Rumor Model from Qualitative Observations

;; local population is always static
;; volunteers arrive and depart as a function of migrant arrivals and departures

;; agents wander randomly through the world
;; random numbers (user-defined) of the population of migrants and volunteers
;;     commit norms violations that the locals don't like. (not liking isn't in code yet)
;; locals witness these violations
;; violations and witnessing are reset at each tick (instances are fleeting)

;; I added an experience variable to count the number of events witnessed, but it's not used right now
;; added networks

globals
[
  ;; Local-Population ;; population is static and defined by user
  ;; Migrant-Arrival-Rate ;; is a slider that can be adjusted for number of migrants arriving per day (tick)
  ;; Volunteer-Arrival-Rate ;; is a slider adjusted by user defining a percentage of volunteers based on refugee arrivals
  ;; Vision ;; controls how far away the locals can see a transgression (measured in patches)
  ;; Migrant-Weight ;; how much weight a local places on witnessing a migrant transgression to change opinion of them
  ;; Volunteer-Weight ;; how much weight a local places on witnessing a volunteer transgression to change opinion of them
  ;; Influence ;; controls how far away locals look to neighbors for a rumor
  ;; Networks ;; networks on or off
  Volunteer-incidents ;; infractions by volunteers
  Migrant-incidents ;; infractsions by migrants
]

breed [ migrants migrant ]
breed [ volunteers volunteer ]
breed [ locals local ]

locals-own [
  migrant-feelings ;; heterogeneous, normal, (0,1) feelings about refugees
  volunteer-feelings ;; heterogeneous, normal, (0,1) feelings about volunteers
  migrant-witness? ;; have witnessed a norm violation by refugee in this tick
  volunteer-witness? ;; have witnessed a norm violation by volunteer in this tick
  experience ;; a count of how many events the local has witnessed
  migrant-rumor-holder? ;; the equivalent of "infected" in SIR model
  volunteer-rumor-holder? ;; the equivalent of "infected" in SIR model -- like there are two related diseases
  friends ;; number of friends in network
]

turtles-own [
 transgressor?
]

to setup
  ca
  reset-ticks
  create-locals Local-Population
  [
    set color blue
    set shape "circle 2"
    ;; feelings along a normal distribution with mean 0, s.d. 1
    set migrant-feelings random-normal 0 1
    set volunteer-feelings random-normal 0 1
    set migrant-rumor-holder? 0
    set volunteer-rumor-holder? 0
    set friends 0
    setxy random-xcor random-ycor ;; distribute around the environment
  ]

  if Networks = True [
    ask locals [
      set friends random-normal ( Local-Population / 5) ( Local-Population * .05 ) ;; version of normal dist
      create-links-to up-to-n-of friends other locals
      set friends count my-links
    ]
    ask links [ hide-link ]
  ]
end 

to go
  if ticks = 300 [ stop ]
  reset-violations
  reset-witness
  get-over-it

  outsiders-arrive
  violate-norm
  update-global-counters
  wander
  witness
  spread-rumor
  outsiders-leave

  tick
end 

to update-global-counters
  set Volunteer-incidents Volunteer-incidents + count volunteers with [transgressor? = 1 ]
  set Migrant-incidents Migrant-incidents + count migrants with [ transgressor? = 1 ]
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;; population arrival and departure code ;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to outsiders-arrive
  create-migrants Migrant-Arrival-Rate [ set color red ]
  ask migrants [ setxy random-xcor random-ycor ]

  ;; this makes volunteers arrive at a proportion of refugee arrivals
  let volunteer-draw int (Migrant-Arrival-Rate * (Volunteer-Arrival-Rate / 100) )
  create-volunteers volunteer-draw [ set color green set shape "square 2"]

  ask volunteers [ setxy random-xcor random-ycor ]
end 

to outsiders-leave
  ask up-to-n-of Migrant-Departure-Rate migrants [ die ]

  let volunteer-sad int (Migrant-Departure-Rate * (Volunteer-Departure-Rate / 100))
  ask up-to-n-of volunteer-sad volunteers [ die ]
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;; norm violation code ;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to violate-norm
  let integer random Transgression-Rate

  ask up-to-n-of integer migrants [ set shape "x" set size 2 set color yellow set transgressor? 1 ]
  ask up-to-n-of (Transgression-Rate - integer) volunteers [ set shape "x" set size 2 set color yellow set transgressor? 1 ]
end 

to reset-violations
  ask migrants with [transgressor? = 1] [ set shape "default" set size 1 set color red set transgressor? 0 ]
  ask volunteers with [transgressor? = 1] [ set shape "square 2" set size 1 set color green set transgressor? 0 ]
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;; population movement code ;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to wander
  ask turtles [ left random 180 fd 1 ]
end 

to witness
  ask locals [
    if count migrants with [ transgressor? = 1 ] in-radius Vision >= 1
    [
      set migrant-witness? 1
      set experience experience + 1
      set migrant-rumor-holder? 1
      update-migrant-feelings
      if Networks = True [ ask out-link-neighbors [ catch-migrant-rumor ] ] ;; it's not a direct spread, they "catch" it through SIR
    ]
    if count volunteers with [ transgressor? = 1 ] in-radius Vision >= 1
    [
      set volunteer-witness? 1
      set experience experience + 1
      set volunteer-rumor-holder? 1
      update-volunteer-feelings
      if Networks = True [ ask out-link-neighbors [ catch-volunteer-rumor ] ] ;; it's not a direct spread, they "catch" it through SIR
    ]

  ]
end 

to reset-witness
  ask locals with [migrant-witness? = 1 ] [ set migrant-witness? migrant-witness? = 0 ]
  ask locals with [volunteer-witness? = 1 ] [ set volunteer-witness? volunteer-witness? = 0 ]
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;; updating locals' feelings code ;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;note here that feelings only update in the negative for norm violations
;; adjusts differently for migrants and volunteers to try to capture locals' empathy for certain groups

to update-migrant-feelings
  set migrant-feelings migrant-feelings - 0.1 * Migrant-Weight
end 

to update-volunteer-feelings
  set volunteer-feelings volunteer-feelings - 0.1 * Volunteer-Weight
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;; SIR/ Rumor Spread code ;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to spread-rumor
  let susceptibles locals with [ migrant-rumor-holder? = 0 OR volunteer-rumor-holder? = 0 ]
  ask susceptibles [
    if count locals with [ migrant-rumor-holder? = 1 ] in-radius Influence >= 1 [ catch-migrant-rumor ]
    if count locals with [ volunteer-rumor-holder? = 1 ] in-radius Influence >= 1 [ catch-volunteer-rumor ]
    ]
end 

to catch-migrant-rumor
  let coin random 100 ;; select a random number, uniform distribution
  if coin <= Probability-Spread [
    set shape "circle"
    set migrant-rumor-holder? 1
    update-migrant-feelings
  ]
end 

to catch-volunteer-rumor
  let coin random 100 ;; select a random number, uniform distribution
  if coin <= Probability-Spread [
    set shape "circle"
    set volunteer-rumor-holder? 1
    update-volunteer-feelings
  ]
end 

to get-over-it
  let infected locals with [ migrant-rumor-holder? = 1 OR volunteer-rumor-holder? = 1 ]
  ask infected [
    let coin random 100 ;; select a random number, uniform distribution
    if coin <= Probability-Recover [
      ifelse migrant-rumor-holder? = 1
      [ set migrant-rumor-holder? 0 ]
      [ set volunteer-rumor-holder? 0 ] ;;NOTE THAT THERE IS A PRIORITIZATION HERE AND THAT SOME AGENTS WILL HAVE BOTH TRUE -- NEED TO UPDATE
      set shape "circle 2"
      ;;user-message "got better!"
    ]
  ]
end