Counterbalance Economics

globals
[
  max-grain    ; maximum amount any patch can hold
  gini-index-reserve
  lorenz-points


]

patches-own
[
  grain-here      ; the current amount of grain on this patch
  max-grain-here  ; the maximum amount of grain this patch can hold

 ]

turtles-own
[
  age              ; how old a turtle is
  wealth           ; the amount of grain a turtle has
  life-expectancy  ; maximum age that a turtle can reach
  metabolism       ; how much grain a turtle eats each time
  vision           ; how many patches ahead a turtle can see
  Tax-Collected    ; Amount of wealth reduced by tax
  Welfare          ; Amount received as welfare payment

]

breed [cooperative-turtles cooperative-turtle]
breed [rich-turtles rich-turtle]


;;;
;;; SETUP AND HELPERS
;;;

to setup
  clear-all
  ;; set global variables to appropriate values
  set max-grain 50
  ;; call other procedures to set up various parts of the world
  setup-patches
  setup-turtles
  update-lorenz-and-gini

  reset-ticks
end 

;; set up the initial amounts of grain each patch has

to setup-patches
  ;; give some patches the highest amount of grain possible --
  ;; these patches are the "best land"
  ask patches
    [ set max-grain-here 0
      if (random-float 100.0) <= percent-best-land
        [ set max-grain-here max-grain
          set grain-here max-grain-here ] ]
  ;; spread that grain around the window a little and put a little back
  ;; into the patches that are the "best land" found above
  repeat 5
    [ ask patches with [max-grain-here != 0]
        [ set grain-here max-grain-here ]
      diffuse grain-here 0.25 ]
  repeat 10
    [ diffuse grain-here 0.25 ]          ;; spread the grain around some more
  ask patches
    [ set grain-here floor grain-here    ;; round grain levels to whole numbers
      set max-grain-here grain-here      ;; initial grain level is also maximum
      recolor-patch ]
end 

to recolor-patch  ;; patch procedure -- use color to indicate grain level
  set pcolor scale-color yellow grain-here 0 max-grain
end 

;; set up the initial values for the turtle variables

to setup-turtles
  set-default-shape turtles "person"
  create-turtles num-people
    [ move-to one-of patches  ;; put turtles on patch centers
      set size 1.5  ;; easier to see
      set-initial-turtle-vars
      set age random life-expectancy ]
  recolor-turtles
end 

to set-initial-turtle-vars
  set age 0
  face one-of neighbors4
  set life-expectancy life-expectancy-min +
                        random (life-expectancy-max - life-expectancy-min + 1)
  set metabolism 1 + random metabolism-max
  set wealth metabolism + random 50
  set vision 1 + random max-vision
  set Tax-Collected (wealth * Tax-Collected-as-%-of-GDP)
  set Welfare (Tax-Collected * Welfare-Payment-to-Reds)
end 


;; Set the class of the turtles -- if a turtle has less than a third
;; the wealth of the richest turtle, color it red.  If between one
;; and two thirds, color it green.  If over two thirds, color it blue.
;; setup recolor based on chooser

to recolor-turtles
  let max-wealth max [wealth] of turtles

 ;; when chosen, this component returns this simulation back to its original setting to provide a baseline for comparison
  if ( Economic-System = "Original-Model" ) [ ask turtles [ ifelse (wealth <= max-wealth / 3)
        [ set color red ]
        [ ifelse (wealth <= (max-wealth * 2 / 3))
            [ set color green ]
      [ set color blue ] ] ]]


 ;; when chosen, this component simulates paying the bottom 50% of workers the AWE amount which in this simulation is the Average Total Wealth
  if ( Economic-System = "Counterbalance" ) [ ask turtles [ ifelse (wealth <= max-wealth / 3)
        [ set color red set wealth (avg-inc-total * CBE-Contra-Deal-Credit-AWE-Payment) ] ;; this line simulates paying the reds the AWE amount in Contra-Deal Credits
        [ ifelse (wealth <= (max-wealth * 2 / 3))
            [ set color green ] ;; In the CBE, everyone has a job, therefore, no unemployment benefits are required.
      [ set color blue ] ] ]] ;; therefore, governments can reduce the amount of tax paid by the greens and the blues
  ;; It is envisaged that any money saved, will be put back into the economy and that is simulated by reducing the tax rate to 1/3 of the normal tax rate for the greens and the blues

 ;; when chosen, this component allows you to vary the overall tax rate and the welfare paid to the reds
  if ( Economic-System = "Neoliberal-v-GovernmentRun" ) [ ask turtles [ ifelse (wealth <= max-wealth / 3)
    [ set color red set wealth ((wealth + Welfare) - Tax-Collected) ]
        [ ifelse (wealth <= (max-wealth * 2 / 3))
            [ set color green set wealth (wealth - Tax-Collected) ]
      [ set color blue set wealth (wealth - Tax-Collected) ] ] ]]
end 


;; Set the type of turtles -- if a turtle has less two thirds or less
;; then it is cooperative.
;; If over two thirds, then it is a rich turtle.

to setup-turtles-breeds
  let max-wealth max [wealth] of turtles
  ask turtles
    [ ifelse (wealth <= max-wealth * 2 / 3)
        [ set breed cooperative-turtles
      set color green ]
        [ set breed rich-turtles
      set color red ] ]
end 


;;;
;;; GO AND HELPERS
;;;

to go

if ticks >= 500 [ stop ]
  ask turtles
  [ turn-towards-grain ]  ;; choose direction holding most grain within the turtle's vision
  harvest
  ask turtles
    [ move-eat-age-die ]

recolor-turtles

  ;; grow grain every grain-growth-interval clock ticks
  if ticks mod wealth-growth-time = 0
    [ ask patches [ grow-grain ]]



  update-lorenz-and-gini

tick
end 


;; determine the direction which is most profitable for each turtle in
;; the surrounding patches within the turtles' vision

to turn-towards-grain  ;; turtle procedure
  set heading 0
  let best-direction 0
  let best-amount grain-ahead
  set heading 90
  if (grain-ahead > best-amount)
    [ set best-direction 90
      set best-amount grain-ahead ]
  set heading 180
  if (grain-ahead > best-amount)
    [ set best-direction 180
      set best-amount grain-ahead ]
  set heading 270
  if (grain-ahead > best-amount)
    [ set best-direction 270
      set best-amount grain-ahead ]
  set heading best-direction
end 

to-report grain-ahead  ;; turtle procedure
  let total 0
  let how-far 1
  repeat vision
    [ set total total + [grain-here] of patch-ahead how-far
      set how-far how-far + 1 ]
  report total
end 

to grow-grain  ;; patch procedure
  ;; if a patch does not have it's maximum amount of grain, add
  ;; num-grain-grown to its grain amount
  if (grain-here < max-grain-here)
    [ set grain-here grain-here + wealth-growth-volume
      ;; if the new amount of grain on a patch is over its maximum
      ;; capacity, set it to its maximum
      if (grain-here > max-grain-here)
        [ set grain-here max-grain-here ]
      recolor-patch ]
end 


;; each turtle harvests the grain on its patch.  if there are multiple
;; turtles on a patch, divide the grain evenly among the turtles

to harvest
  ; have turtles harvest before any turtle sets the patch to 0
  ask turtles
    [ set wealth floor (wealth + (grain-here / (count turtles-here) )) ]

  ;; now that the grain has been harvested, have the turtles make the
  ;; patches which they are on have no grain
  ask turtles
    [ set grain-here 0
      recolor-patch ]
end 

to move-eat-age-die  ;; turtle procedure
  fd 1

  set Tax-Collected (wealth * Tax-Collected-as-%-of-GDP)
  set Welfare (Tax-Collected * Welfare-Payment-to-Reds)

  ;; consume some grain according to metabolism
  set wealth (wealth - metabolism)
  ;; grow older
  set age (age + 1)
  ;; check for death conditions: if you have no grain or
  ;; you're older than the life expectancy or if some random factor
  ;; holds, then you "die" and are "reborn" (in fact, your variables
  ;; are just reset to new random values)
  if (wealth < 0) or (age >= life-expectancy)
    [ set-initial-turtle-vars ]
end 

;; this procedure recomputes the value of gini-index-reserve
;; and the points in lorenz-points for the Lorenz and Gini-Index plots

to update-lorenz-and-gini
  let sorted-wealths sort [wealth] of turtles
  let total-wealth sum sorted-wealths
  let wealth-sum-so-far 0
  let index 0
  set gini-index-reserve 0
  set lorenz-points []

  ;; now actually plot the Lorenz curve -- along the way, we also
  ;; calculate the Gini index.
  ;; (see the Info tab for a description of the curve and measure)
  repeat num-people [
    set wealth-sum-so-far (wealth-sum-so-far + item index sorted-wealths)
    set lorenz-points lput ((wealth-sum-so-far / total-wealth) * 100) lorenz-points
    set index (index + 1)
    set gini-index-reserve
      gini-index-reserve +
      (index / num-people) -
      (wealth-sum-so-far / total-wealth)
      ]
end 

to-report num-of-red
  report round count turtles with [color = red]
end 

to-report num-of-green
  report round count turtles with [color = green]
end 

to-report num-of-blue
  report round count turtles with [color = blue]
end 

to-report avg-inc-red
    report round sum [ wealth ] of turtles with [color = red] / num-of-red
end 

to-report avg-inc-green
    report round sum [ wealth ] of turtles with [color = green] / num-of-green
end 

to-report avg-inc-blue
    report round sum [ wealth ] of turtles with [color = blue] / num-of-blue
end 

to-report avg-inc-total
  report (sum [wealth] of turtles) / num-people
end 

to-report tot-wealth-world
  report round sum [ max-grain ] of patches + sum [wealth] of turtles
end 




; Copyright 1998 Uri Wilensky.
; See Info tab for full copyright and license.