ABM of Behaviour, Risk and Harassment in Public Transport

globals [
  percent-similar
  percent-unhappy
  total-reports       ;; total number of harassment reports
  total-incidents     ;; total number of harassment incidents
  total-interventions ;; bystander interventions
  perceived-safety-index ;; average safety level across all non-harasser agents
  
  women-harassment-incidents          ;; all incidents to women victims
  men-harassment-incidents            ;; all incidents to men victims
  gender-diverse-harassment-incidents ;; all incidents to gender-diverse victims
]

turtles-own [
  role
  fear        ;; 0 to 1
  trust       ;; 0 to 1
  awareness   ;; 0 to 1
  gender      ;; only assigned to victims
  was-harassed?  ;; true if this victim has ever been harassed
]

to-report harassment-risk-factor
  ;; U-shaped curve: risk is high near 0 and 1, lowest near 0.5
  report (6 * (location-crowdedness - 0.5) ^ 2)
end 

to setup
  clear-all
  set total-interventions 0
  set total-incidents 0
  set total-reports 0
  set women-harassment-incidents 0
  set men-harassment-incidents 0
  set gender-diverse-harassment-incidents 0
  
  create-turtles 200 [
    setxy random-xcor random-ycor
    set role one-of ["victim" "bystander" "harasser" "staff"]

;; Assign role-based colours only
set color ifelse-value role = "harasser" [yellow]
         [ifelse-value role = "bystander" [blue]
         [ifelse-value role = "victim" [green] [Pink]]]

    ;; Randomised individual states
    set fear random-float 1
    set trust random-float 1
    set awareness random-float 1
    
    ;; default
    set was-harassed? false
   
    ;; Assign gender only to victims
if role = "victim" [
  set gender one-of ["woman" "man" "gender-diverse"]
  set shape ifelse-value gender = "woman" ["circle"]
            [ifelse-value gender = "man" ["square"] ["star"]]  ;; for gender-diverse
]
        
  ;; Set gender-specific starting fear
  if gender = "woman" [ set fear 0.7 ]
  if gender = "gender-diverse" [ set fear 0.6 ]
  if gender = "man" [ set fear 0.3 ]
]

  reset-ticks
end 

; run the model for one tick

to go
  ask turtles [

;; HARASSER behaviour
if role = "harasser" [
      
  ;; Adjust base risk
  let time-risk ifelse-value (time-of-day >= 20 or time-of-day <= 6) [1.2] [0.8]
  let gender-risk-multiplier 1.0

;; Check for nearby victims
let nearby-victims other turtles in-radius 2 with [role = "victim"]
if any? nearby-victims [
  let victim one-of nearby-victims
   
  ;; Adjust risk based on victim gender     
  set gender-risk-multiplier 
    ifelse-value [gender] of victim = "woman" [2.0]
    [ifelse-value [gender] of victim = "gender-diverse" [1.5] [0.9]]

  
  let policy-reduction (1 + enforcement-level + infrastructure-quality + awareness-campaign-intensity)
  let base-risk (harassment-risk-factor * (1 - trust) * time-risk * gender-risk-multiplier / policy-reduction)
    
  if random-float 1 < base-risk [
    set color red  ;; flash on harassment
    set total-incidents total-incidents + 1
    
   ;; mark this victim as harassed and count incident by gender    
   ask victim [
     set was-harassed? true
            if gender = "woman" [
              set women-harassment-incidents women-harassment-incidents + 1
            ]
            if gender = "man" [
              set men-harassment-incidents men-harassment-incidents + 1
            ]
            if gender = "gender-diverse" [
              set gender-diverse-harassment-incidents
                gender-diverse-harassment-incidents + 1
            ]
          ]
        ]
      ]

  ;; Reset colour if not harassing
  if color != red [ set color yellow ]
]

    ;; BYSTANDER behaviour
     if role = "bystander" [
       let nearby-harassers other turtles in-radius 1 with [role = "harasser"]
       if any? nearby-harassers [
         if random-float 1 < intervention-probability [
          set color cyan
          set trust trust + 0.1
          set total-interventions total-interventions + 1
        ]
       ]
      ]

    ;; VICTIM behaviour
    if role = "victim" [
    let gender-multiplier
    ifelse-value gender = "woman" [2.0]
    [ifelse-value gender = "gender-diverse" [1.5] [0.9]]  ;; default for man

    let nearby-harassers other turtles in-radius 1 with [role = "harasser"]
      if any? nearby-harassers [
        if random-float 1 < (trust * awareness * gender-multiplier) [
        set color lime
        set total-reports total-reports + 1
    ]
  ]
]

;; STAFF behaviour
if role = "staff" [
  let nearby-agents other turtles in-radius 1

  ;; NEW: respond only with some probability      
      if random-float 1 < intervention-probability [
  set color violet  ;; intervene flash
  ask nearby-agents [
    set trust trust + 0.05
    set fear fear - 0.05
  ]
]
if color != violet [ set color pink ]


  ;; Optional: continue patrolling
  right random 360
  forward 1
    ]
]
  
    ;; Awareness update – must be outside the previous block!
  ask turtles [
    set awareness min (list 1 (awareness + awareness-campaign-intensity))
  ]
ask turtles [
  set trust min (list 1 (trust + enforcement-level))
  set fear max (list 0 (fear - enforcement-level))
]
  ask turtles [
  set trust min (list 1 (trust + infrastructure-quality))
  set fear max (list 0 (fear - infrastructure-quality))
]
 ;;MOVEMENT FOR ALL NON-STAFF AGENTS
  ask turtles with [role != "staff"] [
    rt random 360
    fd 1
  ]

  ;; Adjust states based on time of day
let night? (time-of-day >= 20 or time-of-day <= 6)

ask turtles [
  if night? [
    set awareness awareness * 0.8
    set fear min (list 1 (fear + 0.1))
  ]
]
  tick
  ;; perceived safety index
  let relevant-agents turtles with [role != "harasser"]
  let total-score sum [ (1 - fear + trust + awareness) / 3 ] of relevant-agents
  set perceived-safety-index total-score / count relevant-agents
  update-plots
end 

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