Ed Roberts once told me that he introduced causal loops.
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
Search found 80 matches
- Mon Dec 14, 1998 8:50 am
- Forum: SD Mailing List Archive
- Topic: Who introduced causal-loop diagrams
- Replies: 3
- Views: 5455
- Fri Nov 20, 1998 9:18 am
- Forum: SD Mailing List Archive
- Topic: Fisheries Management
- Replies: 1
- Views: 9704
Fisheries Management
Jody House and Babette Wils, working with Dana Meadows, have done very
interesting work on the Shrimp industry (wild caught and culture). Their
emails are JHouse@MIT.EDU and wil@vassar.edu (maybe, wils@vassar.edu).
Regards,
Jim Hines
From: Jim Hines <jimhines@interserv.com>
interesting work on the Shrimp industry (wild caught and culture). Their
emails are JHouse@MIT.EDU and wil@vassar.edu (maybe, wils@vassar.edu).
Regards,
Jim Hines
From: Jim Hines <jimhines@interserv.com>
- Sat Nov 14, 1998 11:22 am
- Forum: SD Mailing List Archive
- Topic: Modelling Manufacturing Systems
- Replies: 2
- Views: 10357
Modelling Manufacturing Systems
John Morecroft (Professor, London Business School) has done work in
these areas. His doctoral dissertation was on MRP. Influences from
Information Technology on Industry Cycles, 1979, M.I.T.
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
these areas. His doctoral dissertation was on MRP. Influences from
Information Technology on Industry Cycles, 1979, M.I.T.
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
- Sat Nov 14, 1998 11:16 am
- Forum: SD Mailing List Archive
- Topic: Whole Systems
- Replies: 7
- Views: 17703
Whole Systems
Nugent, Michael D wrote: > Question (not criticism): > When the focus is profits, why would not a systems (e.g., a > businesss) suppliers and customers and regulators (and international > economic cycles, emerging technology, etc.) be included in "everything we > believe must be included in ord...
- Tue Nov 10, 1998 11:52 am
- Forum: SD Mailing List Archive
- Topic: modeling systems
- Replies: 6
- Views: 18397
modeling systems
Bill Buchanan wrote: .
> ...Of course whole "systems" can be modeled. ... Examples abound,
People on this list would disagree that any of your examples is a "whole" system.
Regards,
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
> ...Of course whole "systems" can be modeled. ... Examples abound,
People on this list would disagree that any of your examples is a "whole" system.
Regards,
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
- Fri Nov 06, 1998 10:44 am
- Forum: SD Mailing List Archive
- Topic: Systems of problems
- Replies: 5
- Views: 7829
Systems of problems
Bill Braun wrote "...Akoff said that one aspect of applying systems thinking was to think in terms of systems of problems...If SD is best suited to exploring problems, and problems are considered from an interlocking, interdependent systemic point of view, why is it not reasonable to model larg...
- Tue Nov 03, 1998 2:02 pm
- Forum: SD Mailing List Archive
- Topic: College drinking
- Replies: 8
- Views: 10284
College drinking
Khalid, Im not clear on what goal is sliding. The drinkers goal remains to be socially at ease. Also, as much as we would like to think that drinkers are social outcasts, Im not sure thats the case. An unfortunate process might involve a positive loop in which drinking becomes increasingly acceptabl...
- Fri Oct 30, 1998 9:28 am
- Forum: SD Mailing List Archive
- Topic: College drinking
- Replies: 8
- Views: 10284
College drinking
Van Bowen, What is the reference mode? I think it is that college drinking (and use of drugs) is and has been high for decades. Why? (Alternatively, it could be that **concern** about college drinking is rising -- why?). If the issue is college drinking itself: I think that one dynamic hypothesis is...
- Thu Oct 22, 1998 9:08 am
- Forum: SD Mailing List Archive
- Topic: Object Orientation Challenge in S/W Projects Management & SD
- Replies: 3
- Views: 5907
Object Orientation Challenge in S/W Projects Management & SD
Id approach this by starting with the project model and considering how OO would impact it. For example, productivity and quality of a new component would probably be low, while productivity and quality for reuse would be high. The functions relating fatigue to its effects on productivity and qualit...
- Wed Oct 07, 1998 10:12 am
- Forum: SD Mailing List Archive
- Topic: Validity of Models
- Replies: 4
- Views: 6989
Validity of Models
This is a response to John Gunklers thoughtful posting (1) I predict that the word "prediction" is going to cause problems in this discussion. Some people (like me) think of it as meaning "point prediction", others (like David Peterson) think of it as meaning any statement about ...
- Wed Sep 16, 1998 1:37 pm
- Forum: SD Mailing List Archive
- Topic: Subsriber Development for Internet Service Providers
- Replies: 3
- Views: 9831
Subsriber Development for Internet Service Providers
Berhnhard,
Diffusion type models would probably be quite relevent.
Jim Hines
MIT
From: Jim Hines <jimhines@interserv.com>
Diffusion type models would probably be quite relevent.
Jim Hines
MIT
From: Jim Hines <jimhines@interserv.com>
- Tue Sep 15, 1998 12:49 pm
- Forum: SD Mailing List Archive
- Topic: Work on Water Resources
- Replies: 4
- Views: 13683
Work on Water Resources
Abdul,
Could you be more specific? What issues are you interested in? What
reference modes?
Regards,
Jim Hines
From: Jim Hines <jimhines@interserv.com>
MIT
Could you be more specific? What issues are you interested in? What
reference modes?
Regards,
Jim Hines
From: Jim Hines <jimhines@interserv.com>
MIT
- Tue Sep 15, 1998 12:46 pm
- Forum: SD Mailing List Archive
- Topic: The Hard Core of SD
- Replies: 7
- Views: 7744
The Hard Core of SD
Concerning George Richardsons reply:
Well, gosh, George, tell us what you SAID in all of those places.
Jim
From: Jim Hines <jimhines@interserv.com>
Well, gosh, George, tell us what you SAID in all of those places.
Jim
From: Jim Hines <jimhines@interserv.com>
- Fri Aug 28, 1998 11:38 am
- Forum: SD Mailing List Archive
- Topic: international trade models
- Replies: 3
- Views: 5953
international trade models
Jeff, It would help us a lot if you could be a bit more specific about your SD focus on international trade in maize. You might want to give us a key reference mode: Is your issue, for example, that trade has been declining (or growing or stagnating)? Is it that prices have been rising (or falling o...
- Wed Aug 19, 1998 11:50 am
- Forum: SD Mailing List Archive
- Topic: systems or reference modes?
- Replies: 3
- Views: 6297
systems or reference modes?
Drews more specific statement of the forest problem should serve as an example for us all. There are several ways to get specific, reference modes are one of the best. Drew asks: "It is well accepted that the "model the system" trap is a particularly nasty one, but does the same lesso...
- Tue Aug 11, 1998 1:44 pm
- Forum: SD Mailing List Archive
- Topic: SD Self-Study Curriculum
- Replies: 4
- Views: 6852
SD Self-Study Curriculum
This is a response to Bill Brauns request for thoughts on self-study. There are a number of possibilities. But, first your statement: >I sense that I am particularly ill prepared from an algebraic >point of view. A facility with algebra is necessary for modeling. If you havent used algebra, for awhi...
- Mon Aug 10, 1998 9:15 am
- Forum: SD Mailing List Archive
- Topic: Application of SD to Risk Manageme
- Replies: 8
- Views: 8840
Application of SD to Risk Manageme
A short build on Bob Eberleins excellent point that multivariate sensitivity analysis can help us ".. see whether there are combinations of parameters that put the model into different behavior regimes." Bob says this "allows you to have more confidence...". It also may guide you...
- Thu Jul 30, 1998 10:59 am
- Forum: SD Mailing List Archive
- Topic: Systems from the top?
- Replies: 26
- Views: 55012
Systems from the top?
Just a clarification to Jay Forrests comments: > >3) How to "sell" the conclusions of an SD process to the rest of a > >company. Jay wrote: > As a facilitation oriented consultant, I believe "selling" the conclusions > includes connotations which doom the consultation. The need t...
- Mon Jul 27, 1998 9:17 am
- Forum: SD Mailing List Archive
- Topic: Systems from the top?
- Replies: 26
- Views: 55012
Systems from the top?
This is a reply to Van Bowen, who asked > Does anyone have information concerning > system dynamics being the way of thinking at all levels of > any company? You have put your finger on the current challenge in applied SD. Its no longer unusual to find a SD project being done at a (large) company. H...
- Mon Jul 27, 1998 8:38 am
- Forum: SD Mailing List Archive
- Topic: models of forests and forest economies
- Replies: 4
- Views: 6208
models of forests and forest economies
This is a reply to Drew Jones posting, and is only offered because Drew is such a terrific SDer and should be setting the pace for the rest of us! Drew wrote: >We are seeking system dynamics models that investigate: > >1. the dynamics of forests, and/or >2. the interactions between forest ecosystems...
- Thu Jul 09, 1998 10:42 am
- Forum: SD Mailing List Archive
- Topic: System dynamics in K-12 education
- Replies: 9
- Views: 9284
System dynamics in K-12 education
Concerning Guenther Ossimitz interesting post about his investigation
into the difficulties that 14 and 15 year olds have with SD:
A control group of adults would have been interesting. My guess is
that adults have the same difficulties.
Regards,
Jim Hines
LeapTec and M.I.T.
JimHines@Interserv.Com
into the difficulties that 14 and 15 year olds have with SD:
A control group of adults would have been interesting. My guess is
that adults have the same difficulties.
Regards,
Jim Hines
LeapTec and M.I.T.
JimHines@Interserv.Com
- Mon Jun 29, 1998 9:04 am
- Forum: SD Mailing List Archive
- Topic: Causal Loop Diagraming Tool
- Replies: 7
- Views: 10358
Causal Loop Diagraming Tool
Vensim can create neat causal loop diagrams (as well as stock and flow
diagrams). Also, you can create simulation models from causal
loops,from stock and flows, or any mixture of the two formats.
Regards,
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
diagrams). Also, you can create simulation models from causal
loops,from stock and flows, or any mixture of the two formats.
Regards,
Jim Hines
MIT and LeapTec
From: Jim Hines <jimhines@interserv.com>
- Sat Apr 25, 1998 5:54 pm
- Forum: SD Mailing List Archive
- Topic: Published, quantifiable results
- Replies: 2
- Views: 6446
Published, quantifiable results
Fabian H. Szulanski wrote: > > Hello Chris, > There is one case that I recall, it is related with a legal battle > between the US State and a ship building company called Halter Marine, The original work was done by Pugh-Roberts and involved building a project model to support a claim by Halter Mari...
- Sat Apr 18, 1998 10:45 am
- Forum: SD Mailing List Archive
- Topic: Some questions Re:accreditation
- Replies: 9
- Views: 23362
Some questions Re:accreditation
Alans thesis is wonderful. You might be interested in knowing that Alan is with Pugh Roberts. In addition to being one of the leading system dynamics folks he is also an expert in TQM (and has a relatively recent book out in that field). If you liked Alans thesis, you might also be interested in Nat...
- Thu Apr 16, 1998 10:45 am
- Forum: SD Mailing List Archive
- Topic: Some questions Re:accreditation
- Replies: 9
- Views: 23362
Some questions Re:accreditation
Actually I liked Toms injunction to - thou shalt perform parameter change experiments one at a time. Changing parameter values one at a time is directed not toward getting confidence bounds, but rather toward understanding the model. The injunction should probably be: - thou shalt take the time to u...