breed [sellers seller] ;sellers represent the supply side of the economy breed [buyers buyer] ;buyers represent the demand side of the economy breed [IntelligentSellers IntelligentSeller] ;this the only seller that is able to learn in this model breed [MarketOperators MarketOperator] ;as the traders in the economy declare their reservation value, the market operator determines the clearing price in that iteration breed [Actions Action] ;they are the set of actions the intelligent seller can choose from directed-link-breed [opinions opinion] ;they permit to link the intelligent seller to the actions. globals [SellersList ;it is a list with all the reservation values of the sellers, including the intelligent seller. It helps to the market operator to determine the clearing price BuyersList ;it is a list with all the reservation values of the buyers. It helps to the market operator to determine the clearing price EntireList1 ;it is a list that results from the combination of BuyersList and SellersList. It helps to the market operator to determine the clearing price EntireList2 ;it is a list that results from the EntireList1. It helps to the market operator to determine the clearing price ClearingPrice ;it is the clearing price determined from the market operator. Offer10 ;it determines how many times the action with reservation value 10 is chosen from the intelligent seller. Offer40 ;it determines how many times the action with reservation value 20 is chosen from the intelligent seller. Offer50 ;it determines how many times the action with reservation value 30 is chosen from the intelligent seller. Offer60 ;it determines how many times the action with reservation value 40 is chosen from the intelligent seller. ] sellers-own [ReservationValue ;reservation value of the sellers, excluding the intelligent seller. Profit] ;profit of the sellers, it is equal to the clearing price minus the reservation value buyers-own [ReservationValue ;reservation value of the buyers, excluding the intelligent seller. Profit] ;reservation value of the buyers, excluding the intelligent seller. IntelligentSellers-own [ReservationValue ;reservation value of the intelligent seller CurrentOffer ;it is the value of the current reservation value. It is chosen according to the chosen action Profit] ;it is the profit of the intelligent seller. it is equal to the clearing price minus the reservation value Actions-own [ReservationValue] ;every action has an reservation value attached to it opinions-own [Propensity ;every opinion to an action has a propensity that affects the probability of every action to be chosen. Probability] ;every opinion to an action has a probability of being chosen. to setup ca SetupActions SetupTraders SetupSellersList SetupBuyersList CreateInitialDemandSupply SetupOffersHistogram end to SetupActions foreach [10 40 50 60] [create-ordered-Actions 1 [set label ? setxy 7 3 set shape "dot" ] ] ask Actions with [label = 10] [rt 180 fd 0 set ReservationValue 10] ;just to place the Actions in the NetLogo World. They are at the right of it and are gray dots ask Actions with [label = 40] [rt 180 fd 2 set ReservationValue 40] ask Actions with [label = 50] [rt 180 fd 4 set ReservationValue 50] ask Actions with [label = 60] [rt 180 fd 6 set ReservationValue 60] end to SetupTraders ;we setup sellers, buyers and the market operator foreach [10 20 30 40 50] [create-ordered-sellers 1 [set label ? ;create sellers set shape "circle" setxy 2 2 set color blue ] ] ask sellers with [label = 10] [rt 180 fd 0 set ReservationValue 10] ;just to place the sellers in the world. They are the blue circles with their reservation values as labels. ask sellers with [label = 20] [rt 180 fd 1 set ReservationValue 20] ask sellers with [label = 30] [rt 180 fd 3 set ReservationValue 30] ask sellers with [label = 40] [rt 180 fd 4 set ReservationValue 40] ask sellers with [label = 50] [rt 180 fd 5 set ReservationValue 50] foreach [10 20 30 40 50 60] [create-ordered-buyers 1 [set label ? ;create buyers set shape "square" setxy -2 3 set color red ] ] ask buyers with [label = 10] [rt 180 fd 0 set ReservationValue 10] ;just to place the sellers in the world. They are the red circles with their reservation values as labels. ask buyers with [label = 20] [rt 180 fd 1 set ReservationValue 20] ask buyers with [label = 30] [rt 180 fd 2 set ReservationValue 30] ask buyers with [label = 40] [rt 180 fd 4 set ReservationValue 40] ask buyers with [label = 50] [rt 180 fd 5 set ReservationValue 50] ask buyers with [label = 60] [rt 180 fd 6 set ReservationValue 60] set-default-shape MarketOperators "pentagon" ask patches with [pxcor = 0 and pycor = 0] [sprout-MarketOperators 1] ;create Market Operator. It is in the middle of world with the current clearing price as label. ask MarketOperators [set color green set size 2 ] create-IntelligentSellers 1 [setxy 2 3 ;create the intelligent seller. It is the agent represented as a fox face. set shape "wolf face" set color orange create-opinions-to Actions [set label [who] of other-end ;create the opinions to every action set Propensity InitialPropensity ] ask opinions [set Probability (exp(Propensity / CoolingParameter) / sum [exp(Propensity / CoolingParameter)] of [opinions] of myself)] set CurrentOffer one-of Actions with [who = 0] set label [label] of CurrentOffer set ReservationValue [ReservationValue] of CurrentOffer ] end to SetupSellersList set SellersList [ReservationValue] of Sellers set SellersList sentence [ReservationValue] of Sellers [ReservationValue] of IntelligentSellers set SellersList sort SellersList end to SetupBuyersList set BuyersList [ReservationValue] of buyers set BuyersList sort-by [?1 > ?2] BuyersList end to CreateInitialDemandSupply ;draws the initial demand and supply curves set-current-plot "Demand-Supply" set-current-plot-pen "Demand" foreach sort-by [ [ReservationValue] of ?1 > [ReservationValue] of ?2 ] buyers [ plot [ReservationValue] of ? ] set-current-plot-pen "Supply" foreach SellersList [plot ?] end to SetupOffersHistogram ;initializes the histogram that counts how much every action is chosen set-current-plot "Offers Histogram" set-plot-y-range 0 Runs end to go DetermineClearingPrice DetermineProfits LearningActivities tick DoPlot UpdateTraders end to DetermineClearingPrice set SellersList [ReservationValue] of Sellers ; it sets a list of the reservation values. It looks like [10 20 30 40 50] set SellersList sentence [ReservationValue] of Sellers [ReservationValue] of IntelligentSellers ;it includes in the above initiated list the reservation value of the intelligent seller. It looks like [x 10 20 30 40 50] set SellersList sort SellersList ;it sorts the sellerlist from low to high values. It looks like [10 10 20 30 40 50 60] set BuyersList [ReservationValue] of buyers ;it sets the list of the reservation values of the buyers. It looks like [10 20 30 40 50 60] set BuyersList sort-by [?1 > ?2] BuyersList ;it sorts the buyerr list from hight to low values [60 50 40 30 20 10] set EntireList1(map [?1 - ?2] BuyersList SellersList) ;it is a list with the difference between BuyerList and SellerList. It looks like, [(60 - 10) (50 - 10)(40 - 20)(30 - 30)(20 - 40)(10 - 50)] ;[50 40 20 0 -20 -40] set EntireList2 map [? * ?] EntireList1 ;we square every item of the EntireList1 and get something like this [2500 1600 200 0 200 1600] let item0 item 0 EntireList2 ;every item in EntireList2 we give a name. let item1 item 1 EntireList2 let item2 item 2 EntireList2 let item3 item 3 EntireList2 let item4 item 4 EntireList2 let item5 item 5 EntireList2 let KeyItem1 0 ;considering the EntireList2, we choose a KeyItem that it will be the one with value 0. let KeyItem2 0 ;it can be the case that we have two items with value 0. ;the idea is that where the item equals 0 in the EntireLis2, it is where the demand and supply curves cross. ;as already mentioned above, it can be the case that we have two values 0 in the list. That is, because the values that Pentapalli considers ;we can get a list like [x x 0 x x]. The next decision tree identifies those items with reservation value 0. When it finds it or them, ;it gives the position of it or them. Then, in order to find the clearing price, the position of the items with value 0 in the EntireList2 ;will tell the position of the clearing price in the SellersList. ifelse item0 < item1 [] [if item1 = 0 [set KeyItem1 1] ifelse item0 = item1 [set KeyItem1 0 set KeyItem2 1] [ifelse item1 < item2 [] [if item2 = 0 [set KeyItem1 2] ifelse item1 = item2 [set KeyItem1 1 set KeyItem2 2] [ifelse item2 < item3 [] [if item3 = 0 [set KeyItem1 3] ifelse item2 = item3 [set KeyItem1 2 set KeyItem2 3] [ifelse item3 < item4 [] [if item4 = 0 [set KeyItem1 4] ifelse item3 = item4 [set KeyItem1 3 set KeyItem2 4] [ifelse item4 < item5 [] [if item5 = 0 [set KeyItem1 5] ifelse item4 = item5 [set KeyItem1 4 set KeyItem2 5] [set KeyItem1 5] ] ] ] ] ] ] ] ] ] ifelse KeyItem2 = 0 [set ClearingPrice item KeyItem1 SellersList] ;if there is just one item with value 0 in the EntireList2, KeyItem1 shows us which item in the SellerList to choose [set ClearingPrice ((item KeyItem2 SellersList + item KeyItem1 SellersList) / 2)] ;if there are two items with value 0 in the EntireList2, KeyItem1 and KeyItem2 determines which ;numbers in the SellerList are going to be summed and divided by 2 in order to get the clearing price ask MarketOperators [set label ClearingPrice] end to DetermineProfits ask Sellers [set Profit ClearingPrice - ReservationValue ] ask IntelligentSellers [set Profit ClearingPrice - ReservationValue ] end to LearningActivities ;according the chooser, we choose the learning algorithm to be used. if Algorithm = "Roth-Erev RL Algorithm" [UpdateOpinions1] if Algorithm = "Modified Roth-Erev" [UpdateOpinions2] if Algorithm = "Variant Roth-Erev RL Algorithm" [UpdateOpinions3] ChooseNewCurrentOffer end to UpdateOpinions1 ;propensities and probabilities are updated according to the Roth-Erev RL Algorithm ask IntelligentSellers [ if CurrentOffer = Action 0 [set Offer10 Offer10 + 1 ask my-out-opinions with [label = 0] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 0] [set Propensity ((1 - RecencyParameter) * Propensity) + ([Profit] of myself * (ExperimentationParameter / 3)) ] ask my-out-opinions [set Probability (Propensity) / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 1 [set Offer40 Offer40 + 1 ask my-out-opinions with [label = 1] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 1] [set Propensity ((1 - RecencyParameter) * Propensity) + ([Profit] of myself * (ExperimentationParameter / 3)) ] ask my-out-opinions [set Probability (Propensity) / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 2 [set Offer50 Offer50 + 1 ask my-out-opinions with [label = 2] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 2] [set Propensity ((1 - RecencyParameter) * Propensity) + ([Profit] of myself * (ExperimentationParameter / 3)) ] ask my-out-opinions [set Probability (Propensity) / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 3 [set Offer60 Offer60 + 1 ask my-out-opinions with [label = 3] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 3] [set Propensity ((1 - RecencyParameter) * Propensity) + ([Profit] of myself * (ExperimentationParameter / 3)) ] ask my-out-opinions [set Probability (Propensity) / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] ] end to UpdateOpinions2 ;propensities and probabilities are updated according to the Modified Roth-Erev Algorithm ask IntelligentSellers [ if CurrentOffer = Action 0 [set Offer10 Offer10 + 1 ask my-out-opinions with [label = 0] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 0] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability Propensity / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 1 [set Offer40 Offer40 + 1 ask my-out-opinions with [label = 1] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 1] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability Propensity / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 2 [set Offer50 Offer50 + 1 ask my-out-opinions with [label = 2] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 2] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability Propensity / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] if CurrentOffer = Action 3 [set Offer60 Offer60 + 1 ask my-out-opinions with [label = 3] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 3] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability Propensity / (sum [Propensity] of [opinions] of myself) if Probability > 1 [set Probability 1] if Probability < 0 [set Probability 0] ] ] ] end to UpdateOpinions3 ;;propensities and probabilities are updated according to the Variant Roth-Erev Algorithm ask IntelligentSellers [ if CurrentOffer = Action 0 [set Offer10 Offer10 + 1 ask my-out-opinions with [label = 0] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 0] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability (exp(Propensity / CoolingParameter)) / (sum [exp(Propensity / CoolingParameter)] of [opinions] of myself)] ] if CurrentOffer = Action 1 [set Offer40 Offer40 + 1 ask my-out-opinions with [label = 1] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 1] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability (exp(Propensity / CoolingParameter)) / (sum [exp(Propensity / CoolingParameter)] of [opinions] of myself)] ] if CurrentOffer = Action 2 [set Offer50 Offer50 + 1 ask my-out-opinions with [label = 2] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 2] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability (exp(Propensity / CoolingParameter)) / (sum [exp(Propensity / CoolingParameter)] of [opinions] of myself)] ] if CurrentOffer = Action 3 [set Offer60 Offer60 + 1 ask my-out-opinions with [label = 3] [set Propensity ((1 - RecencyParameter) * Propensity) + ((1 - ExperimentationParameter) * [Profit] of myself) ] ask my-out-opinions with [label != 3] [set Propensity ((1 - RecencyParameter) * Propensity) + (ExperimentationParameter * (Propensity / 3)) ] ask my-out-opinions [set Probability (exp(Propensity / CoolingParameter)) / (sum [exp(Propensity / CoolingParameter)] of [opinions] of myself)] ] ] end to ChooseNewCurrentOffer ;it helps to choose the Prevaling Opinion in each iteration. Given that probabilities are not equal, we make use of the Lottery Example that can be ;found in the NetLogo Library. if [label] of PrevailingOpinion = 0 [ask IntelligentSellers [set CurrentOffer Action 0]] if [label] of PrevailingOpinion = 1 [ask IntelligentSellers [set CurrentOffer Action 1]] if [label] of PrevailingOpinion = 2 [ask IntelligentSellers [set CurrentOffer Action 2]] if [label] of PrevailingOpinion = 3 [ask IntelligentSellers [set CurrentOffer Action 3]] end to-report PrevailingOpinion let pick random-float 1 let winner nobody ask opinions [;; if there's no winner yet... while [winner = nobody and probability > 0.000001 ] [ifelse probability > pick [set winner self ] [set pick pick - probability] ] ] report winner end to Update UpdateTraders end to UpdateTraders ask sellers [set Profit 0] ask IntelligentSellers [set Profit 0 if [label] of CurrentOffer = 10 [set ReservationValue 10 set label 10 ] if [label] of CurrentOffer = 40 [set ReservationValue 40 set label 40 ] if [label] of CurrentOffer = 50 [set ReservationValue 50 set label 50 ] if [label] of CurrentOffer = 60 [set ReservationValue 60 set label 60 ] ] ask MarketOperators [set label ClearingPrice] end to UpdateLists set SellersList [ReservationValue] of Sellers set SellersList sentence [ReservationValue] of Sellers [ReservationValue] of IntelligentSellers set SellersList sort SellersList set BuyersList [ReservationValue] of buyers set BuyersList sort-by [?1 > ?2] BuyersList end to DoPlot PlotDemandSupply PlotProfit PlotPropensities PlotProbabilities UpdateOffersHistogram end to PlotDemandSupply set-current-plot "Demand-Supply" clear-plot set-current-plot-pen "Demand" foreach sort-by [[ReservationValue] of ?1 > [ReservationValue] of ?2 ] buyers [plot [ReservationValue] of ? ] set-current-plot-pen "Supply" foreach SellersList [plot ?] end to PlotProfit set-current-plot "Profits" set-current-plot-pen "IntelligentSeller" ask IntelligentSellers [plot Profit] end to PlotPropensities set-current-plot "Propensities" set-current-plot-pen "10" ask opinions with [label = 0] [plot Propensity] set-current-plot-pen "40" ask opinions with [label = 1] [plot Propensity] set-current-plot-pen "50" ask opinions with [label = 2] [plot Propensity] set-current-plot-pen "60" ask opinions with [label = 3] [plot Propensity] end to PlotProbabilities set-current-plot "Probabilities" set-current-plot-pen "10" ask opinions with [label = 0] [plot Probability] set-current-plot-pen "40" ask opinions with [label = 1] [plot Probability] set-current-plot-pen "50" ask opinions with [label = 2] [plot Probability] set-current-plot-pen "60" ask opinions with [label = 3] [plot Probability] end to UpdateOffersHistogram set-current-plot "Offers Histogram" plot-pen-reset set-plot-pen-color 10 ask IntelligentSellers [plot Offer10] set-plot-pen-color 40 ask IntelligentSellers [plot Offer40] set-plot-pen-color 50 ask IntelligentSellers [plot Offer50] set-plot-pen-color 60 ask IntelligentSellers [plot Offer60] end @#$#@#$#@ GRAPHICS-WINDOW 255 10 535 167 7 3 18.0 1 10 1 1 1 0 0 0 1 -7 7 -3 3 0 0 1 ticks BUTTON 4 10 67 43 NIL setup NIL 1 T OBSERVER NIL NIL NIL NIL SLIDER 77 76 259 109 CoolingParameter CoolingParameter 0 10000 10000 1000 1 NIL HORIZONTAL CHOOSER 21 158 204 203 Algorithm Algorithm "Roth-Erev RL Algorithm" "Modified Roth-Erev" "Variant Roth-Erev RL Algorithm" 2 PLOT 566 10 868 200 Demand-Supply Quantity Price 0.0 6.0 0.0 10.0 true true PENS "Demand" 1.0 0 -13345367 true "Supply" 1.0 0 -2674135 true SLIDER 76 10 254 43 ExperimentationParameter ExperimentationParameter 0 0.1 0.01 0.01 1 NIL HORIZONTAL SLIDER 77 42 257 75 RecencyParameter RecencyParameter 0 0.1 0.01 0.01 1 NIL HORIZONTAL SLIDER 80 113 252 146 InitialPropensity InitialPropensity 0 1000 500 100 1 NIL HORIZONTAL BUTTON 5 43 68 76 Go while [ticks < Runs] [go] NIL 1 T OBSERVER NIL NIL NIL NIL PLOT 372 513 855 720 Profits NIL NIL 0.0 10.0 0.0 10.0 true false PENS "IntelligentSeller" 1.0 2 -955883 true "Seller1" 1.0 0 -7500403 true "Seller2" 1.0 0 -2674135 true "Seller3" 1.0 0 -6459832 true "Seller4" 1.0 0 -1184463 true "Seller5" 1.0 0 -10899396 true PLOT 46 215 571 502 Propensities NIL NIL 0.0 10.0 0.0 10.0 true true PENS "10" 1.0 0 -2674135 true "40" 1.0 0 -5825686 true "50" 1.0 0 -13791810 true "60" 1.0 0 -7500403 true PLOT 628 212 1111 502 Probabilities NIL NIL 0.0 10.0 0.0 0.8 true true PENS "10" 1.0 0 -2674135 true "40" 1.0 0 -5825686 true "50" 1.0 0 -13791810 true "60" 1.0 0 -7500403 true PLOT 934 10 1168 195 Offers Histogram NIL NIL 0.0 4.0 0.0 10.0 true false PENS "10" 1.0 1 -2674135 false "40" 1.0 0 -16777216 true "50" 1.0 0 -16777216 true "60" 1.0 0 -16777216 true SLIDER 220 176 312 209 Runs Runs 1 10000 201 200 1 NIL HORIZONTAL @#$#@#$#@ @#$#@#$#@ default true 0 Polygon -7500403 true true 150 5 40 250 150 205 260 250 airplane true 0 Polygon -7500403 true true 150 0 135 15 120 60 120 105 15 165 15 195 120 180 135 240 105 270 120 285 150 270 180 285 210 270 165 240 180 180 285 195 285 165 180 105 180 60 165 15 arrow true 0 Polygon -7500403 true true 150 0 0 150 105 150 105 293 195 293 195 150 300 150 box false 0 Polygon -7500403 true true 150 285 285 225 285 75 150 135 Polygon -7500403 true true 150 135 15 75 150 15 285 75 Polygon -7500403 true true 15 75 15 225 150 285 150 135 Line -16777216 false 150 285 150 135 Line -16777216 false 150 135 15 75 Line -16777216 false 150 135 285 75 bug true 0 Circle -7500403 true true 96 182 108 Circle -7500403 true true 110 127 80 Circle -7500403 true true 110 75 80 Line -7500403 true 150 100 80 30 Line -7500403 true 150 100 220 30 butterfly true 0 Polygon -7500403 true true 150 165 209 199 225 225 225 255 195 270 165 255 150 240 Polygon -7500403 true true 150 165 89 198 75 225 75 255 105 270 135 255 150 240 Polygon -7500403 true true 139 148 100 105 55 90 25 90 10 105 10 135 25 180 40 195 85 194 139 163 Polygon -7500403 true true 162 150 200 105 245 90 275 90 290 105 290 135 275 180 260 195 215 195 162 165 Polygon -16777216 true false 150 255 135 225 120 150 135 120 150 105 165 120 180 150 165 225 Circle -16777216 true false 135 90 30 Line -16777216 false 150 105 195 60 Line -16777216 false 150 105 105 60 car false 0 Polygon -7500403 true true 300 180 279 164 261 144 240 135 226 132 213 106 203 84 185 63 159 50 135 50 75 60 0 150 0 165 0 225 300 225 300 180 Circle -16777216 true false 180 180 90 Circle -16777216 true false 30 180 90 Polygon -16777216 true false 162 80 132 78 134 135 209 135 194 105 189 96 180 89 Circle -7500403 true true 47 195 58 Circle -7500403 true true 195 195 58 circle false 0 Circle -7500403 true true 0 0 300 circle 2 false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 cow false 0 Polygon -7500403 true true 200 193 197 249 179 249 177 196 166 187 140 189 93 191 78 179 72 211 49 209 48 181 37 149 25 120 25 89 45 72 103 84 179 75 198 76 252 64 272 81 293 103 285 121 255 121 242 118 224 167 Polygon -7500403 true true 73 210 86 251 62 249 48 208 Polygon -7500403 true true 25 114 16 195 9 204 23 213 25 200 39 123 cylinder false 0 Circle -7500403 true true 0 0 300 dot false 0 Circle -7500403 true true 90 90 120 face happy false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 255 90 239 62 213 47 191 67 179 90 203 109 218 150 225 192 218 210 203 227 181 251 194 236 217 212 240 face neutral false 0 Circle -7500403 true true 8 7 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Rectangle -16777216 true false 60 195 240 225 face sad false 0 Circle -7500403 true true 8 8 285 Circle -16777216 true false 60 75 60 Circle -16777216 true false 180 75 60 Polygon -16777216 true false 150 168 90 184 62 210 47 232 67 244 90 220 109 205 150 198 192 205 210 220 227 242 251 229 236 206 212 183 fish false 0 Polygon -1 true false 44 131 21 87 15 86 0 120 15 150 0 180 13 214 20 212 45 166 Polygon -1 true false 135 195 119 235 95 218 76 210 46 204 60 165 Polygon -1 true false 75 45 83 77 71 103 86 114 166 78 135 60 Polygon -7500403 true true 30 136 151 77 226 81 280 119 292 146 292 160 287 170 270 195 195 210 151 212 30 166 Circle -16777216 true false 215 106 30 flag false 0 Rectangle -7500403 true true 60 15 75 300 Polygon -7500403 true true 90 150 270 90 90 30 Line -7500403 true 75 135 90 135 Line -7500403 true 75 45 90 45 flower false 0 Polygon -10899396 true false 135 120 165 165 180 210 180 240 150 300 165 300 195 240 195 195 165 135 Circle -7500403 true true 85 132 38 Circle -7500403 true true 130 147 38 Circle -7500403 true true 192 85 38 Circle -7500403 true true 85 40 38 Circle -7500403 true true 177 40 38 Circle -7500403 true true 177 132 38 Circle -7500403 true true 70 85 38 Circle -7500403 true true 130 25 38 Circle -7500403 true true 96 51 108 Circle -16777216 true false 113 68 74 Polygon -10899396 true false 189 233 219 188 249 173 279 188 234 218 Polygon -10899396 true false 180 255 150 210 105 210 75 240 135 240 house false 0 Rectangle -7500403 true true 45 120 255 285 Rectangle -16777216 true false 120 210 180 285 Polygon -7500403 true true 15 120 150 15 285 120 Line -16777216 false 30 120 270 120 leaf false 0 Polygon -7500403 true true 150 210 135 195 120 210 60 210 30 195 60 180 60 165 15 135 30 120 15 105 40 104 45 90 60 90 90 105 105 120 120 120 105 60 120 60 135 30 150 15 165 30 180 60 195 60 180 120 195 120 210 105 240 90 255 90 263 104 285 105 270 120 285 135 240 165 240 180 270 195 240 210 180 210 165 195 Polygon -7500403 true true 135 195 135 240 120 255 105 255 105 285 135 285 165 240 165 195 line true 0 Line -7500403 true 150 0 150 300 line half true 0 Line -7500403 true 150 0 150 150 pentagon false 0 Polygon -7500403 true true 150 15 15 120 60 285 240 285 285 120 person false 0 Circle -7500403 true true 110 5 80 Polygon -7500403 true true 105 90 120 195 90 285 105 300 135 300 150 225 165 300 195 300 210 285 180 195 195 90 Rectangle -7500403 true true 127 79 172 94 Polygon -7500403 true true 195 90 240 150 225 180 165 105 Polygon -7500403 true true 105 90 60 150 75 180 135 105 plant false 0 Rectangle -7500403 true true 135 90 165 300 Polygon -7500403 true true 135 255 90 210 45 195 75 255 135 285 Polygon -7500403 true true 165 255 210 210 255 195 225 255 165 285 Polygon -7500403 true true 135 180 90 135 45 120 75 180 135 210 Polygon -7500403 true true 165 180 165 210 225 180 255 120 210 135 Polygon -7500403 true true 135 105 90 60 45 45 75 105 135 135 Polygon -7500403 true true 165 105 165 135 225 105 255 45 210 60 Polygon -7500403 true true 135 90 120 45 150 15 180 45 165 90 square false 0 Rectangle -7500403 true true 30 30 270 270 square 2 false 0 Rectangle -7500403 true true 30 30 270 270 Rectangle -16777216 true false 60 60 240 240 star false 0 Polygon -7500403 true true 151 1 185 108 298 108 207 175 242 282 151 216 59 282 94 175 3 108 116 108 target false 0 Circle -7500403 true true 0 0 300 Circle -16777216 true false 30 30 240 Circle -7500403 true true 60 60 180 Circle -16777216 true false 90 90 120 Circle -7500403 true true 120 120 60 tree false 0 Circle -7500403 true true 118 3 94 Rectangle -6459832 true false 120 195 180 300 Circle -7500403 true true 65 21 108 Circle -7500403 true true 116 41 127 Circle -7500403 true true 45 90 120 Circle -7500403 true true 104 74 152 triangle false 0 Polygon -7500403 true true 150 30 15 255 285 255 triangle 2 false 0 Polygon -7500403 true true 150 30 15 255 285 255 Polygon -16777216 true false 151 99 225 223 75 224 truck false 0 Rectangle -7500403 true true 4 45 195 187 Polygon -7500403 true true 296 193 296 150 259 134 244 104 208 104 207 194 Rectangle -1 true false 195 60 195 105 Polygon -16777216 true false 238 112 252 141 219 141 218 112 Circle -16777216 true false 234 174 42 Rectangle -7500403 true true 181 185 214 194 Circle -16777216 true false 144 174 42 Circle -16777216 true false 24 174 42 Circle -7500403 false true 24 174 42 Circle -7500403 false true 144 174 42 Circle -7500403 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