This simple model describes wealth accumulation. The value in income is described by the following simple equation:

This model shows the operation of a simple economy with two modifications made to Model 2 -- 1) feedback from production rate to consumption rate and 2) the use of a fractional rate input for calculating consumption rate. 

In summary, lower fractional rates of consumption (based on production) result in higher levels of Savings.

First pass at model depicting importance of Net Capital Accumulation on economic growth of firm - from firm's perspective

Based on chapter 14 of Modeling Dynamic Economic Systems

Ocean/atmosphere/biosphere model tuned for interactive economics-based simulations from Y2k on.

On the occasion of th G20-meeting in Toronto, the German Economics minister Herr Schaüble said that without restoring confidence it would not be possible to get consumer spending and business investment going. Similar remarks were made by David Cameron and Señor Zapatero of Spain. All maintain that confidence is a pre-requisite to get growth going and that, therefore, it was imperative to reduce fiscal deficits. Reducing the fiscal deficit will restore confidence at first. However, reducing the deficit very quickly will introduce a dynamic that may cause the economy to decline - and perhaps depress  consumers demand even further.  It will actually destroy confidence: few businesses are inclined to invest in a shrinking economy. Cutting the deficit too rapidly or too steeply can lead to a confidence trap.

NOTE: A big experiment is now taking place in the UK - the government has cut public spending severely! Will this lead to hardship and, perhaps, social unrest? 

Nobody seems to notice bubbles until they burst. One possible reason is that those caught up in a bubble are completely blinded by the grip, the overpowering logic and force excerted by the positive feedback loop that drives it. Financial bubbles occur time and time again - and nobody seems to learn. Another example on a different time scale is an argument that spins out of control and ends in violence. The participants seem to be blind to the consequences; the immediate and imperative logic of the feedback loop imposes itself. The vortex created by the feedback loop even seems to draw in outsiders, such as new investors. Is this the reason why we don't notice bubbles? This explanation is meant to stimulate discussion!

Ocean/atmosphere/biosphere model tuned for interactive economics-based simulations from Y2k on.

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.) It also, unlike Models 2 & 3, shows the influence Savings has on the production rate.

In summary, lower rates of consumption (based on production) result in higher rates of both production and consumption in the long-run.

not a mathematical model. just a general one

Smithian growth model from Michael Joffe Fig. 3.7 p57 Ch3 Feedback Economics Book

Just need to add sensitivity testing and storytelling, as well as make simulation displays for each thing we want to show

Also, everything in the agent folder cannot be displayed as its own primitive, so you can't see their individual outputs. We need to make agent states that simply have the [primitive title] as their code.

Ocean/atmosphere/biosphere model tuned for interactive economics-based simulations from Y2k on.

This Model was developed from the SEIR Model (Susceptible, Exposed, Infected, Recovered) and it predicts the COVID-19 outbreak in Burnie, Tasmania. This pandemic outbreak contributes to diverse rates including infection rate, death rates and recovery rate, government policies and its economic impacts.    

Assumptions:

 This model is driven by its determined rates, e.g., incubation rate, morality rate, test rate and immunity loss rate and its recovery rate.

Government policies are involved in fully vaccination rate, social distance, national border closure, travel, and business restriction which effect Burnie’s economy.

There are three economic entities dimensions in Burnie Island, we can tell that the pandemic has negative impact on Brick-and-Mortar enterprises and tourism business to some extent, whereas, e commercial business plays a crucial role to stimulate the regional economic activities during the COVID-19 period.

 

Interesting Insights:

 The figure of susceptible changes significantly during the initial 3 weeks because of low recovery rate and high infection rate. On the other hand, the implementation and interventions of government policies is effective, because the number of patients who tested negative is increased and the majority of them release and go back home after medical follow-up. 

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

This model demonstrate how the exisitng tested COVID cases effects economic recovery via goverment intervenes.

Model-SIM from Chapter 3 of Wynn Godley and Marc Lavoie's Monetary Economics, adapted for an open economy. The model is stock-flow consistent with only government money--no bills or bonds. No central bank and interest rates do not change. Government spends buying output from the production sector. The production sector is passive turning over all revenue over to households. Households save out of income and spend partially spend out of wealth. Imports and exports pass through the production sector illustrating the idea that consumer households buy from domestic businesses that which they have imported. The model also tracks the sectoral balance flows and changes in equity. Sectoral flows and equity balances match each other dollar for dollar to satisfy the sectoral balances accounting identity (Household Saving - Consumption) + (Business Saving - Expenditure) + (Taxes - Government Spending) - (Exports - Imports) = 0. Since business investment occurs internally to the Business Sector, 

The concept of 'CLOSING A FEEDBACK LOOP'  means that a loop is closed to affect the person or agents that originally are  responsible for an action so that they plainly feel its effects. This almost inevitable leads to corrective action. One of the reasons why climate change does not  arouse passion and action is that it is largely invisible and most people are not aware of it, although extreme weather events are beginning to change this somewhat. The schematic representation shows how systems thinking might help to draw attention to such situations by graphically connecting the dots to promote understand and hopefully action when people realize that there is a price to be paid for inaction.  Please note, however, that the loop does not describe dynamic behaviour in the normal system dynamics sense. 

I made this model to simulate how a companies revenue will change depending on the lifetime of the appliances it manufactures, in combination with the ratio of repair costs and price. It also shows the accumulation of e-waste.