture of the desired future for the Society and the field of system dynamics, then there could be a concrete discussion of how to achieve that future."" I suspect, without knowing for sure, ...
- Mon May 12, 2008 6:14 am
- Forum: SD Mailing List Archive
- Topic: QUERY Open and Resolved Issues in SD
- Replies: 1
- Views: 3502
QUERY Open and Resolved Issues in SD
Posted by Bill Braun <bbraun@hlthsys.com> Jack Homer noted his dismay ""to see extended discussion of yet another question that was answered in our field decades ago..."" I found the statement thoughtfully provocative and it prompts me to ask (generously, not contentiously), what...
- Fri May 09, 2008 7:53 am
- Forum: SD Mailing List Archive
- Topic: QUERY Models, Problems and Systems
- Replies: 29
- Views: 103089
QUERY Models, Problems and Systems
Posted by Bill Braun <bbraun@hlthsys.com> John Weldon asks if the SD problem focus rule is deficient, citing some examples of systemic models that delivered results. Kim Warren, in response to Weldon, notes, ""I too have been puzzled by where this mantra of 'model the problem, not the syst...
- Mon May 05, 2008 7:23 am
- Forum: SD Mailing List Archive
- Topic: QUERY Limits to Growth Plan B
- Replies: 26
- Views: 29549
QUERY Limits to Growth Plan B
Posted by Bill Braun <bbraun@hlthsys.com> Stephen Wehrenberg asks, ""What structural conditions support the continued lack of buy-in? What policy levers or feedback loops might be added to that structure that might result in increasing that buy-in? What structure enables ""this k...
- Thu Apr 10, 2008 7:23 am
- Forum: SD Mailing List Archive
- Topic: QUERY SD Thought Problem
- Replies: 1
- Views: 3395
QUERY SD Thought Problem
Posted by Bill Braun <bbraun@hlthsys.com> I have a faint recollection of an archetypal story told in the context of an SD lesson. A person leaves home at random times but almost always has to wait at the crossing for a train (which is on a regular schedule) to pass. Does this ring a bell with anyone...
- Thu Apr 10, 2008 7:23 am
- Forum: SD Mailing List Archive
- Topic: QUERY Meaning of Stock/Level
- Replies: 46
- Views: 39303
QUERY Meaning of Stock/Level
Posted by Bill Braun <bbraun@hlthsys.com> Alan McLucas asks about soft variables and stocks. Interesting question. Imagine a group of people who work together and there are two cups on each person's desk labeled ""Trust"" and ""Doubt"". We start with ten chits...
- Tue Apr 08, 2008 7:15 am
- Forum: SD Mailing List Archive
- Topic: QUERY Who wants to share models
- Replies: 24
- Views: 23728
QUERY Who wants to share models
Posted by Bill Braun <bbraun@hlthsys.com> At the risk of dredging up the common file format conversation, this strikes me as a good reason for such a thing. I do get the sense that the absence of responses from the software writers on the idea of a common format is an indicator that they either stil...
- Mon Apr 07, 2008 7:14 am
- Forum: SD Mailing List Archive
- Topic: QUERY Who wants to share models
- Replies: 24
- Views: 23728
QUERY Who wants to share models
Posted by Bill Braun <bbraun@hlthsys.com> Martin offers a perspective on collaboration. Good points, all. In further thinking about Magne's question, and your thoughts also, I think it may be useful to distinguish between group model building and group model construction. There is much good thinking...
- Sun Apr 06, 2008 5:52 am
- Forum: SD Mailing List Archive
- Topic: QUERY Who wants to share models
- Replies: 24
- Views: 23728
QUERY Who wants to share models
Posted by Bill Braun <bbraun@hlthsys.com> SDMAIL Magne Myrtveit wrote: > In order to answer your question, I need to understand what is ment by > ""collaborative modeling for learning"". How a group might collaborate to write a paper is a good example. The ability to track change...
- Sun Apr 06, 2008 5:52 am
- Forum: SD Mailing List Archive
- Topic: QUERY Small Startup Business Models
- Replies: 1
- Views: 3263
QUERY Small Startup Business Models
Posted by Bill Braun <bbraun@hlthsys.com> A number of people have converted the archetypes to small models. All of them can be used prospectively from a planning point of view. While they are simple models, they might be the foundation for a deeper exploration of a particular start-up. Bill Braun Po...
- Thu Mar 27, 2008 7:20 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Jack asks if I have read the Dueling Loops paper (not seeing me use any key phrases) and notes that Sterman defines exogenous variables as arising ""from outside the boundary of the model."" (page 95) Thus all the variables in the model a...
- Mon Mar 24, 2008 7:13 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Jack writes, ""Thanks. I don't understand what you mean by ""pump different content through it."" What is ""it""? What is ""pump""? What is ""different content""? Also,...
- Sat Mar 22, 2008 6:47 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Jack Harich offers the Dueling Loop model as an example of root cause, and high and low leverage points. http://www.thwink.org/sustain/articles/005/DuelingLoops_Paper.htm I am curious about the high leverage points; they are both exogenous parameters (bottom...
- Thu Mar 13, 2008 6:57 am
- Forum: SD Mailing List Archive
- Topic: QUERY Open Source Simulation Software for SD
- Replies: 22
- Views: 22794
QUERY Open Source Simulation Software for SD
Posted by Bill Braun <bbraun@hlthsys.com> Len Malczynski, among many good points, says that as features vary across software vendors there would be mismatches between imports and exports, and wonders if such a move [to standard file format] might result in homogeneity of tools? Magne Myrtveit makes ...
- Tue Mar 11, 2008 7:20 am
- Forum: SD Mailing List Archive
- Topic: QUERY Open Source Simulation Software for SD
- Replies: 22
- Views: 22794
QUERY Open Source Simulation Software for SD
Posted by Bill Braun <bbraun@hlthsys.com> Len Malczynski opines that SMILE and XMILE formats will not be realized owing to software firms competing for our business. Assuming that markets are as rationale as our economist friends say, if the market asks for a common document format, the software pub...
- Mon Mar 10, 2008 7:23 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Ralf Lippold talks about surfacing mental models and opening them to challenge in the context of building shared vision. I've recently been facilitating conversations at work where the process is centered on the future people want. I've found that while the ...
- Mon Mar 10, 2008 7:23 am
- Forum: SD Mailing List Archive
- Topic: QUERY Open Source Simulation Software for SD
- Replies: 22
- Views: 22794
QUERY Open Source Simulation Software for SD
Posted by Bill Braun <bbraun@hlthsys.com> Jean-Jacques Laublé wrote that he could not read Powersim models and laments not having access to the equations. Perhaps a small rules change for paper submissions could help. If I am coming up against the page limit of the paper and still have stunningly br...
- Wed Mar 05, 2008 7:31 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Jack Harich opines that if the structure that produces the reference mode is the root cause, then there is no root cause, per se. I ought to have added that once the model is constructed, the high leverage policy or policies that (when changed, added, or del...
- Tue Mar 04, 2008 7:54 am
- Forum: SD Mailing List Archive
- Topic: QUERY Definition of root cause
- Replies: 34
- Views: 30356
QUERY Definition of root cause
Posted by Bill Braun <bbraun@hlthsys.com> Jack Harich asks about the definition of root cause. Broadly stated, it would be the structure that produces the reference mode up to the present and, if policies were left as is, would result in the ""feared"" mode in the future. Bill Br...
- Wed Feb 20, 2008 7:51 am
- Forum: SD Mailing List Archive
- Topic: QUERY The Minimum Acceptable Model Standard
- Replies: 18
- Views: 17029
QUERY The Minimum Acceptable Model Standard
Posted by Bill Braun <bbraun@hlthsys.com> Would an open source authorship approach to this be feasible? It offers the possibility of moving beyond the limitations that Tom Forest cites. I am not knowledgeable about the technology used for such an initiative. If there is energy around the idea, I'll ...
- Thu Jan 10, 2008 7:18 am
- Forum: SD Mailing List Archive
- Topic: ANNOUNCE Submission System Open/Athens Conference
- Replies: 1
- Views: 4111
ANNOUNCE Submission System Open/Athens Conference
Posted by Bill Braun <bbraun@hlthsys.com> Thank you to all that responded. I hope I captured everyone's contributions. Bill Braun - - - - SOFTWARE AnyLogic http://www.xjtek.com/ Arena http://www.arenasimulation.com/ CACI SimProcess http://www.simprocess.com/downloads/downloads.cfm Will run with Vens...
- Fri Jan 04, 2008 8:47 pm
- Forum: SD Mailing List Archive
- Topic: QUERY Discrete event software (002)
- Replies: 13
- Views: 11344
QUERY Discrete event software (002)
Posted by Bill Braun <bbraun@hlthsys.com> I am involved in a project where I may need to contrast SD and discrete event simulation. I want to avoid significant investment until the future path becomes clear. I would appreciate suggestions/recommendations on open source and/or low cost packages. The ...
- Mon Dec 17, 2007 5:52 am
- Forum: SD Mailing List Archive
- Topic: QUERY Policy paradox and SD
- Replies: 21
- Views: 23133
QUERY Policy paradox and SD
Posted by Bill Braun <bbraun@hlthsys.com> Bill Harris wrote: > Sometimes I think accountability is used synonomously with punishment > or the threat of punishment. Hi Bill H., Forgive me for taking a single sentence out of context. I think you are right on the mark and it summarizes my mental model ...