Price, Personality and Market Equilibrium

turtles-own [
personality ;Type of personality including momentum & contrarian
stock-a-list ; It gets 1 one I buy it and 0 when I sell it.
]

globals [
stock-a-price-vector
selected-stock-a-price-vector
mean-of-price-vector
mean-of-selected-price-vector
initial-stock-holders
]

to setup
ca
   random-seed Experiment-seed

   ask patches [set pcolor white ]

   create-turtles number-of-traders [ ; number-of-persons is set by a slider
      setxy random-xcor random-ycor
      set shape "person"
      personalities-distribution  ;; momentum & contrarian
      set stock-a-list [0]        ; having no stock
      set color red               ; those who have not stock are red
                                    ]

   ask n-of ((percent-of-stock-a-holder / 100) * count turtles)  turtles [   ; percent-of-stock-a-holder is set by a slider
      set stock-a-list [1]        ; having stock
      set color blue              ; those who have  stock are blue
                                   ]

   set stock-a-price-vector (list Price-of-stock-a) ; Price-of-stock-a is set by an input box

   set initial-stock-holders count turtles with [ sum stock-a-list > 0 ]
reset-ticks
end 

to go

   If ticks = time-period [stop] ;; Time period is set by an input box

  ask turtles [ personalities-distribution ] ; type of personalities (momentum or contrarian) are set here by slider

   stock-a-price-updata

   if is-evaluation-period-completed?  [
   set mean-of-selected-price-vector (mean selected-stock-a-price-vector );;;;; take the mean of vector
   ask turtles [if mean-of-selected-price-vector = indicator [ifelse random-float 1 > 0.5 [sell-stock ] [buy-stock]] ]  ;;;;;; No change in stock price
   ask turtles [ if  mean-of-selected-price-vector > indicator [act-based-on-increase]  ]                               ;;;;;;; increase of stock price
   ask turtles [if mean-of-selected-price-vector <  indicator [act-based-on-decrease]  ]                                ;;;;;;; decrease of stock price
   ]

   ask turtles [ color-updating rt random 90 lt random 90 fd random-float 1]
tick
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Helper procedures


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;Setup & go procedure

to personalities-distribution
 ifelse (random-float 1 <= percent-of-momentum-personality) [set personality "MOMENTUM" ][set personality "CONTRARIAN"] ; percent-of-momentum-strategist is set by a slider
end 

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;Go procedures

to stock-a-price-updata

set stock-a-price-vector (lput Price-of-stock-a stock-a-price-vector )   ;;; Updates the vector based on current price data
set mean-of-price-vector mean(stock-a-price-vector) ;;;; Mean of price vector
set selected-stock-a-price-vector stock-a-price-vector  ;;;; save the vector in a selected vector
end 

to-report is-evaluation-period-completed?

 while [length selected-stock-a-price-vector  > evaluation-period-length ] [
 set selected-stock-a-price-vector remove-item 0 selected-stock-a-price-vector         ;;; when the vector exceeds the evaluation period length, it trims it.
  ]
report length selected-stock-a-price-vector  = evaluation-period-length
end 

to-report indicator
 report item 0 selected-stock-a-price-vector   ;; the first element of vector used for comapring with the mean.
end 

to act-based-on-increase
  ifelse personality = "MOMENTUM" [buy-stock] [sell-stock]
end 

to act-based-on-decrease
   ifelse personality = "MOMENTUM" [sell-stock] [buy-stock]
end 

to sell-stock
if sum stock-a-list > 0 [
set stock-a-list lput -1 stock-a-list
ask one-of other turtles [set stock-a-list lput 1 stock-a-list  ]
                       ]
end 

to buy-stock
set stock-a-list lput 1 stock-a-list
ask one-of other turtles with [sum stock-a-list > 0] [set stock-a-list lput -1 stock-a-list]
end 

to color-updating
  ifelse sum stock-a-list > 0 [set color blue ] [ set color red]
end