"Club goods and social interaction."

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Here you can find an introduction to the Club goods and social interaction application.

view/download model file: club_goods_and_social_interaction.nlogo

WHAT IS IT?

(a general understanding of what the model is trying to show or explain)

HOW IT WORKS

(what rules the agents use to create the overall behavior of the model)

HOW TO USE IT

(how to use the model, including a description of each of the items in the Interface tab)

THINGS TO NOTICE

(suggested things for the user to notice while running the model)

THINGS TO TRY

(suggested things for the user to try to do (move sliders, switches, etc.) with the model)

EXTENDING THE MODEL

(suggested things to add or change in the Code tab to make the model more complicated, detailed, accurate, etc.)

NETLOGO FEATURES

(interesting or unusual features of NetLogo that the model uses, particularly in the Code tab; or where workarounds were needed for missing features)

RELATED MODELS

(models in the NetLogo Models Library and elsewhere which are of related interest)

CREDITS AND REFERENCES

(a reference to the model’s URL on the web if it has one, as well as any other necessary credits, citations, and links)

CODE

globals [space]

breed [agents agent]
agents-own [benefit cost]

to setup
  
   clear-all
   setup-patches
   setup-agents
   reset-ticks

end

to setup-patches
  
   ask patches [
     if pxcor >= 0 and pycor <= 0 [set pcolor green]
     if pxcor <= 0 and pycor <= 0 [set pcolor green]
     ]

end

to setup-agents
   
   create-agents number-agents
   ask agents [
     setxy (-16 + random 33) (1 + random 16)
     set shape "person"
     set color red  
     set benefit nonmembers-benefit
     set cost nonmembers-price-per-visit
     ]
    
    ask n-of number-members agents [
     setxy random-xcor random-ycor
     set color yellow
     set cost members-price-per-visit
     set benefit (members-benefit + (Fee / periodicity-of-fee))
     ]
    
end

to go
  
   move-agents
   modify-status
   do-plots
   tick

end

to move-agents
  
  ask agents with [color = yellow and pcolor = green] [
      if random-float 1 < members-prob-exit 
      or (economic-comparison? and random 50 < members-price-per-visit
      and random 50 >= members-benefit + (Fee / periodicity-of-fee))[move-to patch (-16 + random 33)(1 + random 16)]
      ]
    
    ask agents with [color = yellow and pcolor = black] [
      if random-float 1 < members-prob-enter
      or (economic-comparison? and random 50 > members-price-per-visit
      and random 50 <= members-benefit + (Fee / periodicity-of-fee))[move-to patch (-16 + random 33)(-1 - random 16)]
      ]
    
    ask agents with [color = red and pcolor = green] [
      if random-float 1 < nonmembers-prob-exit
      or (economic-comparison? and random 50 < nonmembers-price-per-visit 
      and random 50 >= nonmembers-benefit) [move-to patch (-16 + random 33)(1 + random 16)]
      ]
    
    ask agents with [color = red and pcolor = black] [
      if random-float 1 < nonmembers-prob-enter
      or (economic-comparison? and random 50 > nonmembers-price-per-visit 
      and random 50 <= nonmembers-benefit) [move-to patch (-16 + random 33)(-1 - random 16)]
      ]

end

to modify-status
 
  set number-members (count agents with [color = yellow and pcolor = green] + count agents with [color = yellow and pcolor = black])
  ;;set number-members count agents with [color = yellow] 
   
   ask agents with [color = red and pcolor = black] [
     if social-effects? and any? agents with [color = yellow and pcolor = black] in-radius 2 [
       set color yellow
       ]
     ]
   
   ask agents with [color = yellow and pcolor = green] [
     if social-effects? and count agents with [pcolor = green] >= (number-agents / 2) [
       set color red
       set nonmembers-benefit random 10
       set members-benefit random 10
       ]
     ]
   
    ask agents with [color = yellow and pcolor = green] [
     if social-effects? and count agents with [pcolor = green] <= (number-agents / 15) [
       set color red
       set nonmembers-benefit random 10
       set members-benefit random 10
       ]
     ]
        
end

to do-plots
   
   set-current-plot "total members"
   set-current-plot-pen "members in club" 
   plot count agents with [color = yellow and pcolor = green] 
   set-current-plot-pen "members outside club"
   plot count agents with [color = yellow and pcolor = black]
   
   set-current-plot "total nonmembers"
   set-current-plot-pen "nonmembers in club"
   plot count agents with [color = red and pcolor = green]
   set-current-plot-pen "nonmembers outside club"
   plot count agents with [color = red and pcolor = black]

end