World3

State

class whynot.simulators.world3.State[source]

World3 state.

Default values correspond to the initial state in 1900 of the standard run.

Examples

>>> # Construct initial state with 800 land fertility.
>>> world3.State(arable_land=800)
arable_land = 900000000.0
industrial_capital = 210000000000.0
land_fertility = 600.0
nonrenewable_resources = 1000000000000.0
persistent_pollution = 25000000.0
population_0_to_14 = 650000000.0
population_15_to_44 = 700000000.0
population_45_to_64 = 190000000.0
population_65_and_over = 60000000.0
potentially_arable_land = 2300000000.0
service_capital = 144000000000.0
total_population

Return the aggregate population.

urban_industrial_land = 8200000.0

Config

class whynot.simulators.world3.Config[source]

World3 simulation dynamics parameters.

Default values correspond to the standard run of World3.

Examples

>>> # Configuration of a run from 1910-1950
>>> world3.Config(start_time=1910, end_time=1950)
average_lifetime_of_industrial_capital = 14
average_lifetime_of_service_capital = 20
delta_t = 1.0

Granularity of the simulation (step size in the forward Euler method).

end_time = 2100

Year to end the simulation.

fraction_of_industrial_output_allocated_to_consumption_constant = 0.43
industrial_capital_output_ratio = 3
land_yield_factor = 1
nonrenewable_resource_usage_factor = 1
persistent_pollution_generation_factor = 1
service_capital_output_ratio = 1
start_time = 1900

Year to start the simulation.

Interventions

class whynot.simulators.world3.Intervention(time=1975, **kwargs)[source]

Parameterization of an intervention in the World3 model.

An intervention is a subset of the configuration variables, and only variables passed into the constructor are modified.

Examples

>>> # Semantics: Starting in year 1975, double land_yield. All
>>> # other parameters are unchanged.
>>> Intervention(time=1975, land_yield_factor=2)
__init__(time=1975, **kwargs)[source]

Construct an intervention object.

Parameters:
  • time (float) – time (in years) to intervene in the simulator.
  • kwargs (dict) – Only valid keyword arguments are parameters of Config.

Experiments

Experiments for world3 simulator.

whynot.simulators.world3.experiments.PollutionRCT = PollutionRCT

An RCT experiment to study the effect of decreases in pollution generation on population.

whynot.simulators.world3.experiments.PollutionConfounding = PollutionConfounding

An observational experiment with confounding. Polluted states are more likely to be treated.

whynot.simulators.world3.experiments.PollutionUnobservedConfounding = PollutionUnobservedConfounding

An observational experiment with unobserved confounding.

whynot.simulators.world3.experiments.PollutionMediation = PollutionMediation

An observational experiment with mediation from states after intervention.