Featured Author

John Hayward

I am a Visiting Research Fellow in Mathematics at the University of South Wales. Before my retirement, I was a senior lecturer at the university, teaching specialist courses in system dynamics, mathematical modelling and agent-based methods. I was awarded a BSc in astrophysics, and a PhD in applied mathematics, from the University of London, and then spent my career as a lecturer in mathematics. My research is in mathematical sociology with applications to the spread of social phenomena, such as ... Read more

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We found 40 items
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#1

Feebate model

by Allyson Beall
This simulation offers users the opportunity to explore the impact of fees on conventional vehicle a ... Read more
This simulation offers users the opportunity to explore the impact of fees on conventional vehicle and rebates on lower to no emission vehicles.
sim ⋮ 8,592 runs
Environment Technology Science Economics Education
11346.577
#2

Housing Supply and Demand

by isee systems
Use this learning lab to investigate the housing crisis. Play with interest rates as if you are Chai ... Read more
Use this learning lab to investigate the housing crisis. Play with interest rates as if you are Chairman of the Federal Reserve and see the impact on housing supply and demand. What happens when banks relax mortgage requirements and more people qualify to buy homes?
sim ⋮ 5,549 runs, 891 downloads
Download Model
Modules finance debt economics housing demand
10973.033
#3

FermOpt: the fermentation optimisation game

by Conan Fee
A semi-batch fermenter simulation, in which players must explore the effects of various operating pa ... Read more
A semi-batch fermenter simulation, in which players must explore the effects of various operating parameters to try to maximise the production of an imaginary product, "WonderMab", for the lowest possible cost.
sim ⋮ 3,828 runs
Biology Science Education fermenter fermentor
9822.613
#4

Greenhouse Gas Emissions Management Tool

by SMI-JKMRC
sim ⋮ 2,316 runs
Environment Business Technology Science Economics
6402.75
#5

PEOPLE-EXPRESS

by Khalid+Saeed
A SIMPLIFIED VERSION OF PEOPLE EXPRESS GAME FOR CLASSROOM OR GROUP USE
sim ⋮ 14,467 runs
Business Economics Education
5424.2334
#6

Financial instability

by Crelis
Market-capitalism typically goes through cycles of expansion and contraction. Every now and then, th ... Read more
Market-capitalism typically goes through cycles of expansion and contraction. Every now and then, these common economic cycles go off the hinges. They become unstable and can lead to recessions, crises and depressions—phenomena that economists typically look to exogenous forces to explain. Alternative, mostly Marxian and Keynesian, explanations for the instabilities have been sought within the structure of the economic system itself. One such explanation is provided by Steve Keen in his Goodwin-Minsky model. The model effectively mimics the dynamics of key indicators prior to, during and after the 2007/08 crisis. However, the model is also over-specified, highly sensitive to initial conditions and therefore more difficult to convey. In line with George Box’s plea for parsimony, this paper presents a more straightforward version of Keen’s model that remains consistent with its fundamental behaviour. The model also illustrates the potential for further dialogue between Marxian economics and system dynamics.
model ⋮ 1,861 downloads
Download Model
Financial instability Karl Marx Richard Goodwin Hyman Minsky Steve Keen
5213.58
#7

Increasing Public Transport Usage in Bergen by Expanding Bus Route Availability

by UiB MINDS
© Will Noyes 2021 This model is intended to teach and demonstrate various concepts related to buildi ... Read more
© Will Noyes 2021 This model is intended to teach and demonstrate various concepts related to building policy models. This model specifically seeks a policy to increase bus ridership in Bergen through expanding bus route availability. The policy takes into account a dynamic goal that factors in population growth and includes financial impact analysis to demonstrate how to incorporate financial and budgetary considerations into a policy proposal.
model ⋮ 1,556 downloads
Download Model
Economics Education finance budget accounting
4281.137
#8

SetMP

by David Wheat
sim ⋮ 16,141 runs
Economics
4180.42
#9

COVID-19 Economy

by isee systems
This models the economic impacts of an extended shutdown due to the coronavirus pandemic and explore ... Read more
This models the economic impacts of an extended shutdown due to the coronavirus pandemic and explore the policies adopted by the United States to mitigate these effects.
model ⋮ 2,946 downloads
Download Model
Business Science Economics COVID-19 coronavirus
3059.884
#10

COVID-19 Economy Model

by isee systems
Our latest Story of the Month explores the economic cost of the COVID-19 stay-at-home orders in the ... Read more
Our latest Story of the Month explores the economic cost of the COVID-19 stay-at-home orders in the United States. Are there policies that can help mitigate these costs? Do the provisions of the CARES Act have a significant effect on the economic outcomes? Find out in our new simulation.
sim ⋮ 2,487 runs
Business Economics Education COVID-19 coronavirus
2942.7473
#11

Preventing CVD deaths in Australia

by Sax Institute
This simulation has been produced by the Sax Institute and funded by Amgen Australia in 2019. It for ... Read more
This simulation has been produced by the Sax Institute and funded by Amgen Australia in 2019. It forecasts and compares different strategies to prevent health and economic burden from cardiovascular disease. 
sim ⋮ 2,330 runs
Biology Science Economics Education Health
2291.0413
#12

M330C6.2.4 Resource tax

by SDG Bergen
sim ⋮ 3,633 runs
Biology Economics Ecology Education
1906.05
#13

Carbon Budget Simulator

by Peter Victor
This model determines the number of years in which the global carbon budget will be exhausted. You s ... Read more
This model determines the number of years in which the global carbon budget will be exhausted. You set the carbon budget as a multiple of current carbon dioxide emissions. You choose a rate of economic growth and a rate of reduction in emissions intensity (emissions/GDP). The model puases when the carbon budget is exhausted. The model can be used to determine the exhaustion of national and regional carbon budgets as well following the same steps.
sim ⋮ 1,395 runs
Environment Technology Science Economics
1695.125
#14

Energy Equilibrium Model

by Girts Bohvalovs
To compensate the variability and non-controllability of seasonally generated renewable energy (RES) ... Read more
To compensate the variability and non-controllability of seasonally generated renewable energy (RES) (daily fluctuations in solar radiation intensity, wind speed, etc.) development of sufficient energy storage infrastructure in the regions will play a major role in transforming RES supply potential into reality. However, local public authorities that are responsible for creating an enabling policy environment for RES infrastructure development in regions encounter numerous challenges and uncertainties in deploying sufficient energy accumulation that often remain unanswered due to a lack of knowledge and on-site capacity, which in turn significantly hinders the regional path to climate neutrality. This project aims to develop an Energy Equilibrium Platform – an interactive and easily applicable tool to support municipalities and energy suppliers in decision-making related to the development of efficient action plans to accelerate local RES utilization in the region. Energy Equilibrium Platform will help municipalities to:(1) Identify the most optimal RES storage development strategy and its impact on energy flexibility in the region; (2) Help to determine the key factors affecting energy equilibrium (balance between the produced and the consumed energy) in the region; (3)Help to develop policy mechanisms and action plans to enhance local RES in the region; (4)Help to anticipate risks and avoid making expensive mistakes (e.g. investing in inappropriate technological solutions).
sim ⋮ 660 runs
Technology Economics Education
1325.69
#15

tragedy of commons water crisis

by Eleanor+Hagan
Water scarcity is the lack of fresh water resources to meet water demand.
model ⋮ 800 downloads
Download Model
Environment Biology Business Technology Science
1210.05
#16

Fish Banks, Ltd.Game

by Saeed Langarudi
In the Fish Banks, Ltd. game (originally developed as a board game by Professor Dennis L. Meadows in ... Read more
In the Fish Banks, Ltd. game (originally developed as a board game by Professor Dennis L. Meadows in 1986), teams of players manage their own fishing companies. At the beginning of the game, each fishing company has equal financial resources and fishing fleet. Each company has the same operating costs and technology. At the beginning of every simulated year, the companies make decisions about building, buying, and/or selling ships, whether to fish or not, and how far to send their fleet for fishing. The game's objective is to maximize total assets at the end of the simulation. The game developed here is a modified version of the Meadows' game as explained in the game rules.
sim ⋮ 353 runs
Environment Economics Ecology Education Dennis Meadows
1118.8804
#17

Microchips and the Auto Industry

by isee systems
After 2 years unreliable supply chain of microchips, the auto industry is struggling to adopt.
sim ⋮ 1,606 runs, 115 downloads
Download Model
Business Economics Education
1030.024
#18

ccf poverty popuplation and climate change

by ROHIT+SOLANKI
a cld covering various sectors and majorly interacting between social and ecological systems.
diagram ⋮ 679 downloads
Download Model
Environment Biology Business Technology Science
1015.127
#19

Positive Feedback

by Franco Posa
Basic positive feedback model
model ⋮ 673 downloads
Download Model
Environment Biology Business Technology Science
989.897
#20

The Shrimp Lab

by Bob Landel
“The Shrimp Commodity System Learning Lab” was designed for individuals seeking to build their syste ... Read more
“The Shrimp Commodity System Learning Lab” was designed for individuals seeking to build their systems thinking muscle and policy-design skills. It has been used successfully in undergraduate and graduate courses where business sustainability and/or system dynamics applications are emphasized. The format offers learners a progression of interactive experiences on which to build an understanding of the issues of the global shrimp industry system, including wild fisheries and aquaculture, its financial instability, the environmental issues it faces, and how individual policy alternatives can be tested, analyzed and combined to address industry performance. The Learning Lab has two learning pathways: The Systems Thinking Basics course shows the application of systems thinking and stock-flow mapping as tools to hypothesize and express underlying system feedback structures contributing to issues such as resource depletion and environmental pollution. The Policy and Scenarios Advanced course deepens understanding of systems behavioral patterns by presenting policies which address commodity systems behavior challenges and by using alternative scenarios dealing with market forces as tests. Students in a course could be asked to provide their recommendations for a policy set which best achieves multiple performance objectives: industry wide profit growth for the two industry sectors, achieve coastal effluents improvements, and avoid large oscillations of shrimp populations and resource depletion in the wild fishery. Additional information is available in the Technical Note (UVA-OM-1428) that offers information for individual preparation assignments, suggestions for Group workshop activities, helpful causality notes for instructors, and insights into policy analyses. To obtain this Note or request further information about related shrimp industry cases, (UVA OM 1388 and 1389), contact Darden Business Publishing at http://store.darden.virginia.edu/contactus The Learning Lab was developed by Chris Soderquist, Pontifex Consulting and Professor Robert D. Landel of the Darden School, University of Virginia and is based on original research from Donella Meadows Institute (formerly Sustainability Institute) and Pontifex Consulting. Copyright © 2009 by the University of Virginia Darden School Foundation, Charlottesville, VA.
sim ⋮ 6,469 runs
Environment Biology Business Economics Ecology
945.7813
#21

plugrisost

by elaheh roohbakhsh
RWH system
model ⋮ 551 downloads
Download Model
Environment Technology Economics Ecology Education
903.93665
#22

Production function game

by Martin Schaffernicht
You manage a toy production plant in a competitive marked (where you are a price-taker). Your goal i ... Read more
You manage a toy production plant in a competitive marked (where you are a price-taker). Your goal is to adjust production to a quantity that will yield the maximal profit, calculated by the total revenue - total costs. You have to adjust two factors: labor hours and machine hours. These factors cause costs, and they drive production (as represented by a Cobb-Douglas production function).
sim ⋮ 322 runs
Business Economics Education Schaffernicht Universidad de Talca
899.85
#23

Tanzania Dairy Investment Model

by Charles Nicholson
This is a model that allows assessment of investments in Tanzania's dairy sector from 2024 to 2030
sim ⋮ 1,318 runs
Business Technology Economics
805.72266
#24

Negative Feedback

by Franco Posa
Basic negative feedback model
model ⋮ 533 downloads
Download Model
Environment Biology Business Technology Science
788.437
#25

WCCI Supply Chain Assessment Model

by Charles Nicholson
Assesses supply chain management decisions for a cheese converting company
sim ⋮ 2,002 runs
Business Economics
779.5993
#26

Electric vehicles sales in Norway

by Daria Yermolova
This model was copied from MINDSproject: Daria Yermolova and Valentina Orliuk examine the various e ... Read more
This model was copied from MINDSproject: Daria Yermolova and Valentina Orliuk examine the various effectors on the electric car market in Norway as part of a joint project for SD304 at UIB.
model ⋮ 516 downloads
Download Model
Environment Business Technology Science Economics
777.7
#27

MLL24

by David Wheat
sim ⋮ 2,302 runs
Economics Education
774.0233
#28

trag of commons

by Eleanor+Hagan
diagram ⋮ 554 downloads
Download Model
Environment Biology Business Technology Science
772.94
#29

6 - Nuclear Fuel Depletion and Burn-up

by INPRO
Nuclear fuel depletion and burnup simulator is the ease-to-use isotopic and burnup simulator which c ... Read more
Nuclear fuel depletion and burnup simulator is the ease-to-use isotopic and burnup simulator which can enable nuclear planning experts to assist nuclear energy system modelling and scenario analysis studies as part of material flow and economics analyses.
sim ⋮ 903 runs
Technology Science Education Nuclear
761.645
#30

Market Growth

by Insta Innovación, S.C.
Marketing is not an activity limited to one corporate subdivision. Marketing interacts with research ... Read more
Marketing is not an activity limited to one corporate subdivision. Marketing interacts with research to guide product design. Marketing interacts with price policy to determine profitability. Marketing interacts with production to determine product availability and quality. Marketing interacts with personnel policy and training to deter- mine skill in the marketing activities. Marketing interacts with the corporate informa- tion system in determining how market information guides resource allocation within the company. The relationship of marketing policy to the market, to the other corporate functions, and to competition is particularly intimate. There are many interacting feed- back loops. These loops are capable of producing product growth or stagnation and decline. How the loops are balanced determines product profitability.
sim ⋮ 362 runs
Business Economics Education Market growth marrketing
759.942
#31

M330C1.2.9b

by SDG Bergen
Simulation of nonrewnewable resource with economics
sim ⋮ 3,419 runs
Education
742.65
#32

Räuber Beziehung

by gringe
harry is gringe und er liebt hermine doch! Harry Styles wurde am 1 februar 26!!!!! Ich liebe Pomme ... Read more
harry is gringe und er liebt hermine doch! Harry Styles wurde am 1 februar 26!!!!! Ich liebe Pommes mit Mayo und Gurken Nano wurde von aliens geschickt
model ⋮ 395 downloads
Download Model
Environment Biology Business Technology Science
738.9817
#33

Market acquisition-multiplayer

by Robinson Salazar Rua
This is a multi-player game with storytelling, which describes the basic feedbackloops related to ma ... Read more
This is a multi-player game with storytelling, which describes the basic feedbackloops related to market acquisition. The model starts in dynamic equilibrium, and the goal is to maximize market share and accumulated profits. To this end, users have decision power on marketing investments, product price, and product lifespan.
sim ⋮ 339 runs, 20 downloads
Download Model
Business Economics Education Multiplayer Bass difussion
680.46735
#34

mobile-MaDE-IT

by Joshua Aboah
A mobile version of the Marek's Disease Impact and Trade-off (MaDE-IT) simulator.
sim ⋮ 1,600 runs
Economics livestock
671.12665
#35

M330C6.2.5 ITQ policy

by SDG Bergen
sim ⋮ 1,674 runs
Economics Ecology Education
646.76
#36

Platform Startup Flight Simulator

by Edward Anderson
This flight simulator allows the user to make different investments in a startup platform's function ... Read more
This flight simulator allows the user to make different investments in a startup platform's functionality. The platform has two "sides," one is customers, the other, suppliers. The Platfrom can also monetize by setting a subscription fee on the customer or supplier sides or both.
sim ⋮ 656 runs
Business Technology Economics Platforms
646.66
#37

test

by Kenneth Keatts
Test
model ⋮ 435 downloads
Download Model
Environment Biology Business Technology Science
635.29
#38

iSDG China

by Millennium Institute
sim ⋮ 944 runs
Environment Economics SDG development
630.24
#39

lunar resources

by Marc-Andre
model ⋮ 768 downloads
Download Model
Environment Business Technology Economics
616.48
#40

SIPOS-VOICE

by Beni Okarda
sim ⋮ 1,593 runs
Environment Economics
587.49664
X

Uploading a Bundle from Zip

Instead of creating bundles, categories, and assemblies one by one, you can upload a single zip file that contains all of your bundle's content. To create your zipped bundle, make a folder with your bundle's name and add subfolders with your categories' names. The folder tree should have the same structure that you want the categories to have in your bundle. Place your assembly .stmx files in the appropriate category folders, then zip your bundle folder and upload it using the Upload Bundle from Zip link above.

Assemblies, Bundles, and Categories

Assemblies are self contained models that demonstrate common ways to connect together building blocks and that can be used as parts of other models. This is analogous to using prefabricated wall and roof pieces to construct a house.

Bundles are groups of assemblies with a common use or theme. For example, a Health Care bundle might contain a variety of assemblies that aid in creating health care models. When you download assemblies from the isee Exchange™, you download an entire bundle, rather than individual assemblies.

Categories are subgroups of assemblies within a bundle. For example, a Health Care bundle might contain a Funding category for assemblies related to the management of hospital funds. All assemblies must be assigned to a category—they cannot be assigned to the root of a bundle.

Assemblies, bundles, and categories can be created and uploaded to the isee Exchange™ via the options on the Manage My Assemblies page. To learn more, visit our help pages, or take our assemblies tutorial.

Sim App (Sim)

An interface that allows users to interact with a model.

Image of a sim

Sim apps allow users to interact with a model using buttons, sliders, knobs, tables, graphs, and storytelling. These interactions help users understand how parts of a system interact.

Interfaces are created by model authors in the Stella desktop software and can be uploaded to the isee Exchange™.

Model

A diagram that represents how elements in a system influence one another.

Image of a model

Models are mathematical representations of how elements in a system are connected and interact (e.g., ecosystems, organizations, supply chains). When running models on the isee Exchange™, results can be viewed in output devices like graphs and tables.

Models appear in the isee Exchange™ directory when authors upload them from the Stella® desktop software or create them with Stella Online™.

Causal Loop Diagram (CLD)

A map that represents the feedback structure of a system.

Image of a CLD

CLDs are high-level maps that represents the feedback structure of a system and easily communicate the essence of a model. They appear in the isee Exchange™ when authors upload them from the Stella desktop software or create them with Stella Online™.