Search found 14 matches

by =?iso-8859-1?Q?Andr=E9_Reichel?=
Mon Nov 24, 2003 3:00 pm
Forum: SD Mailing List Archive
Topic: What do you mean by the term mental model?
Replies: 5
Views: 13298

What do you mean by the term mental model?

0 Hi Jim, in a wider sense I would regard a "mental model" as a map of the world made up from and in front of our cognitive structures. These structures are twofold: (1) They are based on past experiences on the world and assumptions about how and why it works in the way it does. This is a...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Thu May 29, 2003 3:26 pm
Forum: SD Mailing List Archive
Topic: Epistemologic question
Replies: 5
Views: 5477

Epistemologic question

Antoni wrote: In some way the model is created by the problem. Is that right? What are the epistemologic consequences of this way of doing? Knowledge is always, an maybe first of all, problem solving knowledge. The process of gaining knowledge (learning) is an explanatory process, aimed at solving a...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Mon Apr 22, 2002 9:45 am
Forum: SD Mailing List Archive
Topic: Economic Dynamics
Replies: 3
Views: 4030

Economic Dynamics

Mabel wrote: | a market stock becomes completely depleted. The | economic model has no need to maintain a backlog | because (being an economic model) shortages or | excesses of goods are adequately expressed in a | commoditys value. But the model does need to If there is no backlog of "waiting&...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Thu Apr 18, 2002 2:54 pm
Forum: SD Mailing List Archive
Topic: SD Models from Written Text
Replies: 30
Views: 28199

SD Models from Written Text

Hi all, I was glad to read the comments by Lazaros about this topic after all these very enthusiastic postings. A software tool for extracting a SD model out of textual description would indeed benefit only the expert model builder (I dont regard myself as one) just as iconographic SD software. Afte...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Wed Apr 17, 2002 5:07 pm
Forum: SD Mailing List Archive
Topic: Modeling Anticipation
Replies: 8
Views: 14072

Modeling Anticipation

Bill Braun wrote: | Can forecasts of the future be dynamically modeled, with information from | stocks (that represent a future state) feeding back into current decisions? Let me get this straight: you ask for a reversed prediction tool. A model that derives the current state of stocks from their fu...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Tue Apr 16, 2002 9:31 pm
Forum: SD Mailing List Archive
Topic: Representing constraints
Replies: 30
Views: 43682

Representing constraints

Niall wrote: | using such quantum devices, but rather to inquire whether the idea of | nonlocality might have _any_ kind of application outside physics. In | essence, I wanted to know whether it is ever, under any circumstances, | justifiable to neglect interaction time in mutual interactions. The |...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Tue Apr 09, 2002 6:44 pm
Forum: SD Mailing List Archive
Topic: SD Models from Written Text
Replies: 30
Views: 28199

SD Models from Written Text

Hello all, this topic has developed into another major talk about the nature of SD. The original question was about extracting a model from a verbal statement. The transformation of a problem context into such a verbal statement is, of course, model building as well. So, regardless what instruments ...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Sat Apr 06, 2002 8:25 pm
Forum: SD Mailing List Archive
Topic: General Utility Problem
Replies: 0
Views: 2994

General Utility Problem

Hello all, maybe some of you remember the mentioning of the SFEcon model in an earlier thread. Ive engaged into a discussion on their message board at http://www.sfecon.com/BBoard/wwwboard.shtml The main purpose of the SFEcon model is to solve the General Utility Problem. It uses a non-linear matrix...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Sat Apr 21, 2001 6:20 pm
Forum: SD Mailing List Archive
Topic: A causes B
Replies: 14
Views: 27497

A causes B

The question how can we uncover causation is a tricky one. New and uncommon problems are not likely to reveal the true causation of things to us. We can use, like Mark suggested, the scientific method to develop a hypothesis about what is going on for what reasons, and test it. How do you develop a ...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Fri Apr 20, 2001 7:56 pm
Forum: SD Mailing List Archive
Topic: The order of a system
Replies: 16
Views: 10655

The order of a system

Hello, Niall wrote: "x = A.sin(kt) + B.cos(kt) This model has no stocks whatsoever - it isnt really a dynamical system at all, since it has no integrals, yet it behaves in exactly the same way as the 2nd-order spring system x = -k^2.x - (S1) So is this a zero-order model, or a 2nd-order model, ...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Wed Apr 18, 2001 5:46 pm
Forum: SD Mailing List Archive
Topic: The order of a system
Replies: 16
Views: 10655

The order of a system

Hello, before I start I must admit that my skills in maths are roughly about average. Nevertheless, the questions asked by Niall made me grab some math textbooks and the remainders of my SD courses. Here is what I came up with (which might be completely wrong but maybe good enough to start a discuss...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Wed Apr 11, 2001 10:51 am
Forum: SD Mailing List Archive
Topic: Unwarranted Criticism
Replies: 16
Views: 21397

Unwarranted Criticism

Hello all, Ted made some good points about some of my earlier comments on this topic. The reference mode should always tried to be sketched over time. This is a very essentiel first step and it clarifies your dynamic hypothesis about the systems behavior. If you have historical data then this refere...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Sun Apr 08, 2001 3:27 pm
Forum: SD Mailing List Archive
Topic: Unwarranted Criticism
Replies: 16
Views: 21397

Unwarranted Criticism

Hello all, it is true that SD does not rely too heavy on "empirical evidence or previous knowledge of the subject". SD-models look not so much for parameters, time-series or statistical data like other methods (especially econometrics). The view of SD is a structural view. This means that ...
by =?iso-8859-1?Q?Andr=E9_Reichel?=
Sun Apr 08, 2001 2:09 pm
Forum: SD Mailing List Archive
Topic: Electricity Regulation/Deregulation
Replies: 7
Views: 11123

Electricity Regulation/Deregulation

Hello all, Jaideep raised some interesting questions which are not easy to answer. I personally think, system dynamicists saw this thing coming. Why did nobody listen? I can merely guess but this is truly a high political issue. Instead of browsing what went wrong or whos fault it might be, lets thi...