This is part of series of model implemented from "Thinking in Systems" book by Donella Meadows
This is part of series of model implemented from "Thinking in Systems" book by Donella Meadows
Calculating EOQ using classical inventory model
Calculating EOQ using classical inventory model
This model simulates the economics of buying a home. It was created to compare buying a home against using investment returns to pay for rent. According to Micheal Finke, house prices typically run 20x monthly rental rates.      Try cloning this insight, setting the parameter values for real-world s
This model simulates the economics of buying a home. It was created to compare buying a home against using investment returns to pay for rent. According to Micheal Finke, house prices typically run 20x monthly rental rates. 

Try cloning this insight, setting the parameter values for real-world scenarios, and then running sensitivity analysis (see tools) to determine the likely wealth outcomes. Compare buying a home to renting. Note that each run will keep the parameters the same while simulating market volatility.

version 2.0
2 months ago
Like previous models, this model shows the operation of a simple economy, the influence of changes in the consumption rate, and the effect of government intervention. In addition, this model shows changes in the hypothetical general price level. It gives an idea of changes in price trends based on c
Like previous models, this model shows the operation of a simple economy, the influence of changes in the consumption rate, and the effect of government intervention. In addition, this model shows changes in the hypothetical general price level. It gives an idea of changes in price trends based on changes in the quantity of money. NOTE: No general price level exists. Prices provide information for the exchange of individual economic goods.
Circular equations WIP for Runy.    Added several versions of the model. Added a flow to make C increase. Added a factor to be able to change the value 0.5. Older version cloned at  IM-46280
Circular equations WIP for Runy.

Added several versions of the model. Added a flow to make C increase. Added a factor to be able to change the value 0.5. Older version cloned at IM-46280
Solow model without external factors.
Solow model without external factors.
4 10 months ago
ECONOMIC GROWTH feeds on itself, provided the   growth engine   is fed with materials and
finance. In this highly simplified representation  some of the factors that influence economic growth
are show in the incircled green fields. Governments can influence economic growth positively
via investments
ECONOMIC GROWTH feeds on itself, provided the growth engine is fed with materials and finance. In this highly simplified representation  some of the factors that influence economic growth are show in the incircled green fields. Governments can influence economic growth positively via investments  and payouts. The most obvious tool which governments can use to slow an overheated economy is taxation.

Based on a project I am working in [country].  The objective of the Insight is to describe the root causes of the binding constraint of water scarcity on economic growth.      Common Pool Resource Problem  Limits to Growth  Success to Successful   Common Pool Resource is evidenced by uncontrolled (i
Based on a project I am working in [country].  The objective of the Insight is to describe the root causes of the binding constraint of water scarcity on economic growth.

  • Common Pool Resource Problem
  • Limits to Growth
  • Success to Successful
Common Pool Resource is evidenced by uncontrolled (illicit) groundwater abstraction and the declining water tables and water quality.

Groundwater resources are clearly finite (even if the exact limit in uncertain).  As the limit is approached water quantity and quality declines rapidly.  Groundwater is generally being overexploited beyond safe yields.

There is a pattern of success to successful (those with means are better positioned to adapt to increasing scarcity) but this growth in inequality results in social unrest which in turn inhibits reinvestment by the successful.

Green elements are the focus of project investments:  Improved regulatory capacity, infrastructure investments, WUA capacity building, and strengthening cooperatives to support investment in small holders.
Buying and storing electricity when it is cheap, and selling it when it is expensive. What are the benefits, both public and private?
Buying and storing electricity when it is cheap, and selling it when it is expensive. What are the benefits, both public and private?

 Wealth can be seen as the factories,
infrastructure, goods and services the population of a nation dispose of. According
to Tim Garrett,  a scientist who looks at
the economy from the perspective of physics, it is existing wealth that generates
economic activity and growth. This growth demands the

Wealth can be seen as the factories, infrastructure, goods and services the population of a nation dispose of. According to Tim Garrett,  a scientist who looks at the economy from the perspective of physics, it is existing wealth that generates economic activity and growth. This growth demands the use of energy as no activity can take place without its use. He also points out that the use of this energy unavoidably  leads to concentrations of CO2 in the atmosphere.  All this, Tim Garrett says,  follows from the second law of thermodynamics.  If wealth decreases then so does economic activity and growth. The CLD tries to illustrate how wealth, ironically, now generates the conditions and feedback loops  that  may cause it to decline. The consequences are  inevitably economic  stagnation (or secular recession?). 

You can read about the connection Tim Garrett makes between 'Wealth, Economic Growth, Energy and CO2  Emissions' simply by Googling 'Tim Garrett and Economy'.









 Causal loop diagram capturing the interactions, trade-offs, and synergies between agriculture (SDG 2), water availability (SDG 6), economic growth (SDG 8), and life on land (SDG 15). Positive feedback linkages are shown as a positive sign (+), whereas negative feedback linkages are shown wi

Causal loop diagram capturing the interactions, trade-offs, and synergies between agriculture (SDG 2), water availability (SDG 6), economic growth (SDG 8), and life on land (SDG 15). Positive feedback linkages are shown as a positive sign (+), whereas negative feedback linkages are shown with a negative sign (−). The purple arrows indicate the enviro-biophysical linkages. The green arrows indicate the socio-economic linkages. The SDG icons are courtesy of the UN SDG communications material. 


Reference - Bandari, Reihaneh, et al. "Participatory Modeling for Analyzing Interactions Between High‐Priority Sustainable Development Goals to Promote Local Sustainability." Earth's Future 11.12 (2023): e2023EF003948.