Ventana software support forum

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, This is the final message from the System Dynamics Mailing list. It has been great fun to watch the discussion over the last decade. To continue the conversation, please go to the forum at http://www.systemdynamics.org/forum I addition to the disc...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, I am sorry that this took so long. I have put in place a new forum that I hope will allow more flexible and complete communications. This is done as a PhpBB bulletin board and is located at: http://www.systemdynamics.org/forum Everyone can read th...

Posted by Bob Eberlein <bob@vensim.com> Dr David Lane (Operational Research Group and Managerial Economics & Stra= tegy Group) has received a teaching excellence award for his course =91System = Dynamics Modelling=92, after students on the Masters degrees in both Operational R= esearch and Decis...

Posted by Bob Eberlein <bob@vensim.com> Congratulations to the team on this. ----------- From: John Sterman <jsterman@MIT.EDU> Jack Homer, Drew Jones, and Gary Hirsch are three long-time SD people involved in this. Note particularly that the entire team decided to donate the full prize to support fu...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, Just a few comments on the recent posts on this thread - it is one that has had a variety of subthreads but I have kept the same heading to give some continuity. There have been some good suggestions around professional activities. But many of the...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, A note via John Sterman. Bob Eberlein ---------------------------- Below a post-doc opportunity combining system dynamics, behavioral economics, and other methods to study how communities respond to disasters, both natural and man-made (e.g., terr...

Posted by Bob Eberlein <bob@vensim.com> The obvious answer to Khalid's post is that the positive connections from economic prosperity to population growth work through mortality and not fertility. Better economic conditions lead to longer lives, hence more people. This, unfortunately, does not lend ...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, The System Dynamics Wiki is now open for input at http://www.systemdynamics.org/wiki To edit you will need to log in using the email and the password that you use with the web submission system. If you have not logged into the web submission syste...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, This discussion is interesting, but seems to have a lot of force in a direction I consider extremely misleading, if not simply wrong. First, the whole concept of a stock, level or state variable is an abstraction, so there is no absolute test of a...

Posted by Bob Eberlein <bob@vensim.com> Hi Jack, The change files that comes with Vensim for the 03 World3 model actually correspond to the 93 version of the model (and book) - perhaps some are even the original book. There are 13 of them corresponding to the 13 alternative scenarios in the earlier ...

Posted by Bob Eberlein <bob@vensim.com> Hi Tom, Let me clarify a little bit my points which were not well articulated. First, people are talking about at least two different things in this thread. The intent of the original post was to ask if we can find a criteria that will allow us to actually loo...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, Tom Forest wrote: > Where are our policy levers for this problem? I am not sure I see this as a problem, so much as an opportunity. And where I think it directly applies is in the creation of a library, if I may use the term loosely, of models add...

Posted by Bob Eberlein <bob@vensim.com> Richard's query puts standards in a very interesting light. Both on the list and off there have been lots of discussions of model quality and standards. However, what Richard is suggesting is a very basic set of guidelines that are meant to ensure the ability ...

Posted by Bob Eberlein <bob@vensim.com> What Monte described strikes me not so much as a policy paradox as an implementation dilemma. It is definitively not unique to System Dynamics or even to the social systems. For example, we can make a pendulum swing more quickly by increasing gravity. For a ph...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, The new dues structures was discussed at the conference this summer and formally announced in the September Newsletter. The intent was to give membership access to individuals who would not otherwise be able to afford it while not significantly im...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, I got a note from Hartmut Bossel that his books are now available in English. Details below. Bob Eberlein SYSTEM ZOO PUBLICATIONS by Hartmut Bossel http://www.hartmutbossel.de All English language books and CDs are available in internet and local ...

Posted by Bob Eberlein <bob@vensim.com> A short comment on this. There is a lot of discussion of data in this thread but as I understand from the original query data was intended to mean all information about the problem domain, the people involved, what is at stake, how information is exchanged and...

Posted by Bob Eberlein <bob@vensim.com> In a private communication Owen Ambur (Co-Chair of the StratML COP http://xml.gov/stratml/index.htm ) wrote: > Bob & Richard, it seems to me the ""place"" in which to ""bring together"" > ""suggestions for ...

Posted by Bob Eberlein <bob@vensim.com> Mr. Stevenson is correct in saying that he has put forward some suggestions for things it would be good to have - my apologies. I thank him for bringing these together into one place. There are none of that I would disagree with and I hope that people within t...

Posted by Bob Eberlein <bob@vensim.com> I gave Mr. Stevenson's post a constructive title, as I assume his intent was too look for good suggestions to move forward and not simply to criticize the status quo. I spoke with Jay after his speech on the next 50 years at the conference and told him I shoul...

Posted by Bob Eberlein <bob@vensim.com> This is wonderful news about Dynamica. That, along with D-memo's, some conferenc proceedings and of course back issues of the System Dynamics Review give us a very significant archive of historic work in the field. With the help of technology, much of this wor...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, I know some of us are still a little bit confused by Jack Homer's correct assertion that the average age of material in a stock and the outflow age are the same. The confusion comes because it is often easiest to think of a stock as getting distin...

Posted by Bob Eberlein <bob@vensim.com> Bill Harris and I had a small exchange on this. Bill points out that many style guidelines push away from capilization in a case such as this (psychology, economics, quantum physics, mathematics - none use caps). But psychologists study psychology, economists ...

Posted by Bob Eberlein <bob@vensim.com> Hi Everyone, A number of people have mentioned that the new from headers do not seem useful. I tend to agree. A problem with the old headers was that using reply seemed to be sending a message to a person, when in fact it was going to the list. I have changed ...

Posted by Bob Eberlein <bob@vensim.com> Thanks Monte for pointing out the importance of reproducibility. The notion that two people faced with the same problem would create the same model and come to the same conclusion is, however, much stronger than that. An experiemnt is reproducible if other peo...