February 1997

Date: Thu, 6 Feb 1997
From: Eric Sweiven (SWEIVE@VAX1.MANKATO.MSUS.EDU)
Organization: Open Air
To: SysDyn Discuss Group (K-12SD@SYSDYN.MIT.EDU)
Subject: Looking for Joan Yates

Hello,

I am a graduate student studying Experiential Education and its connection/corelation with sys dyn and sys think.

I am wanting to reach Joan Yates to talk to her about her paper"Quality and System Dynamics..." I just recently came across it in the CLE's archives and I am intrigued by some of her points.

Is Joan a subscriber, if not does anyone know her email address?

I have corresponded once with Nan Lux concerning the interest and happenings in the sys dyn area here in California. I am a bit ashamed to admit I lived in Arizona (Prescott) for five years and never heard about what the Orange Grove school was doing...

Does anyone have any insight as to recent developemtns in California? What about Bela Banathy's work, has anyone looked at the relationship between his ideas and Forrester's? I have never seen him mentioned in any of the articles/papers? Is anyone familiar with his writing?

Thanks for any help,

Eric Sweiven

Date: Sat, 8 Feb 1997
To: k-12sd@sysdyn.mit.edu
From: Jeff Dooley (DOOL@CONCENTRIC.NET)
Subject: Introduction

Hi everyone,
Nice to be here. I have two hats: First, I'm a systems consultant and educator struggling to embody systems principles in ways relevant to the everyday problems and issues that face people today. Second, I'm a parent of two small children. My oldest is just entering her elementary education experience this year.

I'm really gratified to see that so many people are working to bring systems principles into elementary education. I hope our conversation can help us learn more about what great things are already being done, and make us more effective in widening the scope and relevance of systems education.

Best wishes, Jeff Dooley

Jeff Dooley
Adaptive Learning Design
Petaluma, CA 94952
707-762-1460 voice
707-762-1429 fax
dool@concentric.net
dooley@well.com
http://www.well.com/user/dooley/

Date: Tue, 18 Feb 1997
To: k-12sd@sysdyn.mit.edu
From: "Bryant C. Vernon" (DOSTOEVSKY@RUSSIAMAIL.COM)
Subject: Problems with the K-12sd list

Hello, k-12sd List,

Our server for this K-12 list has been acting improperly the past few weeks. Some people have been inavertantly deleted. Also, the entire list has been receiving requests to subscribe and unsubscribe without our knowing it was happening

. We are working to bring things under control.

Please remember that messages to subscribe to the list or unsubscribe should NOT be sent to the K-12sd@sysdyn.mit.edu list. Doing so causes them to be sent to everyone on the list. Such messages clutter many mailboxes and cause people to be unhappy.

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In the meantime, we ask your patience as we work toward an interesting, informative, and smooth-running list for us all.

Nan Lux, Administrator, k-12sd
Program Manager, System Dynamics Group
E60-383, 30 Memorial Drive, Cambridge, MA 02139
Phone: (617) 253-1574 Fax: (617) 252-1998
Email: nlux@mit.edu

To: k-12sd@sysdyn.mit.edu
From: "A.T.S." (CCT18@ROCKWOOD.K12.MO.US)
Subject: dt QUESTION
Date: Thu, 20 Feb 1997

My name is Art Schneiderheinze at the Center for Creative Learning in St. Louis, Missouri.

#1:
My students are analyzing the dynamics of systems inside theme parks ---specifically the flow of people over the course of a day.

As a result, we set the dt for our models at 0.25 HOURS.

Using this time works well for our models --- until we want to change, say, the COOKTIME of an oven stock to represent the amount of time it takes, say, to check out a person in a gift shop.

If, say, the amount of time to check someone out is 2.5 minutes, how would you put this in as the COOKTIME for the oven stock? The stock represents the number of people currently at the register in the gift shop. The outflow from the oven is determined by the COOKTIME.

If the dt is 0.25 HOURS (or 15 minutes), how is 2.5 minutes represented as COOKTIME?

Any ideas?

#2:
Anyone know how to print a STELLA model to a printer so that it fits all on one page? I am using a Windows PC machine... and whenever we print, it always takes two pages. I would like for my kids to take their models to discussion groups. It would be easier to analyze on one sheet of paper instead of two. Any ideas?

#3:
Anyone know how to have the title of a graph show up on a printout? We get great looking graphs and tables, but it would be easier for my kids to have a TITLE on the printout. Any ideas?

#4:
Anyone doing anything dynamic to help kids understand how IF-THEN statements work? My kids can understand the logic part... but they get confused in a statement like this:

IF (Cars_in_Parking_Lot) spaces_available THEN (Cars_Ready_to_Park) ELSE (0)

They understand the logic of this... but struggle with the idea that ALL cars ready to park move as a group (as dependent on dt). Any ideas on how to make the whole idea more clear to 4th/5th graders?

Thanks!

ART SCHNEIDERHEINZE
Rockwood School District
Center for Creative Learning
265 Old State Road
Ellisville, MO 63021
cct18@mail.rockwood.k12.mo.us

Date: Fri, 21 Feb 1997
To: "A.T.S." (CCT18@ROCKWOOD.K12.MO.US)
From: Fabian Szulanski (FABIANS@IFI.UIB.NO)
Subject: Re: dt QUESTION Cc: k-12sd@sysdyn.mit.edu

Art,
I'm Fabian Szulanski, currently in the Master in System Dynamics at the University of Bergen, Norway

Some hints: (I'll answer each of your questions)

#1:(dt,simulation time, Cooktime) Integration of the differential equations within Stella usually converge to a single value when dt tends to 0, so you shouldn't have problems in define dt = 0.25 minutes instead of 0.25 hours.You should simulate then (for example if your theme park is open from 10am to 8pm, which is a 10 hours period of time) from 0 to 600 minutes.In this case, your cooktime would be of 2.5 minutes.If you wish to use hours as the overall time units in your model, then choose dt = 0.0041666667 hours (0.25 minutes), and simulate from 10 to 20 hours (8pm), and set your cooktime to 0.041666667 hours (2.5 minutes).In my opinion it's simpler to use minutes as the overall time unit in this case, but of course it depends on the speed of your computers.Assess your resources, and make a decision.

#2:(printing models) Is a matter of design, with some limitations: try to design your model structure so it fits in width in one page, then go downwards.You can use the ghost object for trying to make your model fit the width of one page, but you may lose continuity in your structure, and might find it difficult to trace causal feedback loops.Of course the obvious solution is to keep your model structure as simple as possible, but not always this is the case, sometimes you want to portray more pieces of structure that reflect your hypothesis about the problem you're analyzing.Weight the trade offs, and decide.

#3:(graph titles) Did you try attaching a text object close to the graph, with the title written in it?

#4:(dynamic if-then) One possible suggestion:Use any continuous process, such as a bathtub filling and overflowing, to make them understand the characteristic of a continuous process, and that the continuous flow goes from one stage to the other (from inside the bathtub to the overflow) after fulfilling a conditional clause :if water in bathtub is greater than MaxCapacity then overflow.Try to include the simple stock and flow diagram with animation of the two levels (one for the bathtub and one for the overflow).By analogy and knowledge transfer, they should understand the if then clauses within the theme park.The simpler the example, the better.

Hope I've helped a little.
Best Regards.

Fabian.

Date: Fri, 21 Feb 1997
To: k-12sd@sysdyn.mit.edu
From: Fabian Szulanski (FABIANS@IFI.UIB.NO)
Subject: Little correction

Dear fellows,
A little correction:
In my answer to question #1 of A.T.S., the simulation time will be the same.It will change if instead of choosing 0.25 minutes as dt, ATS chooses 15 minutes as intended.Try different dt, halving them until you see not signifficant differences in behavior. Be well...

Fabian.

Date: Sat, 22 Feb 1997
To: k-12sd@sysdyn.mit.edu
From: Fabian Szulanski (FABIANS@IFI.UIB.NO)
Subject: A little more about dt

Dear Fellows,

Another rule of thumb that can be made regarding choosing the correct value for dt: Look at your model's smallest delay, and divide by two if it is a first order delay, or by six if it is a third order delay.This should be a proper value for dt.

Hope this helps.
Best Regards,
Fabian.

Date: Sat, 22 Feb 1997
From: George Richardson (GR383@CNSVAX.ALBANY.EDU)
Subject: Re: dt QUESTION
To: "A.T.S." (CCT18@ROCKWOOD.K12.MO.US)
Cc: k-12sd@sysdyn.mit.edu

The question about "cooktime" and "dt" suggests to me that the focus in the model is far too much on discrete events and not enough on system dynamics. Our simulations aren't great for discrete event stuff -- far better to use a real discrete event simulation language.

Our focus tends to be on the more continuous underlying pressures that underly specific events, without focusing on the events themselves. In this sense, DT is chosen so that it has no discernable impact on the dynamics of the system. It should be chosen large enough so that the simulation does not take forever to run, but small enough so that if one makes it half as big (as a test) one should see no change in the dynamics (some slight change in numbers would be inevitable). In mathematical terms we are simulating "differential" equations, not "difference" equations. It makes a difference in the perspective one takes on the system being modeled.

I'd say reformulate the model so that DT is not a system parameter but simply the simulation time step. Then reformulate the delays using simple stocks and flows. Things should be simpler and more transparent.

...GPR
----------------------------------------------------------------------
George P. Richardson
G.P.Richardson@Albany.edu
Associate professor of public adm., public policy, and info. science
Rockefeller College of Public Affairs and Policy
University at Albany - SUNY, Albany, NY 12222
Phone: 518-442-3859
Fax: 518-442-3398
-----------------------------------------------------------------------

Date: Mon, 24 Feb 1997
To: k-12sd@sysdyn.mit.edu
From: kevinag@MIT.EDU (Kevin Agatstein)
Subject: ROADMAPS Chapter #7 is Complete and Available

Dear SD Community,

The System Dynamics in Education Project, under the directorship of Prof. Jay W. Forrester, has recently completed chapter #7 of Roadmaps, A Guide to Learning System Dynamics. Roadmaps is a self study guide for teachers and students for learning the basic principles of system dynamics. The entire work, including the new chapter seven, is downloadable from:

http://sysdyn.mit.edu/

Chapter seven contains:
- a modeling exercise studying urban growth and stagnation,
- a paper examining dimensional inconsistency,
- a paper by Jay Forrester on System Dynamics, System Thinking, and Soft Operations Management.
- and a paper on Unexpected behavior in Higher Order Positive Feedback Loops.

Please feel free to download any part of RoadMaps. Also, your comments are more than welcome (via email at webmasters@sysdyn.mit.edu).

Thank you.

Best Wishes,
Kevin Agatstein
MIT System Dynamics in Education Project
________________________________________________________________
Kevin Agatstein
Project Manager
System Dynamics in Education Project
MIT Sloan School of Management
| E-Mail: kevinag@mit.edu
Tel: (617) 253-6356 (W)
(617) 494-0371 (H)
Fax: (617) 252-1988

To: k-12sd@sysdyn.mit.edu
From: "A.T.S." (CCT18@ROCKWOOD.K12.MO.US)
Subject: Primary Research Needed
Date: Mon, 24 Feb 1997

I am working on my Masters Project on the topic: How does an interdiscplinary unit emphasizing systems thinking develop critical thinking skills (reasoning)?

I am interested to know if ANY ONE has done qualitative or quantitative research on this topic. I am focusing on how kids are better able to reason through decisions they make about how to change systems, using STELLA modeling software, and using the results of STELLA to support their solutions to systems problems.

I work with 5th grade gifted students. I have not found any research done with elementary kids or middle school kids. I did find some that was done with high school students - and that's a good start.

It needs to be primary research - data collected and analysis of data. If you or know of someone who has conducted this type of research... can you please drop me a line.

AND... Thanks to everyone who responded to my question about DT. Your tips were very helpful!

Art Schneiderheinze
CENTER FOR CREATIVE LEARNING
Rockwood School District
265 Old State Road Ellisville, MO 63021
314 / 394-2597
cct18@mail.rockwood.k12.mo.us

Date: Wed, 26 Feb 1997
From: Guenther Ossimitz (OSSIMITZ@BIGFOOT.COM)
Reply-To: ossimitz@bigfoot.com
Organization: University of Klagenfurt, Austria
To: k-12sd@sysdyn.mit.edu
Subject: Developement of systems thinking skills - empirical research

Hello SD Teachers and Educational Researchers,

My name is Guenther Ossimitz, University of Klagenfurt, Austria/Europe.

For almost ten years I am engaged in the promotion of teaching system dynamics and developing systems thinking skills in the Austrian secondary educational school system. Since 1992 SD is an integrated part of the math-curriculum of natural-science-oriented gymnasiums (grade 11). In the last years I have investigated the developement of systems thinking skills of students aged 14-18 using system dynamics software (POWERSIM).

The design was the following:
1) Instruction of the teachers concerning the basic ideas of systems thinking, system dynamics (SD) and the SD-Software

2) The teachers designed a sequence of lessons (of about 20 hours) about the basic ideas of system dynamics modelling and systems thinking.

3) Before and after the lesson-sequence all students were tested by me about their system thinking skills. (The test was not known to the teachers). Some students were also interviewed about the tests. The design of these (written) tests was the critical issue of the whole investigation. The tested issues of pre-test and post-test should correspond to each other, so that an increase in systems thinking skills could be somehow measured or concluded. The test did not simply check what students had learned in the SD-lessons (it would be rather trivial to define "systems thinking" as that what students learned in the SD-lessons). I tried to give the students a fair chance to express some level of systems thinking skills without having heard anything about SD or SD-modelling and simulation.

One of my main findings was that students without any SD-teaching were able to grasp a rather complex "systemic" issue given as a text. But before being taught about causal loop diagrams and flow diagrams they had serious difficulties to make a pictorial summary of the given situation. After having seen some simple causal loop diagrams students aged 14 and 15 were easily able to denote rather complex situations given as a text.

Another main finding was that the developement of systems thinking skills (according the inidicators I have used) mostly depended upon the teacher. Age, gender, math skills or computer experience had far less influence - the BY FAR most important variable for explaining the increase of systems thinking skills was simply the teacher.

Until now the results of my investigations are only available in German. I am about to summarizethe main results in English within the next weeks. You will find this paper on the web-site mentioned below.

http://www.uni-klu.ac.at/users/gossimit/eng/sdyneng.htm

I have also done extensive theoretical considerations about what systems thinking and systems thinking skills are like, how it can be measured and how it can be developed (especially in the context of "ordinary teaching" at school). I would be very glad to find people in the worldwide SD-community to discuss these issues.

Greetings and best wishes from

================================================
Dr. Guenther Ossimitz
University of Klagenfurt
A-9020 Universitaetsstr. 65
ossimitz@bigfoot.com
http://www.uni-klu.ac.at/users/gossimit/main.htm
JESUS IS LORD - YESTERDAY, TODAY AND FOREVER!

Date: Thu, 27 Feb 97
From: jforestr (Jay W. Forrester)
To: k-12sd@sysdyn.mit.edu (list of participants)
Subject: Infomation
Fcc: k-12

In reading recent messages to this list, I see that several people are asking for information. The long list at the bottom of this message has already been sent to some individually--apologies to them for a repeat.
-------------------------
Note that the address for subscribing, unsubscribing, and administrative matters for the list has been changed to:

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Please do not send messages for the staff at MIT to the K-12sd@sysdyn.mit address because they will go to the entire list.

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We have now installed different software and hope that the problems are solved. If anyone is experiencing trouble, please let us know at the above address.
--------------------------------
You can get a system dynamics bibliography that has over 3000 entries:

Order System dynamics bibliography, specify IBM type PC, or Macintosh

Send $35 in US$ drawn on a US bank to:

System Dynamics Society
49 Bedford Road
Lincoln, MA 01773 USA
Tel: 1-617-259-8259
Fax: 1-617-259-0969
email: SDSociety@aol.com

Three formats are available:
1. For Endnote, a very effective bibliography software available for either Macintosh or PC from:

Niles & Associates, Inc
800 Jones St.
Berkeley, CA 94710 USA
Tel: 510-559-8592
Fax: 510-559-8683
Internet: nilesinc@well.sf.ca.us

I use Endnote and recommend it and use it to search for the references.

2. An exported version with field delimiters that presumably can be loaded into some other kind of database.

3. A simple listing that one can look at in a word processor and do some simple finding operations.

The bibliography can also be downloaded from:
http://www.std.com/vensim/SDBIB.HTM
-----------------------------------------------
The publications list of the System Dynamics Group at MIT is available on the web as an Adobe Acrobat document from:
FTP://Sysdyn.MIT.edu/Ftp/sdep/papers/D-3059-43.pdf
---------------------------------------
Membership in the System Dynamics Society and subscription to the System Dynamics Review are US$80 per year for regular members and US$40 for students. Send application to:

John Wiley & Sons
Periodicals Division, System Dynamics Review
P.O. Box 7247 8491
Philadelphia, PA 19170

or to

John Wiley & Sons
Journals Administration, System Dynamics Review
1 Oldlands Way
Bognor Regis West Sussex PO22 9SA
-------------------------------------
There is a system dynamics discussion group on the Internet. To join, send email to: majordomo@world.std.com In the body of the message, enter the following two lines:

Subscribe system-dynamics
End

More system dynamics information is available at:
http://www.std.com/vensim/sdmailing.html
------------------------------------
The next annual international conference of the System Dynamics Society will be in Istanbul, Turkey in 1997, August 19-22. Write to the System Dyanmics Society,

System Dynamics Society
Milne 300, Rockefeller College
University at Albany, SUNY
Albany, NY 12222
USA
Phone: 518 442-3865

or go to the web page at:
http://ieiris.cc.boun.edu.tr/sd97
----------------------------------------
Many of the major system dynamics books are available from:

PRODUCTIVITY PRESS
541 N.E. 20th Avenue
Portland, OR 97232, USA
tel: 503-235-0600
fax: 503-235-0909
Web page: http://www.ppress.com/
email: staff@ppress.com

Alfeld, Louis Edward, and Alan K. Graham. 1976. Introduction to Urban Dynamics. Portland, OR: Productivity Press. 333 pp.

Forrester, Jay W. 1961. Industrial Dynamics. Portland, OR: Productivity Press. 464 pp.

Forrester, Jay W. 1968. Principles of Systems. (2nd ed.). Portland, OR: Productivity Press. 391 pp.

Forrester, Jay W. 1969. Urban Dynamics. Portland, OR: Productivity Press. 285 pp.

Forrester, Jay W. 1971. World Dynamics. (1973 second ed.). Portland, OR: Productivity Press. 144 pp. Second edition has an added chapter on physical vs. social limits.

Forrester, Jay W. 1975. Collected Papers of Jay W. Forrester. Portland, OR: Productivity Press. 284 pp.

Forrester, Nathan B. 1973. The Life Cycle of Economic Development. Portland, OR: Productivity Press. 194 pp.

Goodman, Michael R. 1974. Study Notes in System Dynamics. Portland, OR: Productivity Press. 388 pp.

Lyneis, James M. 1980. Corporate Planning and Policy Design: A System Dynamics Approach. Portland, OR: Productivity Press. 520 pp.

Mass, Nathaniel J., ed., 1974. Readings in Urban Dynamics: Volume I, Portland, OR: Productivity Press, 303 pp.

Mass, Nathaniel J. 1975. Economic Cycles: An Analysis of Underlying Causes. Portland, OR: Productivity Press. 185 pp.

Meadows, Dennis L. 1970. Dynamics of Commodity Production Cycles. Portland, OR: Productivity Press. 104 pp.

Meadows, Dennis L., et al. 1974. Dynamics of Growth in a Finite World. Portland, OR: Productivity Press. 637 pp.

Meadows, Dennis L., and Donella H. Meadows, ed., 1973. Toward Global Equilibrium: Collected Papers, Portland, OR: Productivity Press, 358 pp.

Morecroft, John D. W., and John D. Sterman, ed., (1994). Modeling for Learning Organizationa, Portland, OR: Productivity Press, 400 pp.

Randers, Jorgen, ed., 1980. Elements of the System Dynamics Method, Portland, OR: Productivity Press, 488 pp.

Richardson, George P., and Alexander L. Pugh III. 1981. Introduction to System Dynamics Modeling with DYNAMO. Portland, OR: Productivity Press. 413 pp.

Roberts, Edward B. 1978. Managerial Applications of System Dynamics. Portland, OR: Productivity Press. 562 pp.

Roberts, Nancy, David Andersen, Ralph Deal, Michael Garet, William Shaffer. 1983. Introduction to Computer Simulation: A System Dynamics Modeling Approach. Portland OR: Productivity Press, 562 pages

Schroeder, Walter W., III, Robert E. Sweeney, and Louis Edward Alfeld, ed., 1975. Readings in Urban Dynamics: Volume 2, Portland, OR: Productivity Press, 305 pp.

----------------------------------
A self-study guide to system dynamics, called "RoadMaps," is available for downloading from:

http://sysdyn.mit.edu

or in paper copy from:
Creative Learning Exchange
Ms. Lees Stuntz, Director
1 Keefe Road
Acton, MA 01720, USA
tel: 1-508-287-0070
fax: 1-508-287-0080
email: stuntzln@tiac.net
---------------------------
For those wanting information on introducing system dynamics in kindergarten through 12th grade education:

1. The Creative Learning Exchange is a nonprofit foundation that acts as a clearinghouse to provide information on system dynamics in precollege education and to help teachers share their experiences. They can be reached at:

Creative Learning Exchange
Ms. Lees Stuntz, Director
1 Keefe Road
Acton, MA 01720, USA
tel: 1-508-287-0070
fax: 1-508-287-0080
email: stuntzln@tiac.net

2. The System Dynamics in Education Project at MIT has a web page with links to pages at other K-12 activities:
http://sysdyn.mit.edu/

3. The FTP site for many of the papers on curriculum is sysdyn.mit.edu

4. An internet discussion group on K-12 issues related to system dynamics is:

k-12all@mit.edu.
Use this above address only for messages that are intended for the entire list.

To subscribe, send email to:
mailmasters@mit.edu.

Please provide the following information:
First Name:
Last Name:
E-mail:
Title:
Organization:
Address:
City:
State or Province:
ZIP or Postal Code:
Country:
Day Phone Number:
Evening Phone Number:
Fax Number:

5. The summer 93 issue of the System Dynamics Review, vol 9 no. 2, was a special issue on "Systems thinking in education" It contains many interesting pieces including reports from the field by teachers.
----------------------------------------------
There are now three good software packages for system dynamics. You can request information:
--------------------------------------------
STELLA for Macintosh or PC:

High Performance Systems
45 Lyme Road, Suite #300
Hanover, NH 03755, USA

Phone: 1-603-643-9636 customer support
tel: 1-800-332-1202 product inquiries
fax: 1-603-643-9502
email: support@hps-inc.com
http://www.hps-inc.com/
--------------------------------------
Powersim for PC:

PowerSim Corporation
12030 Sunrise Valley Drive, Suite 300
Reston, VA 22091, USA

tel: 1-703-391-2779
fax: 1-703-391-2768
email: powersim@powersim.com
http://www.powersim.no/
-------------------------------------------

Vensim for PC or Macintosh:

Ventana Systems, Inc.
149 Waverley Street
Belmont, MA 02178, USA

tel: 1-617-489-5249
fax: 1-617-489-53316
email: vensim@world.std.com
http://news.std.com/vensim/

A "Personal Learning Edition" of Vensim can be downloaded from:
http://news.std.com/vensim/
----------------------------------------------------

Jay W. Forrester
Germeshausen Professor Emeritus and Senior Lecturer
Room E60-389
Massachusetts Institute of Technology
Cambridge, MA 02139, USA
tel: 617-253-1571
fax: 617-252-1998
email: jforestr@mit.edu
Home office tel: 508-369-9372
Home office fax: 508-369-9077