Child of Helping_vs_Harming
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;;; originally all the globals were able to be set by the user; too many damn parameters! ;;; Now they are set in setup; the indicated settings provide some nice behavior globals [ number-of-turtles social-radius exile-distance social-gain life-expectancy ] turtles-own [ ;;; internal setting variables social-currency p-theft p-protect age my-life-expectancy ;;; color variables r g b ;;; turn variables take-action my-neighbors got-away? ;; reproduction variables can-breed? my-mateworthy-neighbors my-mate ;;; helper variables random-choice-num ;;; every turn a turtle uses random to pick what to do; this is so we can pick one random number per turn in the ifelse block my-count ;; this is just a placeholder variable; not at all necessary for logic but is handy to avoid retyping code bloacks ] to setup ca if (verbose? and protect-threshold <= theft-threshold) [ ;;; verbose is just there to be able to turn this message off for behavior-space experiments user-message "Oops: the protection threshold must be larger than the theft threshold" stop ] ;;; set globals to some nice defaults set number-of-turtles 150 ;;; This mostly affects how fast things change; doesnt majorly affect the outcome of the model set social-radius 8 ;;; if this is smaller turtles tend to die out quickly set exile-distance 8 set life-expectancy 50 ;;; much less than 50 and turtles die out before reproducing; much more and everything just slows down. Might as well specify. set social-gain 10 ;;; NOTE: in a different model, social-gain would be a crucial parameter to vary! ;;; However, in this model it doesn't make things that interesting, just move faster. ;;; I think this is because this model is set up such that it's a constant increment, that is, turtles only ever gain or lose ;;; a maximum of social-gain divided amongst neighbors, rather than from each neighbor. Also, social-currency is not a zero sum game ;;; (since turtles are born with social-currency). I thought it made sense to hide it from the user for simplicity ask patches [ set pcolor grey ] ;;; turtles are initialized black and can end up white, so grey background is best crt number-of-turtles [ ;;; initialize color and location. we are going to do some color math so we have to do this a little hamfistedly set r 0 set g 0 set b 0 set color rgb r g b ;; everyone starts off green, randomly placed in the world, with equal social currency set size 2 setxy random-xcor random-ycor ;; internal variables set can-breed? (social-currency > mate-threshold) set social-currency initial-social-currency set p-theft (theft-threshold - 5 + random 11) ;; everyone has their own theft threshold within 5 of the set threshold set p-protect (protect-threshold - 5 + random 11) ;; ditto protection threshold if p-theft >= p-protect [set p-theft (p-protect - 1)] ;; make sure p-theft < p-protect; this gives preference to protection rather than theft. call me old-fashioned. set age 0 set my-life-expectancy (life-expectancy - 5 + random 11) set got-away? false ] reset-ticks end to go if (count turtles = 0) [stop] if stop-at-5000-turtles-or-1000-ticks? ;; do we want the model to eventually halt? [ if (count turtles > 5000 or ticks > 1000) [stop]] ;;; these population/tick limits were decided upon basically by seeing where the model starts to slow down enormously and by which point clear trends have emerged. ;;; first code block resets internals, moves the turtles, and picks what to do ask turtles [ turn-reset ;;; move ifelse any? my-neighbors [ face max-one-of my-neighbors [social-currency]] ;; face your most popular neighbor [ rt random 360 ] ;; or wiggle if you have no neighbors fd 1 ;; take a step towards them ;;; pick an action. Actions will actually happen during the resolution phase ;;; this does NOT have to happen after all the turtles have moved because they are just picking what ;;; they WILL do, they are not actually doing it yet set random-choice-num random 100 ifelse (random-choice-num < p-theft) [ set take-action "steal" ifelse (random 100 < probability-of-getting-away) ;; if you steal, figure out whether you get away with it (independent of who's watching) [ set got-away? true] [ set got-away? false]] [ ifelse (random-choice-num < p-protect) ;; if we got here that means p-theft < choice-num < p-protect [ set take-action "do-nothing" ] ;; and we do nothing [ set take-action "protect" ]] ] ;; otherwise we protect ;;; resolve performs the actions and resolves the consequences ;;; has to happen after all turtles have moved and chosen their actions ask turtles [resolve] ;; within resolve, functions to actually perform actions are called ask turtles [ if (social-currency > 100) [ set social-currency 100 ] if (social-currency <= 0) [ die ] ;; turtles at zero die if (age > my-life-expectancy) [ die ] set age (age + 1) ] ask turtles [ if can-breed? [ reproduce-if-possible ]] ;;; after all actions are resolved, turtles reproduce if they can tick end to turn-reset ;;; reset some information at each tick set my-mate false ;; reset mate info set got-away? false set color rgb r g b ;;; reset color set can-breed? (social-currency > mate-threshold) ;;; reset breeding status set my-neighbors other turtles in-radius social-radius ;; figure out who your neighbors are if (social-currency <= 0) [ die ] ;; turtles at zero die if (age > my-life-expectancy) [ die ] end to resolve ;;; this is only its own function out of convenience; could be in-line with go ifelse (take-action = "steal") [ steal ] [ ifelse (take-action = "protect") [ protect ] [ do-nothing ] ] end to steal ;;; note that steal actually handles MOST of what happens to turtles, i.e., both thieves and protectors ;;; in this implementation, a successful thief takes TOTAL social-gain divided amongst the victims. another possibility would be to have it take a social-gain from EACH victim ifelse (got-away? or not any? my-neighbors with [take-action = "protect"]) ;; if no one is watching out for thieves or you get away with it [ set my-count (count my-neighbors) if (my-count > 0) ;; provided you have neighbors [ set social-currency (social-currency + social-gain) ;; get social-gain from chumpy neighbors ask my-neighbors [set social-currency (social-currency - (social-gain / [my-count] of myself))] ];; each neighbor loses social-gain/count neighbors ;;; if you have no neighbors, don't sweat it, you do nothing. ] ;;; otherwise, someone is watching out for thieves AND you got caught [ set my-count (count my-neighbors with [take-action = "protect"]) set social-currency (social-currency - social-gain) ;; lose social-gain ask my-neighbors with [take-action = "protect"] [ set social-currency (social-currency + (social-gain / [my-count] of myself))] ;;; protectors don't each get social-gain, since the more protectors you have, the less each protection matters ;;; and deal with the consequences of getting caught rt random 360 fd exile-distance ;;; if you get caught stealing, turn and walk away ] ifelse (r < 230) ;;; thieves turn redder [ set r (r + 25) ] [ set r 255 ] end to protect set my-count (count my-neighbors with [take-action = "steal" and not got-away?]) if (my-count = 0) ;; if none of your neighbors tried to steal and did not get away with it, then you are being a busybody [ set social-currency (social-currency - social-gain) ;; lose social-gain ask my-neighbors [set social-currency (social-currency + (social-gain / [count my-neighbors] of myself))]] ;;; all your neighbors are smugly satisfied with themselves and each other ;;; otherwise, someone has tried to steal ;;; but we don't have to do anything because it is handled by the steal function ;;; protectors turn bluer ifelse (b < 230) ;;; turtles who are protectors turn bluer [ set b (b + 25) ] [ set b 255 ] end to do-nothing ;;; the only thing we need to do within this function is change the color a bit ifelse (g < 230) ;;; show the turtle's guilt by turning it redder [ set g (g + 25) ] [ set g 255 ] end to reproduce-if-possible ;; only called with turtles who can reproduce set my-mateworthy-neighbors my-neighbors with [can-breed? and (my-mate = false)] ;; my-mate is set to false at the beginning of each tick if any? my-mateworthy-neighbors [ set my-mate max-one-of my-mateworthy-neighbors [social-currency] ask my-mate [ set my-mate true ] ;;; I know it's a bit odd to have the my-mate variable be a combination of booleans and agents, but this should still work; the point is to have my-mate bound or not ;; we do it this way so that turtles don't mate twice per turn hatch 1 [ set social-currency initial-social-currency set p-protect ((([p-protect] of myself + [p-protect] of [my-mate] of myself) / 2) - 5 + random 11) ;; average p-protect of parents, plus some randomness set p-theft ((([p-theft] of myself + [p-theft] of [my-mate] of myself) / 2) - 5 + random 11) ;; average p-theft of parents, plus some randomness if p-theft >= p-protect [set p-theft (p-protect - 1)] ;; make sure p-theft < p-protect; this gives preference to protection rather than theft. call me old-fashioned. set age 0 set my-life-expectancy ((([my-life-expectancy] of myself + [my-life-expectancy] of [my-mate] of myself) / 2) - 5 + random 11) set got-away? false ;;; placement and color set r 0 set g 0 set b 0 set color rgb r g b ;; no matter who your parents are, you start off innocent rt random 360 fd (exile-distance / 2) ] ] end ;;; reporters for charts to-report num-turtles-that-can-breed ifelse (count turtles = 0) [report 0] [ report count turtles with [can-breed?]] end to-report proportion-of-thieving-turtles ifelse (count turtles = 0) [report 0] [ report count turtles with [r > 250] / count turtles] end to-report proportion-of-protector-turtles ifelse (count turtles = 0) [report 0] [ report count turtles with [b > 250] / count turtles] end to-report proportion-of-placid-turtles ifelse (count turtles = 0) [report 0] [ report count turtles with [g > 250] / count turtles] end to-report proportion-of-mixed-turtles ifelse (count turtles = 0) [report 0] [ report count turtles with [(r > 250) and (b > 250)] / count turtles] end to-report proportion-turtles-who-just-stole ifelse (count turtles = 0) [report 0] [ report turtles-who-just-stole / count turtles] end to-report proportion-turtles-who-just-protected ifelse (count turtles = 0) [report 0] [ report turtles-who-just-protected / count turtles] end to-report proportion-turtles-who-just-did-nothing ifelse (count turtles = 0) [report 0] [ report turtles-who-just-did-nothing / count turtles] end to-report turtles-who-just-stole report count turtles with [take-action = "steal"] end to-report turtles-who-just-protected report count turtles with [take-action = "protect"] end to-report turtles-who-just-did-nothing report count turtles with [take-action = "do-nothing"] end to-report proportion-breeding-turtles ifelse (count turtles with [can-breed?] = 0) [report 0] [report ((count turtles with [can-breed?]) / count turtles)] end to-report proportion-thieving-breeders ifelse (count turtles with [can-breed?] = 0) [report 0] [report ((count turtles with [can-breed? and (take-action = "steal")]) / (count turtles with [can-breed?]))] end to-report proportion-protecting-breeders ifelse (count turtles with [can-breed?] = 0) [report 0] [report ((count turtles with [can-breed? and (take-action = "protect")]) / (count turtles with [can-breed?]))] end to-report proportion-complacent-breeders ifelse (count turtles with [can-breed?] = 0) [report 0] [report ((count turtles with [can-breed? and (take-action = "do-nothing")]) / (count turtles with [can-breed?]))] end
There is only one version of this model, created over 9 years ago by Joe Blass.
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