This model shows the structure and operation of a simple economy. It can represent economic systems at different levels of abstraction (e.g. a single good, a group of goods, multiple groups, & an "economy.")  In summary, lower rates of consumption (based on production) result in higher rates of
This model shows the structure and operation of a simple economy. It can represent economic systems at different levels of abstraction (e.g. a single good, a group of goods, multiple groups, & an "economy.")

In summary, lower rates of consumption (based on production) result in higher rates of production and consumption in the long-run. Rates of consumption over 100% of production will diminish the savings stock and eventually cause rates of production and consumption to fall.
From Walrave ISDC2014  paper  Counteracting the success trap in publically owned corporations
From Walrave ISDC2014 paper Counteracting the success trap in publically owned corporations
A government deficit means that more money has been transferred in the form of payments or investments from the government sector to the private sector than the government has received in taxes. As shown in the drawing,  GOVERNMENT DEFICIT = INCOME AND SAVING for the private sector. Not all the inco
A government deficit means that more money has been transferred in the form of payments or investments from the government sector to the private sector than the government has received in taxes. As shown in the drawing,  GOVERNMENT DEFICIT = INCOME AND SAVING for the private sector. Not all the income transferred from the government to the private sector will be employed and some of it will be saved in bank accounts. It is therefore correct to say that Government Deficits lead to Private Sector Saving. It is equally true to say that Investment  leads to Saving. This is important because in the current recession one of the major problems is the massive amount of private debt. In these circumstances a cumulative government deficit is necessary to help the private sector save and repay some of its debt. Note: I have not taken into account the foreign sector here which can also contribute to private sector income and saving.
  Goodwin Model:   This is a basic version of the Goodwin Model based on Kaoru Yamagushi (2013),  Money and Macroeconomic Dynamics , Chapter 4.5 ( link )     Equilibrium conditions:   Labor Supply  = 100  Devation from the equilibrium conditions generates growth cycles.
Goodwin Model:
This is a basic version of the Goodwin Model based on Kaoru Yamagushi (2013), Money and Macroeconomic Dynamics, Chapter 4.5 (link)

Equilibrium conditions:
  • Labor Supply = 100
Devation from the equilibrium conditions generates growth cycles.
This model analyzes the interaction between climate change mitigation and adaptation in the land use sector using the concept of forest transition as a framework.
This model analyzes the interaction between climate change mitigation and adaptation in the land use sector using the concept of forest transition as a framework.
WIP Summary of MIchael Hudson's  Book  Killing the Host: How Financial Parasites and Debt destroy the Global Economy 
WIP Summary of MIchael Hudson's Book Killing the Host: How Financial Parasites and Debt destroy the Global Economy 
Adapted from Hartmut Bossel's "System Zoo 3 Simulation Models, Economy, Society, Development."  ​Population model where the population is summarized in four age groups (children, parents, older people, old people). Used as a base population model for dealing with issues such as employment, care for
Adapted from Hartmut Bossel's "System Zoo 3 Simulation Models, Economy, Society, Development."

​Population model where the population is summarized in four age groups (children, parents, older people, old people). Used as a base population model for dealing with issues such as employment, care for the elderly, pensions dynamics, etc.
Very simple causal loop diagram of a loan, which can be any loan. However, when the loan is a fixed amount, that needs to be repaid in x periods, you can cross out the 'taking out' arrow from debt to bank account.
Very simple causal loop diagram of a loan, which can be any loan. However, when the loan is a fixed amount, that needs to be repaid in x periods, you can cross out the 'taking out' arrow from debt to bank account.
This is a toy model of an investment market.    Households follow a simple ratio to invest in bonds or equities.  In part, the investment decision is stochastic, such that stock market returns are volatile, with equities more volatile than bonds and with a higher yield. As such, the system shows inc
This is a toy model of an investment market.

Households follow a simple ratio to invest in bonds or equities.  In part, the investment decision is stochastic, such that stock market returns are volatile, with equities more volatile than bonds and with a higher yield. As such, the system shows increasing volatility as the investment bubble grows.


Stock-flow diagram of compound interest with table and graph output in interest and savings development per year in Dutch. With the possibility of a negative interest from a predefined threshold.
Stock-flow diagram of compound interest with table and graph output in interest and savings development per year in Dutch. With the possibility of a negative interest from a predefined threshold.
Very basic stock-flow diagram of simple interest with table and graph output in interest, bank account and savings development per year. Initial deposit, interest rate, yearly deposit and withdrawal, and initial balance bank account can all be modified.  I have developed a lesson plan in which stude
Very basic stock-flow diagram of simple interest with table and graph output in interest, bank account and savings development per year. Initial deposit, interest rate, yearly deposit and withdrawal, and initial balance bank account can all be modified. 
I have developed a lesson plan in which students work on both simple and compound interest across both IM and Excel. I also wrote an article about this in Dutch, which you can translate using for example Google Translate: https://docs.google.com/document/d/1SsyJF89jT8xwAmtDaMS0rfdUefW7pPwBnw4ASauVeFw/edit?usp=sharing
10 months ago
 MODERN MONETARY THEORY SHOWS HOW FULL EMPLOYMENT CAN BE ACHIEVED!  POTENTIAL GDP is a level of overall spending - by the government and the non-government sector - at which there is full employment. If the economy is not operating at
its potential, then the  private sector
has failed to invested or

MODERN MONETARY THEORY SHOWS HOW FULL EMPLOYMENT CAN BE ACHIEVED!

POTENTIAL GDP is a level of overall spending - by the government and the non-government sector - at which there is full employment. If the economy is not operating at its potential, then the  private sector has failed to invested or spend enough to generate the necessary growth nor has income  from net exports contributed enough. This only leaves the government to close the spending gap. Conceptually, a government disposing of its own freely floating currency could act using two powerful tools -  spending in excess of tax revenue, and taxation - to ensure that the gap between the actual economic activity and potential GDP is quickly closed. Achieving the  full employment that prevailed for 30 years between 1945 and 1975 in western economies is definitely possible! 

This model shows the structure and operation of a simple economy. It can represent economic systems at different levels of abstraction (e.g. a single good, a group of goods, multiple groups, & an "economy.")  This model has one significant difference from Model 4. The  fractional consumption rat
This model shows the structure and operation of a simple economy. It can represent economic systems at different levels of abstraction (e.g. a single good, a group of goods, multiple groups, & an "economy.")

This model has one significant difference from Model 4. The fractional consumption rate table serves the purpose of demonstrating the effects of changes in the fractional consumption rate (or the converse the fractional rate of saving) from 100% to less-than 100% to more-than 100%.

It demonstrates dramatically the effects of significant changes in consumption rates.
Clone of Pesticide Use in Central America for Lab work        This model is an attempt to simulate what is commonly referred to as the “pesticide treadmill” in agriculture and how it played out in the cotton industry in Central America after the Second World War until around the 1990s.     The cotto
Clone of Pesticide Use in Central America for Lab work


This model is an attempt to simulate what is commonly referred to as the “pesticide treadmill” in agriculture and how it played out in the cotton industry in Central America after the Second World War until around the 1990s.

The cotton industry expanded dramatically in Central America after WW2, increasing from 20,000 hectares to 463,000 in the late 1970s. This expansion was accompanied by a huge increase in industrial pesticide application which would eventually become the downfall of the industry.

The primary pest for cotton production, bol weevil, became increasingly resistant to chemical pesticides as they were applied each year. The application of pesticides also caused new pests to appear, such as leafworms, cotton aphids and whitefly, which in turn further fuelled increased application of pesticides. 

The treadmill resulted in massive increases in pesticide applications: in the early years they were only applied a few times per season, but this application rose to up to 40 applications per season by the 1970s; accounting for over 50% of the costs of production in some regions. 

The skyrocketing costs associated with increasing pesticide use were one of the key factors that led to the dramatic decline of the cotton industry in Central America: decreasing from its peak in the 1970s to less than 100,000 hectares in the 1990s. “In its wake, economic ruin and environmental devastation were left” as once thriving towns became ghost towns, and once fertile soils were wasted, eroded and abandoned (Lappe, 1998). 

Sources: Douglas L. Murray (1994), Cultivating Crisis: The Human Cost of Pesticides in Latin America, pp35-41; Francis Moore Lappe et al (1998), World Hunger: 12 Myths, 2nd Edition, pp54-55.

 Goodwin cycle  IM-2010  with debt and taxes added, modified from Steve Keen's illustration of Hyman Minsky's Financial Instability Hypothesis "stability begets instability". This can be extended by adding the Ponzi effect of borrowing for speculative investment.

Goodwin cycle IM-2010 with debt and taxes added, modified from Steve Keen's illustration of Hyman Minsky's Financial Instability Hypothesis "stability begets instability". This can be extended by adding the Ponzi effect of borrowing for speculative investment.

Investigations into the relationships responsible for the success and failure of nations. This investigation was prompted after reading numerous references on the subject and perceiving that *Why Nations Fail: The Origins of Power, Prosperity, and Poverty* by Acemoglu and Robinson seem to make a gre
Investigations into the relationships responsible for the success and failure of nations. This investigation was prompted after reading numerous references on the subject and perceiving that *Why Nations Fail: The Origins of Power, Prosperity, and Poverty* by Acemoglu and Robinson seem to make a great deal of sense.

Original model done for The Perspectives Project though recast into Kumu.
WIP based on Bill mitchell's blogs.  Sectoral balances are relationships among money flows during an accounting period. Where we perceive accumulations of past imbalances to be accrued is another matter....
WIP based on Bill mitchell's blogs. 
Sectoral balances are relationships among money flows during an accounting period. Where we perceive accumulations of past imbalances to be accrued is another matter....