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,
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.

Simpler view  IM-70351  combined with Economic View IM-69774  in preparation for integrating with Prevention Investment Framework  (private) IM  Reworked at  Multiscale simpler view IM
Simpler view IM-70351 combined with Economic ViewIM-69774 in preparation for integrating with Prevention Investment Framework (private) IM
This simple model is derived from   D.H. Meadows, Thinking in Systems  chapter 2, figures 27 and 28.  It is designed to explain and demonstrate how the economic system is driven by both an amplifying feedback loop (shown in blue) and a stabilizing feedback loop (shown in red).
This simple model is derived from  D.H. Meadows, Thinking in Systems chapter 2, figures 27 and 28.  It is designed to explain and demonstrate how the economic system is driven by both an amplifying feedback loop (shown in blue) and a stabilizing feedback loop (shown in red).
 Modern industrial civilisation has created massive
interdependencies which define it and without which it could not function. We all
depend on industrial farming to produce the food we eat, we depend on gasoline
being available at the gas station,  on the
availability of electricity and even on the

Modern industrial civilisation has created massive interdependencies which define it and without which it could not function. We all depend on industrial farming to produce the food we eat, we depend on gasoline being available at the gas station,  on the availability of electricity and even on the bread supplied by the local baker. Naturally, we tend to support the institutions that supply the amenities and goods to which we have become accustomed: if we get our food from the local supermarket, it is likely that we would be opposed to it’s closure. This means that the economic system that relies on continuous growth enjoys implicit societal support and that nothing short of environmental disaster or a shortage of essential raw materials will impede it’s growing indefinitely. It is not hard to work out the consequences of this situation!

A model of the ebb and flow of agricultural societies, like China's history. From Khalil Saeed and Oleg Pavlov's WPI 2006  paper  See also the Generic structure  Insight Map
A model of the ebb and flow of agricultural societies, like China's history. From Khalil Saeed and Oleg Pavlov's WPI 2006 paper See also the Generic structure Insight Map
Simple tragedy ​of the commons behavior model.
Simple tragedy ​of the commons behavior model.
This model shows the operation of a simple economy. It demonstrates the effect of changes in the fractional rate of consumption (or the converse the fractional rate of saving.)  In summary, lower rates of consumption (based on production) result in higher rates of production and consumption in the l
This model shows the operation of a simple economy. It demonstrates the effect of changes in the fractional rate of consumption (or the converse the fractional rate of saving.)

In summary, lower rates of consumption (based on production) result in higher rates of production and consumption in the long-run.
 The World3 model is a detailed simulation of human population growth from 1900 into the future. It includes many environmental and demographic factors. THIS MODEL BY GUY LAKEMAN, FROM METRICS OBTAINED USING A MORE COMPREHENSIVE VENSIM SOFTWARE MODEL, SHOWS CURRENT CONDITIONS CREATED BY THE LATEST W

The World3 model is a detailed simulation of human population growth from 1900 into the future. It includes many environmental and demographic factors.

THIS MODEL BY GUY LAKEMAN, FROM METRICS OBTAINED USING A MORE COMPREHENSIVE VENSIM SOFTWARE MODEL, SHOWS CURRENT CONDITIONS CREATED BY THE LATEST WEATHER EXTREMES AND LOSS OF ARABLE LAND BY THE  ALBEDO EFECT MELTING THE POLAR CAPS TOGETHER WITH NORTHERN JETSTREAM SHIFT NORTHWARDS, AND A NECESSITY TO ACT BEFORE THERE IS HUGE SUFFERING.
BY SETTING THE NEW ECOLOGICAL POLICIES TO 2015 WE CAN SEE THAT SOME POPULATIONS CAN BE SAVED BUT CITIES WILL SUFFER MOST. 
CURRENT MARKET SATURATION PLATEAU OF SOLID PRODUCTS AND BEHAVIORAL SINK FACTORS ARE ALSO ADDED

Use the sliders to experiment with the initial amount of non-renewable resources to see how these affect the simulation. Does increasing the amount of non-renewable resources (which could occur through the development of better exploration technologies) improve our future? Also, experiment with the start date of a low birth-rate, environmentally focused policy.

 ​In a recent report, the World Economic Forum
considered that the use of robots in economic activity will cause far more job
losses in the near future than there will be new ones created. Every economic
sector will be affected. The CLD tries to illustrate the dynamic effects of
replacing human work
​In a recent report, the World Economic Forum considered that the use of robots in economic activity will cause far more job losses in the near future than there will be new ones created. Every economic sector will be affected. The CLD tries to illustrate the dynamic effects of replacing human workers with robots. This  dynamic  indicates that if there is no replacement of the  income forgone by the laid off workers, then the economy will soon grind to a halt. To avoid disaster, there must be enough money in circulation, not parked in off-shore investments, to permit the purchase of all the goods and services produced by robots. The challenge for the government is to make sure that this is  case.  

 
 
 A Tragedy of the Commons situation exists whenever two or more activities, each, which in order to produce results, rely on a shared limited resource. Results for these activities continue to develop as long as their use of the limited resource doesn't exceed the resource limit. Once this limit

A Tragedy of the Commons situation exists whenever two or more activities, each, which in order to produce results, rely on a shared limited resource. Results for these activities continue to develop as long as their use of the limited resource doesn't exceed the resource limit. Once this limit is reached the results produced by each activity are limited to the level at which the resource is replenished. As an example, consider multiple departments with an organization using IT resources, until they've exhausted IT capacity.

A sample model for class discussion modeling COVID-19 outbreaks and responses from government with the effect on the local economy.  Govt policy is dependent on reported COVID-19 cases, which in turn depend on testing rates less those who recover       Assumptions   Govt policy reduces infection and
A sample model for class discussion modeling COVID-19 outbreaks and responses from government with the effect on the local economy.  Govt policy is dependent on reported COVID-19 cases, which in turn depend on testing rates less those who recover

Assumptions
Govt policy reduces infection and economic growth in the same way.

Govt policy is trigger when reported COVID-19 case are 10 or less.

A greater number of COVID-19 cases has a negative effect on the economy.  This is due to economic signalling that all is not well.

Interesting insights

Higher testing rates trigger more rapid government intervention, which reduces infectious cases.  The impact on the economy, though, of higher detected cases is negative. 




39 3 months ago
Capitalism is in crisis and climate
change disruption is now beginning to hit the bottom line. Insurance companies
know this well. According to a report by the Bank of England, insured losses
have risen from $10 000 million in 1985 to $50 000 million in 2015. Climate change
cannot be reversed, and e
Capitalism is in crisis and climate change disruption is now beginning to hit the bottom line. Insurance companies know this well. According to a report by the Bank of England, insured losses have risen from $10 000 million in 1985 to $50 000 million in 2015. Climate change cannot be reversed, and extreme weather events  will undoubtedly get worse in the future strengthening the disruptive effects shown in the CLD.  Another dynamic is that companies will continue to automate and, as The Economic Policy Institute has shown, fail to reflect  productivity gains in workers' salaries. The result, stagnating salaries is disastrous for demand, given that capitalism needs endlessly rising demand and consumption. A further serious problem is that as climate change gets worse there will be increasing demands for companies to assume their responsibility and bear the costs of negative externalities.  The CLD shows these factors which are likely to lead to the collapse of the system: when capitalism can no longer generate 'capital' it has stopped to serves any useful purpose. 

 This
paper aims at describing a case where system dynamics modeling was used to evaluate
the effects of information and material supply lead-time variation on sales
contributions margins and operating cash conversion cycle of a commodity export
business.  An empirical dynamic model,
loaded with eco

This paper aims at describing a case where system dynamics modeling was used to evaluate the effects of information and material supply lead-time variation on sales contributions margins and operating cash conversion cycle of a commodity export business.  An empirical dynamic model, loaded with econometric theory of price effect on competitive demand, was used to describe the input data.  The model simulation outputs proved themselves relevant in analyzing the complex interconnections of multiple variables affecting  the profitability in a commercial routine, supporting the decision process among sales managers.

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.
WIP based mostly on Jan
Toporowski  2013 vol 1  and  2018 vol 2  books on Michal Kalecki: An Intellectual Biography   Layout Consistent with  David Wheat MacroEconomic model CLD Insight  by Gene Bellinger  
WIP based mostly on Jan Toporowski 2013 vol 1 and 2018 vol 2 books on Michal Kalecki: An Intellectual Biography  
Layout Consistent with David Wheat MacroEconomic model CLD Insight by Gene Bellinger  
The model is built to demonstrates how Burnie Tasmania can deal with a new COVID-19 outbreaks, taking government policies and economic effects into account. The susceptible people are the local Burnie residents. If residents were infected, they would either recovered or dead. However, even they do r
The model is built to demonstrates how Burnie Tasmania can deal with a new COVID-19 outbreaks, taking government policies and economic effects into account.
The susceptible people are the local Burnie residents. If residents were infected, they would either recovered or dead. However, even they do recover, there is a chance that they will get infected again if immunity loss occurs.
From the simulation result we can see that with the implementation of local government policies including travel ban and social distancing,  the number of infected people will decrease. The number of recovered people will increase in the first 5 weeks but then experience a decrease.
In addition, with the implementation of local government policy, the economic environment in Burnie will be relatively stable when the number of COVID-19 cases is stable.
Overview of Part F Ch 25 and 26 of Mitchell Wray and Watts Textbook see  IM-164967  for book overview
Overview of Part F Ch 25 and 26 of Mitchell Wray and Watts Textbook see IM-164967 for book overview
 Economic growth cannot go on forever, although politicians and most economist
seem to think so. The activity involved in economic growth necessarily  generates entropy (disorder and environmental degradation). Entorpy in turn generates powerful negative feedback loops which will, as
a response from

Economic growth cannot go on forever, although politicians and most economist seem to think so. The activity involved in economic growth necessarily  generates entropy (disorder and environmental degradation). Entorpy in turn generates powerful negative feedback loops which will, as a response from nature, ensure that economic activity will eventually grind to a complete halt.  In these circumstances organised society cannot persist and will collapse. The negative feedback loops shown in this graph have already started to operate. The longer economic growth continues unabated, the more powerful these negative feedback loops will become. How long can economic growth continue before it is overwhelmed? It may not be very far in the future.

Summary of Ch 27 of Mitchell Wray and Watts Textbook see  IM-164967  for book overview See  IM-169093  for added dynamic evolutionary economics history
Summary of Ch 27 of Mitchell Wray and Watts Textbook see IM-164967 for book overview See IM-169093 for added dynamic evolutionary economics history