Archive for May, 2009

Storytelling Simulations

May 21st, 2009 No comments

Storytelling is a powerful feature that provides precise control over the presentation of a model to your audience. It also allows kiosk-style presentations to be created that step through the model, explaining it piece-by-piece. Many people use it only for this purpose, but storytelling offers so much more.

Because a basic premise of System Dynamics is that structure and behavior are linked, one of the key ideas behind storytelling is to allow the behavioral story to grow as the structural story unfurls. To create this effect, we neutralize structure that is not showing. This is extremely powerful because it allows you, for example, to selectively show the behavior of different loops within the system.

A simple example will solidify this concept. Consider the following simple population model:


The death rate multiplier is a simple resource constraint on the growth of population. More complex constraints would also affect the birth rate.

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Insight-based Model Investigates the Housing Crisis

May 5th, 2009 3 comments

wpi-logoFor the past few months I’ve been taking a distance learning course at WPI called “System Dynamics Foundations: Managing Complexity”. The course covers a broad range of topics about the system dynamics methodology and how it has been applied in the real world.

One of the things I really like about the course is the different perspective the instructors bring to the table (or in this case my computer screen.) Last week’s lecture focused on three different styles of system dynamics modeling – Causal Loop Diagrams (CLDs), insight-based models and calibrated models.  While both instructors agreed there is value in all three approaches to dynamic modeling, there was clearly a difference of opinion about what is required to actually DO something with a proposed solution to a problem.

The topic got me to thinking about the types of STELLA and iThink models that are being built and how they are being used to DO something about real world problems. I would guess that the majority of the models fall into the insight-based category.   One of the reasons we put so much effort into creating communication features in our software is so that those insights can be shared and discovered by others.  The “ah-ha” moments that come from experimenting with simulations are often a great vehicle for getting conversations going about a particular issue and discussing possible solutions.

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Cleaner Vehicles through Fees & Rebates

May 4th, 2009 1 comment


Imagine you have been asked to design an incentive program to promote the sale of cleaner vehicles in your city. You are convinced that purchase price incentives are the key to shifting consumer choices. You believe a large rebate could encourage the purchase of electric cars and other alternative-fueled vehicles.

This is the background story for an online simulation that allows students to experiment with applying fees and rebates to automotive sales to help reduce air pollution.

As the player, your job is to manage a “feebate” program for the city that will help reduce vehicle pollution.  The program offers large rebates on purchases of cleaner vehicles, (electric vehicles, hybrid-electric vehicles and vehicles fueled with compressed natural gas) and imposes fees on vehicles that have high pollution rates.

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Lake Morey – A Great Place for a Summer Workshop!

May 1st, 2009 No comments

View from Lake Morey Resort glof course

Our next Introduction to Dynamic Modeling Workshop is scheduled to be at Lake Morey Resort in Fairlee, Vermont on August 5th – 7th.  You may be wondering  “Why Lake Morey?”

For starters, the resort is located along the shores of Lake Morey, surrounded by Vermont hills in a beautiful natural setting. It has a golf course, tennis courts and lake front swimming facilities that attendees can enjoy while taking a break from the workshop.

Not only is Vermont a wonderful place to visit in the summer months, but Lake Morey is only ten miles north of the isee systems offices. We love being able to drop in on workshops that are close by or meet with customers over a beer after hours.  It gives us an opportunity to learn more about the amazing work people are doing with our software and to get their ideas for future development.  It also gives our customers a chance to get to know us and to put a face to someone they’ve been talking to over the phone or via email.

We hope to see you this summer! If there’s someone on the isee staff that you’d like to meet with, be sure to let us know.

Please give us a call at (603) 448-4990 or send an email to to check on availability.