Optimising Compensation

; Employee Compensation Optimisation Simulation

; Define global variables.
globals [
  successful-job-changes    ; The number of successful job changes.
  successful-negotiations   ; The number of successful negotiations.
  initial-salary            ; The salary (ZAR) that all agents will initially start with.
]

; Define agents.
breed [employers employer]
breed [employees employee]

; Define agent attributes.
employees-own [
  salary                    ; Monthly salary in ZAR.
  my-employer               ; Current employer.
  tenure                    ; Time spent with current employer.
  tendency                  ; Whether the employee tends to stay in the same job or change.
  tipping-point             ; The point at which an employee who tends to stay will change.
]

employers-own [
  num-jobs-available        ; Number of job openings currently available.
  workforce-needs           ; Number of employees needed to fulfil company needs.
  capacity                  ; Total number of employees company can have.
  my-employees              ; Agentset of employees.
]

; Set up routine.

to setup
  clear-all

  ; Initialise global variables.
  set successful-job-changes 0
  set successful-negotiations 0
  set initial-salary random-normal 50000 25000

  ; Create employers and position them in a grid in the top half.
  let employer-spacing (max-pxcor - min-pxcor) / (ceiling (sqrt num-employers) + 1)
  let employer-num 0

  create-employers num-employers [
    set shape "circle 2"
    set color yellow
    set capacity (random 96) + 5
    set workforce-needs random capacity
    set num-jobs-available 0
    set my-employees []
    set size 1

    ; Position the employer in a grid in the top half.
    let row floor (employer-num / ceiling (sqrt num-employers))
    let col employer-num mod ceiling (sqrt num-employers)
    let x-pos (col * employer-spacing) + min-pxcor + (employer-spacing / 2)
    let y-pos max-pycor - (row * employer-spacing) - (employer-spacing / 2) + 2
    setxy x-pos y-pos
    set employer-num employer-num + 1
  ]

  ; Create employees and position them in a grid in the bottom half.
  create-employees num-employees [
    set shape "person business"
    set color random color
    set salary 0
    set tenure 0
    set tendency one-of ["stay" "change"]
    set tipping-point random-float 0.15 + 0.15

    ; Position the employee in the bottom half.
    let x-pos random-xcor
    let y-pos random min-pycor
    setxy x-pos y-pos
  ]

  reset-ticks
end 

; Go routine.

to go

  ask employers [
    eval-workforce-needs
  ]

  let application-outcome random-float 1.0              ; Simulate application process.
  ask employees [
    if-else my-employer = 0 and application-outcome > 0.5 [                                     ; If unemployed, apply for job.
      seek-job
    ] [
      if-else tendency = "stay" [                       ; If employee tends to stay, only apply for job if salary increase is greater or equal to their tipping point.
        if-else application-outcome > 0.5 and salary-increase-changing-jobs >= tipping-point [  ; Application successful.
          seek-job
        ] [
          negotiate                                     ; Either appplication unsuccessful or salary increase is less than tipping point, so negotiate for raise.
        ]
      ] [                                               ; Else, employee tends to change so apply for job.
          if-else application-outcome > 0.5 [           ; Application successful.
            seek-job
          ] [
            negotiate                                   ; Application unsuccessful, so negotiate for raise.
          ]
      ]
      set salary max (list (salary * (1 - inflation)) 0)                                        ; Apply inflation, up to a min salary of 0.
    ]
  ]

  tick
end 

;;;;;;;;;;;;;;;;;;;;;; EMPLOYER ROUTINES ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to eval-workforce-needs
  if workforce-needs > length my-employees [                                                    ; First check if workforce needs are not being met.
    if length my-employees < capacity [                                                         ; If so, check that capacity hasn't been exceeded.
      set num-jobs-available workforce-needs - length my-employees                              ; Open a post.
    ]
  ]

  set size length my-employees / 4                                                              ; Update size of company, scaled down by 4 for visual display.
end 

;;;;;;;;;;;;;;;;;;;;;; EMPLOYEE ROUTINES ;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to seek-job
  if-else any? employers with [num-jobs-available > 0] [            ; Check if there are jobs available.
    let new-employer one-of employers with [num-jobs-available > 0] ; Choose one employer with available jobs.
    let old-employer my-employer
    set my-employer new-employer                                    ; Update my employer.

    ask new-employer [                                              ; Update new employer details.
      set num-jobs-available num-jobs-available - 1
      set my-employees fput myself my-employees
    ]

    if old-employer != 0 [
      ask old-employer [                                            ; Update old employer details.
        set num-jobs-available num-jobs-available + 1
        set my-employees remove myself my-employees
      ]
    ]

    if-else salary = 0 [                                            ; If unemployed, set salary to initial salary.
     set salary initial-salary
    ] [
      set salary min (list (salary * (1 + salary-increase-changing-jobs)) 1000000)    ; Update salary, up to a max of 1 million.
    ]

    move-to new-employer                                            ; Move to new employer and reset number of years at employer.
    set tenure 0

    set successful-job-changes successful-job-changes + 1           ; Increment number of job changes.
  ] [
    set salary min (list (salary * (1 + annual-salary-increase)) 1000000)             ; If no jobs available, update salary with annual increase, up to a max of 1 million.
    set tenure tenure + 1                                                             ; Increase number of years at employer.
  ]
end 

to negotiate
  let negotiation-outcome random-float 1.0                          ; Simulate negotiation process.

  if-else negotiation-outcome > 0.5 [                               ; Negotiation successful.
    set salary min (list (salary * (1 + salary-increase-negotiation)) 10000000)       ; Update salary, up to a max of 1 million.

    set successful-negotiations successful-negotiations + 1         ; Increment number of successful negotiations.
  ] [                                                               ; Negotiation unsuccessful.
    set salary min (list (salary * (1 + annual-salary-increase)) 1000000)             ; Update salary with annual increase, up to a max of 1 million.
  ]

  set tenure tenure + 1                                             ; Increase number of years at employer.
end 

;;;;;;;;;;;;;;;;;;;;;;;;; REPORTERS ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

to-report sum-num-jobs-available
  report sum [num-jobs-available] of employers
end 

to-report total-successful-job-changes
  report successful-job-changes
end 

to-report total-successful-negotiations
  report successful-negotiations
end 

to-report avg-salary-job-changers
  report mean [salary] of employees with [tendency = "change"]
end 

to-report avg-salary-non-job-changers
  report mean [salary] of employees with [tendency = "stay"]
end 

to-report total-job-changers
  report count employees with [tenure < 5]
end 

to-report total-non-job-changers
  report count employees with [tenure >= 5]
end