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## WHAT IS IT?

coinGame:
a simulation of Ole Peters (London Mathematical Laboratory) coin game to show effects of the wrong ergodic hypothesis in traditional economics and the benefits of cooperation thru wealth-tax, see:
https://ergodicityeconomics.files.wordpress.com/2018/06/ergodicity_economics.pdf

## HOW IT WORKS

some turtles play the coingame. Each of them throws a coin for each tick:
if heads are shown, individual wealth is multiplied by mult-heads and add-heads is added.
if tails are shown, individual wealth is multiplied by mult-tails and add-tails is added.
If tax-factor is > 0 and wealth is > tax-limit a wealth tax (wealth * tax-factor) is subtracted and the mean tax amount is added. the collected wealth tax is redistributed evenly, so we simulate cooperation thru risk-sharing

## HOW TO USE IT

use the sliders to control the number of turtles, mult-heads mult-tails and add-heads, add-tails, optional set a tax-factor and a tax-limit,
If you want bancrupt turtles to die, set turtles-die? to on, then press setup.
To play one round press go-1, to play as long as you wish, press go.

## THINGS TO NOTICE

on the black plot area you see at setup all turtles sorted by id (who) as x-coord and with y-coord = 1 = wealth. Each turtle will go up or down vertically dependent of its current wealth after each tick.
In the wealth-plot you see min, max, mean and median of the turtles wealth on a log10 scale.
In the wealth-distribution histogramm you see the number of turtles in different classes of wealth.

## THINGS TO TRY

try different values for multiplicative growth (heads-mult, tails-mult) vs additive growth (heads-add and tails-add)
compare the wealth-distribution for only additive growth (set both heads-mult, tails-mult to 1.0) to only multiplicative growth (set both heads-add and tails-add to 0.0)
try diffenet tax-factors, what effects of the the taxfactor can you see in the histogram?

## EXTENDING THE MODEL

better visualization ideas?
correct logic of log10 plot (log abs is a dirty fix for negative wealth)

## NETLOGO FEATURES

plotting on a log scale,
using turtle world to show turtle ranking by position,
histogram on varying upper and lower bounds

## RELATED MODELS

http://ccl.northwestern.edu/netlogo/models/WealthDistribution
http://ccl.northwestern.edu/netlogo/models/Sugarscape3WealthDistribution

## CREDITS AND REFERENCES

Author: Rupert Nagler, Jan 2020, nagler@idi.co.at

https://ergodicityeconomics.files.wordpress.com/2018/06/ergodicity_economics.pdf
https://en.wikipedia.org/wiki/Ergodicity
https://www.farmersfable.org/

## COPYRIGHT

Copyright 2020 Rupert Nagler. All rights reserved.
Permission to use, modify or redistribute this model is hereby granted, provided that both of the following requirements are followed:
a) this copyright notice is included.
b) this model will not be redistributed for profit without permission from Rupert Nagler. Contact the author for appropriate licenses for redistribution for profit.