Use a bathtub model to investigate the manner in which inflows and outflows govern the quantity of a stock. Extend the structure to create and investigate the relationships of a goal seeking balancing loop.
Part 1 demonstrates Picture primitives and Links to create representations of interactions. These are made visually attractive because the Picture primitives are overlay'd with images.
The limits to growth structure is based on the basic growth structure. And, as should be obvious, nothing grows forever as growth requires resources. Those required resources become a limits to growth.
The simple savings account is used to demonstrate the nature of a reinforcing loop. Change the initial amount and interest rate and run the model to see the implications of changing these values.
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. See also Archetypes.
We often set out to solve a problem or accomplish some particular result and things seem to go as planned. As time progresses it seems that progress becomes more and more difficult, if not impossible, and things may actually become worse than when we started. When this happens it is typically a Fixes that Fail structure that's operating. See also Archetypes.
A spatially aware, agent based model of disease spread. There are three classes of people: susceptible (healthy), infected (sick and infectious), and recovered (healthy and temporarily immune).
We begin with a Bank with $0 and Borrowers with $100. Every year the Bank loans the Borrowers money at some interest rate. If the Bank loans $50 at 10% interest in 20 years the bank will have all the money and the Borrowers will be broke.
Admittedly this model was designed to take the interaction to the extreme to demonstrate the extended implication of the interaction.
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. See also Archetypes.
