Child of Version_20250927-1_Spread of Opinions Influenced by Group Effects reward metablock plus memes v2
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WHAT IS IT?
This simulator was developed by the Public Opinion Research Group to model how political and social opinions spread, polarize, and evolve within a connected population. It is based on an agent-based model (ABM) where each agent represents an individual characterized by their opinion, prevalence (depth of conviction), influence, and social links.
Agents interact over time through probabilistic influence, producing emergent collective behaviors such as polarization, convergence, or fragmentation.
The model was originally designed to study the Québec electorate, linking voters’ attitudes to their internal representations (memes) underlying support or opposition to political issues.
HOW TO USE IT
- Adjust the population size with the
pop
slider. - Click Setup to initialize agents and their links (background set to black).
- Click Go to start or pause the simulation.
3D Representation
- X-axis → Opinion (−1 to +1)
- Y-axis → Prevalence (0–99)
- Z-axis → Influence (0–1)
Colors:
- Blue → positive/right-leaning opinion
- Red → negative/left-leaning opinion
- Yellow → meta-influencers
- Green links → same sign (agreement)
- Gray links → opposite sign (disagreement)
USER INTERFACE OVERVIEW
1. General Controls
- Setup → initialize agents and reset view.
- Go → start/stop simulation.
- in_file → load saved agent data.
- refresh / cumulative → control graph display.
2. Population and Iteration Parameters
- pop → number of agents.
- nb_try, max_iter, threshold → govern experiment repetitions.
- choice_iter → select iteration to reload saved state.
3. Network Dynamics
Agents form and dissolve links depending on opinion similarity and probabilistic thresholds.
- link-removal-threshold → above this distance, links may break.
- link-formation-threshold → below this distance, new links may form.
- prob → global probability of link change.
- linksdown / linksup → limits number of link changes per tick.
- bridge-prob → probability of creating “bridging” links between opposite camps.
4. Meta-Influencers
Special agents with fixed influence = 1 who can stabilize or polarize the network.
- meta-influencers-selection → choose distribution (All, Left, Right).
- meta-influencers → proportion of meta agents.
- meta-links, meta-min, meta-max → number of links per meta agent.
- meta-ok → enable or disable meta-influencers.
- vary-influence → if ON, influence grows after successful transmission and decreases after failure.
- metablock → if ON, meta-influencers cannot switch opinion polarity (they remain Left or Right).
5. Opinion Dynamics
Key Parameters
- rate-infl → rate of influence adjustment per success.
- modulation-prevalence → toggle prevalence variation with opinion change.
- rate-modulation → rate of prevalence adaptation.
- noise → probability of random opinion drift.
- polarization-factor → reduces adoption probability across distant opinions.
- prevalence-weight → adjusts how much prevalence influences adoption.
- adoption-floor → minimal adoption probability, even with large opinion gaps.
6. Group Impact
Adoption probability is influenced by group alignment.
- group-impact-mode → all (all neighbours) or k-nearest (closest in opinion).
- group-k → number of neighbours considered in k-nearest mode.
- group-impact-weight → strength of group effect.
group-impact-alpha → non-linearity:
<1
→ small minorities have strong influence.=1
→ linear response.>1
→ large majorities dominate influence.
7. Reward Mechanism
Agents gain or lose influence potential depending on success in persuasion.
- reward-step → increment in transmission probability per success.
- reward-cap → maximum bonus that can be accumulated.
- reward-scope → defines which agents are rewarded (both, left-only, right-only).
- reward-prev-delta → increase in the target’s prevalence after adoption.
- reward-decay → gradual reduction of accumulated reward.
8. Meme-Based Cognition
When use-memes? is ON, opinions result from internal stocks of meme-plus and meme-minus, representing arguments “for” and “against”.
- meme-max → maximum meme capacity per agent.
- meme-gain → increase in memes after successful influence.
- meme-anti-leak → erosion rate of opposite meme stock.
- meme-decay → forgetting rate.
Derived variables:
- Opinion = balance between positive and negative memes.
- Prevalence = total memes held by the agent.
9. External Events (Including Repetition)
External shocks simulate real-world influences such as political crises or media waves.
Main Controls
- event → triggers a one-time event.
- auto_event → automates events.
- tick-event → iteration at which next event occurs.
- repeat-event → activates repeated events.
- event-pace → defines interval (in ticks) between repeated events.
- event-prob-max → maximum proportion of affected agents.
- lowmeme / highmeme, low-prev / high-prev → restrict which agents are targeted.
- event_size → magnitude of opinion shift.
- prev_change → change in prevalence after event.
Event Repetition Example
If auto_event
and repeat-event
is ON and event-pace = 10
, the same event reoccurs every 10 iterations.
Combined with event-prob-max, this enables realistic modeling of recurring but partial media shocks.
- 1.0 → global shock (entire population)
- 0.1 → limited audience
- 0.01 → local perturbations only
OUTPUTS
Monitors
- % Left / Right agents
- Median opinion, prevalence, influence
- Number of inversions, links created/removed
- Event frequency
Graph
Tracks evolution of global indicators over time.
CSV Export
If csv-export is ON, simulation results are recorded for each trial.
THINGS TO NOTICE
- Observe polarization and convergence patterns.
- Study how meta-influencers stabilize or destabilize clusters.
- Analyze the role of memetic representation in resilience or volatility.
- Test how repeated external events alter long-term opinion structures.
CREDITS
- Concept: Public Opinion Research Group (GROP)
- Implementation: Pierre-Alain Cotnoir (2015–2025)
- AI-assisted design: GPT-4 / GPT-5 (2024–2025)
- Contact: pacotnoir@gmail.com
Comments and Questions
extensions [sound nw] ;; For using sound and Network package globals [ min-prevalence max-prevalence meta-influencers-droit meta-influencers-gauche iter change total inversion try major fractale ordonnee abcisse profondeur list_data file-in in_data repet_data links-dead links-create meta-agents meta-links meta-create Interactions %Major ;; === CSV export === csv-export csv-basename csv-file csv-open? ;; === Paramètres d’inversion / ponts (sliders UI possibles) === ;;prevalence-weight ;; >= 0 ; amplification du rôle de Δprégnance ;;adoption-floor ;; [0..1] ; plancher minimal pour la pénalité de polarisation ;;bridge-prob ;; [0..1] ; probabilité de créer un lien-pont (opinion éloignée) ;; === Paramètres de RÉCOMPENSE (sliders/inputs UI) === ;;reward-step ;; palier d’augmentation du bonus à chaque succès (ex: 0.05) ;;reward-cap ;; plafond du bonus cumulé (ex: 0.50) ;;reward-scope ;; "both" | "left-only" | "right-only" ;;reward-prev-delta ;; hausse de prégnance du ciblé au succès (ex: 0..5), 0 = off ;;reward-decay ;; décroissance du bonus par tick (ex: 0..0.01), 0 = off ] turtles-own [ opinion ;; [-1, 1] prevalence ;; [min-prevalence, max-prevalence] agent-type ;; "Right side" | "Left side" influence ;; [0, 1] opinion-previous influence-previous x3d y3d z3d ;; Mèmes (stock pro/anti) meme-plus meme-minus ;; variables utilitaires old-opinion proposed-opinion ;; Récompense de transmission (bonus multiplicatif p-adopt côté émetteur) tx-bonus ] ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; SETUP ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to setup clear-all set repet_data false set iter 0 set min-prevalence 0 set max-prevalence 99 set-default-shape turtles "person" set try 1 set major 0 set tick-event 50 set links-dead 0 set links-create 0 set meta-create 0 set meta-agents 0 set change 0 set total 0 set inversion 0 set fractale 0 if vary-influence = true or meta-ok = true [ set meta-links meta-min ] ;; === Defaults CSV === if not is-boolean? csv-export [ set csv-export false ] if (not is-string? csv-basename) or (csv-basename = "") [ set csv-basename "run" ] set csv-open? false ;; === Defaults IMPACT DE GROUPE === if (not is-string? group-impact-mode) [ set group-impact-mode "all" ] ;; "all" | "k-nearest" if (not is-number? group-k) [ set group-k 10 ] if (not is-number? group-impact-weight) [ set group-impact-weight 0.5 ] if (not is-number? group-impact-alpha) [ set group-impact-alpha 1.0 ] ;; === Default switches === if not is-boolean? show-links? [ set show-links? false ] if not is-boolean? metablock [ set metablock false ] ;; === Defaults inversion/ponts === if (not is-number? prevalence-weight) [ set prevalence-weight 1.5 ] if (not is-number? adoption-floor) [ set adoption-floor 0.02 ] if (not is-number? bridge-prob) [ set bridge-prob 0.10 ] ;; === Defaults REWARD === if not is-number? reward-step [ set reward-step 0.05 ] if not is-number? reward-cap [ set reward-cap 0.50 ] if not is-string? reward-scope [ set reward-scope "both" ] if not is-number? reward-prev-delta [ set reward-prev-delta 0 ] if not is-number? reward-decay [ set reward-decay 0 ] ;; === Defaults MEMES === if not is-boolean? use-memes? [ set use-memes? false ] if not is-number? meme-max [ set meme-max 100 ] if not is-number? meme-gain [ set meme-gain 1.0 ] if not is-number? meme-anti-leak [ set meme-anti-leak 0.0 ] if not is-number? meme-decay [ set meme-decay 0.0 ] set-background-black create rapport end to create ;; Right side create-turtles pop / 2 [ set agent-type "Right side" set opinion random-float 1 ;; (0,1) set color blue set prevalence random-float (opinion * 100) set influence random-float 1 set opinion-previous opinion set influence-previous influence set tx-bonus 0 ;; init mèmes cohérente avec (prevalence, opinion) let tot initial-prevalence-to-memes prevalence ifelse opinion >= 0 [ set meme-plus tot * (0.5 + 0.5 * abs opinion) set meme-minus tot - meme-plus ] [ set meme-minus tot * (0.5 + 0.5 * abs opinion) set meme-plus tot - meme-minus ] update-3d self ] ;; Left side create-turtles pop / 2 [ set agent-type "Left side" set opinion (random-float 1 - 1) ;; (-1,0) set color red set prevalence random-float (abs opinion * 100) set influence random-float 1 set opinion-previous opinion set influence-previous influence set tx-bonus 0 ;; init mèmes cohérente avec (prevalence, opinion) let tot initial-prevalence-to-memes prevalence ifelse opinion >= 0 [ set meme-plus tot * (0.5 + 0.5 * abs opinion) set meme-minus tot - meme-plus ] [ set meme-minus tot * (0.5 + 0.5 * abs opinion) set meme-plus tot - meme-minus ] update-3d self ] ;; Méta-influenceurs initiaux influenceurs reset-ticks set total 0 set change 0 set Interactions 0 set %Major 0 update-networks recolor-links apply-link-visibility end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; SORTIES / RAPPORT ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to rapport if output = "Statistics" [ output-print (word "Try ; " "Iter ; " "Opinion global ; " "Opinion right side ; " "Opinion left side ; " "Prevalence right side ; " "Prevalence left side ; " "Influence right side ; " "Influence left side ; " "Left % ; " "Right % ; " "Links-Remove ; " "Links-Create ; " "Inversion % ; " "change ; " "total ; " "fractale") ] if output = "Values" [ output-print (word "Try ; " "Ticks ; " "Agents ; " "Prevalence ; " "Opinion ; " "Influence ; " "meme droit ;" "meme plus ; " "meme minus") ] if output = "File" [ ; ask turtles [ ; let pre prevalence ;let mem opinion ; let infl influence ; let ti ticks output-print (word "ti ; " "pre ;" "mem ; " "infl ; " "agent") ; ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; META-INFLUENCEURS ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to influenceurs ;; All if meta-influencers-selection = "All" [ let k round (count turtles * meta-influencers / 100) if k > 0 [ ask n-of k turtles [ if (prevalence >= prev-low and prevalence <= prev-high) [ set influence 1 set color yellow set meta-agents meta-agents + 1 ] ] ] ] ;; Right side if meta-influencers-selection = "Right side" [ set meta-influencers-droit round (count turtles * meta-influencers / 100) let candidates turtles with [opinion > 0] let k min list meta-influencers-droit count candidates if k > 0 [ ask n-of k candidates [ if (prevalence > prev-low and prevalence <= prev-high) [ set influence 1 set color yellow set meta-agents meta-agents + 1 ] ] ] ] ;; Left side if meta-influencers-selection = "Left side" [ set meta-influencers-gauche round (count turtles * meta-influencers / 100) let candidates turtles with [opinion < 0] let k min list meta-influencers-gauche count candidates if k > 0 [ ask n-of k candidates [ if (prevalence > prev-low and prevalence <= prev-high) [ set influence 1 set color yellow set meta-agents meta-agents + 1 ] ] ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; OUTILS MÉTA / VETO ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Un agent est "méta" s'il est jaune OU si son influence vaut 1 to-report meta? report (color = yellow) or (influence = 1) end ;; Change l'opinion en respectant le veto méta quand metablock = true. ;; Solution 1 (renforcement sans inversion) : ;; - si la nouvelle opinion change le signe d’un méta alors que metablock=ON, ;; on conserve le signe ACTUEL et on prend la magnitude MAX(abs(old), abs(new)). to maybe-set-opinion [ new-op ] let old-op opinion let bounded-op max list -1 min list 1 new-op if metablock and meta? and (sign old-op != sign bounded-op) [ let mag max list (abs old-op) (abs bounded-op) set opinion (sign old-op) * mag stop ] set opinion bounded-op end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; BOUCLE PRINCIPALE ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to go ifelse (iter < max_iter) [ if iter > 0 [ set Interactions (total / iter) ] if iter > 0 [ set %Major (major / iter * 100) ] set iter iter + 1 set meta-create 0 if (iter = 1 and csv-export and not csv-open?) [ csv-begin ] ifelse auto_event = true [ if (tick-event = iter) [event if repeat-event [set tick-event (tick-event + event-pace)]] ] [set tick-event (iter + event-pace)] if meta-ok = true [ meta ] update-opinions if network = true [ update-networks ] recolor-links apply-link-visibility if output = "Statistics" [ let avg-opinion mean [opinion] of turtles let positive-opinion safe-median (turtles with [opinion >= 0]) "opinion" let negative-opinion safe-median (turtles with [opinion < 0]) "opinion" let positive-prevalence (safe-median (turtles with [opinion >= 0]) "prevalence") / 100 let negative-prevalence (safe-median (turtles with [opinion < 0]) "prevalence") / 100 let positive-influence safe-median (turtles with [opinion >= 0]) "influence" let negative-influence safe-median (turtles with [opinion < 0]) "influence" let Left% (count turtles with [opinion < 0]) / (pop / 100) let Right% (count turtles with [opinion >= 0]) / (pop / 100) let ti iter output-print (word try " ; " ti " ; " avg-opinion " ; " positive-opinion " ; " negative-opinion " ; " positive-prevalence " ; " negative-prevalence " ; " positive-influence " ; " negative-influence " ; " Left% " ; " Right% " ; " links-dead " ; " links-Create " ; " inversion " ; " change " ; " total " ; " fractale) ] tick if (change > 1 and total > 1) [ set fractale (ln total) / (ln change) ] if (cumulative = false) [ set change 0 set total 0 ] colorer if (refresh = true) [ if ticks > 200 [ reset-ticks clear-plot ] ] if threshold <= (count turtles with [opinion > 0]) / (pop / 100) [ set major major + 1 ] if csv-export [ csv-row ] ] [ ifelse (try < nb_try) [ if csv-export [ csv-end ] set try try + 1 set major 0 clear-turtles clear-plot set change 0 set total 0 set fractale 0 set meta-links meta-min set iter 0 set tick-event 50 set links-create 0 set links-dead 0 set meta-create 0 set meta-agents 0 set min-prevalence 0 set max-prevalence 99 ifelse (repet_data = true) [ data ] [ create set meta-links meta-min ] ] [ if csv-export [ csv-end ] sound:play-note "Tubular Bells" 60 64 1 stop ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; MISE À JOUR DES OPINIONS (effet de groupe + récompenses + mèmes + veto méta) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to update-opinions ask turtles [ set opinion-previous opinion let target one-of link-neighbors if target != nobody [ ;; Δprégnance (tolérance 1) let raw-dprev ([prevalence] of target) - prevalence if raw-dprev < 1 [ set raw-dprev 0 ] let dprev raw-dprev / max-prevalence if dprev > 0 [ ;; distance mémique en valeur absolue des signes let dmem abs(abs(opinion) - abs([opinion] of target)) ;; base-prob + pénalité de polarisation let base-prob dprev * prevalence-weight let pol-penalty max list adoption-floor (1 - polarization-factor * dmem) ;; probabilité brute (sans groupe), pondérée par influence & tx-bonus de l’émetteur let p-adopt base-prob * pol-penalty * [influence] of target * (1 + [tx-bonus] of target) ;; effet de groupe let sgn-emetteur sign ([opinion] of target) let gprob group-alignment-effective self sgn-emetteur let w group-impact-weight let alpha group-impact-alpha set p-adopt p-adopt * ((1 - w) + (w * (gprob ^ alpha))) ;; borne [0,1] if p-adopt < 0 [ set p-adopt 0 ] if p-adopt > 1 [ set p-adopt 1 ] ;; tirage if random-float 1 < p-adopt [ set old-opinion opinion set proposed-opinion [opinion] of target ifelse use-memes? [ ;; renforcement des mèmes du receveur selon le signe de l’émetteur transmit-memes target ;; opinion & prevalence dérivées des mèmes (protégées par metablock) recompute-from-memes ] [ ;; adoption « historique » protégée par veto maybe-set-opinion proposed-opinion ] ;; si veto/reflexion n’a pas modifié le signe et que rien n’a changé → pas de reward if opinion = old-opinion [ stop ] ;; succès de transmission set total total + 1 ;; récompense à l’émetteur si éligible let emitter-sign sign ([opinion] of target) let eligible? (reward-scope = "both") or (reward-scope = "left-only" and emitter-sign < 0) or (reward-scope = "right-only" and emitter-sign >= 0) if eligible? [ ask target [ set tx-bonus min (list reward-cap (tx-bonus + reward-step)) ] ] ;; option : hausse de prégnance du ciblé if reward-prev-delta > 0 [ set prevalence min (list max-prevalence (prevalence + reward-prev-delta)) ] ;; dynamique d’influence (logique existante) set influence-previous influence if vary-influence = true [ if abs(old-opinion) > abs(opinion) [ set influence min (list 1 (influence + rate-infl)) if (influence-previous < 1 and influence = 1) [ if meta-ok = true [ if meta-links < meta-max [ set meta-links meta-links + 1 ] set meta-agents meta-agents + 1 ] set color yellow ] ] if abs(old-opinion) < abs(opinion) [ set influence max (list 0 (influence - rate-infl)) if (influence < influence-previous and influence-previous = 1) [ if meta-ok = true [ set meta-agents meta-agents - 1 ifelse opinion >= 0 [ set color blue ] [ set color red ] ] ] ] ] ;; comptage des inversions (si non bloquée par veto/réflexion) if (sign old-opinion) != (sign opinion) [ set change change + 1 ] ] ] ] ;; modulation de la prévalence if modulation-prevalence = true [ if prevalence > abs opinion * 100 [ set prevalence prevalence - abs(opinion - opinion-previous) * influence * Rate-modulation ] if prevalence < abs opinion * 100 [ set prevalence prevalence + abs(opinion - opinion-previous) * influence * Rate-modulation ] if prevalence < min-prevalence [ set prevalence min-prevalence ] if prevalence > max-prevalence [ set prevalence max-prevalence ] ] ;; bruit additif (protégé par veto/réflexion) if random-float 1 < noise [ let delta (random-float 0.4 - 0.2) maybe-set-opinion (opinion + delta) ] ;; décroissance des mèmes éventuelle if use-memes? [ decay-memes ] ;; update 3D update-3d self ;; logging if (output = "Values" or output = "File") [ compute-statistics ] ] ;; décroissance du bonus (optionnelle) if reward-decay > 0 [ ask turtles [ set tx-bonus max (list 0 (tx-bonus - reward-decay)) ] ] ;; inversion % ifelse (total > 0) [ set inversion (100 * change / total) ] [ set inversion 0 ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; COLORATION ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to colorer ask turtles [ ifelse meta? [ set color yellow ] [ ifelse opinion >= 0 [ set color blue ] [ set color red ] ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; MISE À JOUR DU RÉSEAU (suppression/formation + ponts) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to update-networks ;; suppression let doomed links with [ abs([opinion] of end1 - [opinion] of end2) > (link-removal-threshold / 100) ] let doomedProb doomed with [ random-float 1 < prob ] let n-remove min (list linksdown count doomedProb) if n-remove > 0 [ ask n-of n-remove doomedProb [ die ] set links-dead links-dead + n-remove ] ;; formation let j linksup while [j > 0] [ let t one-of turtles if t = nobody [ stop ] ask t [ let myop opinion let candidates other turtles with [ not link-neighbor? myself ] let pool-homo candidates with [ abs(opinion - myop) < (link-formation-threshold / 100) ] let pool-bridge candidates with [ (sign opinion) != (sign myop) ] let friend nobody if any? pool-bridge and (random-float 1 < bridge-prob) [ set friend max-one-of pool-bridge [ abs(opinion - myop) ] ] if (friend = nobody) and any? pool-homo [ set friend min-one-of pool-homo [ abs(opinion - myop) ] ] if friend != nobody and (random-float 1 < prob) [ create-link-with friend set links-create links-create + 1 let same-sign? (sign opinion) = (sign [opinion] of friend) ask link-with friend [ set color (ifelse-value same-sign? [ green ] [ gray ]) set thickness linktick if show-links? [ show-link ] ] ] ] set j j - 1 ] end to meta if not network [ stop ] ask turtles [ let pool other turtles with [ color = yellow and not link-neighbor? myself and (count link-neighbors) < meta-links ] if any? pool [ let friend one-of pool create-link-with friend let same-sign? (sign opinion) = (sign [opinion] of friend) ask link-with friend [ set color (ifelse-value same-sign? [ green ] [ gray ]) set thickness linktick if show-links? [ show-link ] ] ] ] end to apply-link-visibility ifelse show-links? [ ask links [ show-link ] ] [ ask links [ hide-link ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; STATISTIQUES RUNTIME ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to compute-statistics if output = "Values" [ let pre prevalence let mem opinion let infl influence let ag who let ti ticks let ess try let memed (count turtles with [opinion > 0]) / (pop / 100) let maj major let mplus meme-plus let mminus meme-minus output-print (word ess " ; " ti " ; " ag " ; " pre " ; " mem " ; " infl " ; " memed " ; " mplus " ; " mminus) ] if output = "File" [ let pre prevalence let mem opinion let infl influence let ti ticks let ag who output-print (word ti " ; " pre " ; " mem " ; " infl " ; " ag) ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; I/O : LECTURE FICHIER D’AGENTS ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to in_file carefully [ set file-in user-file if (file-in != false) [ set list_data [] file-open file-in while [not file-at-end?] [ set list_data sentence list_data (list (list file-read file-read file-read file-read)) ] file-close user-message "File uploaded!" set in_data true ] ] [ user-message "File read error" ] data end to data clear-turtles clear-links let tick_to_load choice_iter ifelse (is-list? list_data) [ let filtered_data filter [ row -> first row = tick_to_load ] list_data create-turtles length filtered_data [ let my_index who let agent_data item my_index filtered_data set prevalence item 1 agent_data set opinion item 2 agent_data set influence item 3 agent_data if influence = 1 [ set meta-agents meta-agents + influence ] set opinion-previous opinion set influence-previous influence set tx-bonus 0 if opinion < 0 [ set color red set agent-type "Left side" ] if opinion > 0 [ set color blue set agent-type "Right side" ] if influence = 1 [ set color yellow ] ;; init mèmes en cohérence let tot initial-prevalence-to-memes prevalence ifelse opinion >= 0 [ set meme-plus tot * (0.5 + 0.5 * abs opinion) set meme-minus tot - meme-plus ] [ set meme-minus tot * (0.5 + 0.5 * abs opinion) set meme-plus tot - meme-minus ] update-3d self ] ;influenceurs ] [ set in_data false user-message "Read error" ] update-networks apply-link-visibility recolor-links influenceurs update-opinions set repet_data true end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ÉVÉNEMENT EXTERNE (protégé par veto/réflexion) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to event ask turtles [ let event-prob random-float 1 ;; (0,1) if event-prob <= event-prob-max [ ifelse meme_set = true [ if (to_left = false) [ if agent-type = "Right side" [ if opinion < 0 [ maybe-set-opinion (opinion + event_size) ] ] ] if (to_left = true) [ if agent-type = "Left side" [ if opinion > 0 [ maybe-set-opinion (opinion - event_size) ] ] ] ] [ if (to_left = false) [ if (opinion < high_meme and opinion > low_meme and prevalence < high-prev and prevalence > low-prev) [ maybe-set-opinion (opinion + event_size) if (prev_change != 0) [ set prevalence min (list max-prevalence (prevalence + prev_change)) ] ] ] if (to_left = true) [ if (opinion > low_meme and opinion < high_meme and prevalence > low-prev and prevalence < high-prev) [ maybe-set-opinion (opinion - event_size) if (prev_change != 0) [ set prevalence min (list max-prevalence (prevalence + prev_change)) ] ] ] ] ;; init mèmes cohérente avec (prevalence, opinion) if use-memes? [ let tot initial-prevalence-to-memes prevalence ifelse opinion >= 0 [ set meme-plus tot * (0.5 + 0.5 * abs opinion) set meme-minus tot - meme-plus ] [ set meme-minus tot * (0.5 + 0.5 * abs opinion) set meme-plus tot - meme-minus ]] ] ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; UTILITAIRES ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to set-background-black ask patches [ set pcolor black ] end to update-3d [agt] ask agt [ set x3d opinion * 16 set y3d prevalence / 6 set z3d influence * 16 setxyz x3d y3d z3d ] end to-report safe-median [agentset varname] if not any? agentset [ report 0 ] report median [ runresult varname ] of agentset end to-report sign [x] ifelse x > 0 [ report 1 ] [ ifelse x < 0 [ report -1 ] [ report 0 ] ] end to recolor-links ask links [ let s1 sign [opinion] of end1 let s2 sign [opinion] of end2 ifelse s1 = s2 [ set color green ] [ set color gray ] set thickness linktick ] end ;; IMPACT DE GROUPE (tous les voisins liés) to-report group-alignment-all [agt sign-ref] let nbrs [link-neighbors] of agt if not any? nbrs [ report 0.5 ] let same count nbrs with [ (sign opinion) = sign-ref ] report same / count nbrs end ;; IMPACT DE GROUPE (k plus proches) to-report group-alignment-k [agt sign-ref k] let nbrs [link-neighbors] of agt let deg count nbrs if deg = 0 [ report 0.5 ] let kk max list 1 min list deg floor k let agop [opinion] of agt let pool min-n-of kk nbrs [ abs(opinion - agop) ] if not any? pool [ report 0.5 ] let same count pool with [ (sign opinion) = sign-ref ] report same / count pool end ;; Sélecteur de mode to-report group-alignment-effective [agt sign-ref] ifelse (group-impact-mode = "k-nearest") [ report group-alignment-k agt sign-ref group-k ] [ report group-alignment-all agt sign-ref ] end ;; Mapping prevalence -> stock initial de mèmes to-report initial-prevalence-to-memes [prev] report (prev / 99) * meme-max end ;; Recalcule opinion & prevalence à partir des mèmes (protégé par veto/réflexion) to recompute-from-memes let tot meme-plus + meme-minus if tot < 1e-6 [ set tot 1e-6 ] set proposed-opinion ((meme-plus - meme-minus) / tot) maybe-set-opinion proposed-opinion let scaled (tot / meme-max) * 99 if scaled < 0 [ set scaled 0 ] if scaled > 99 [ set scaled 99 ] set prevalence scaled end ;; Décroissance des mèmes to decay-memes if meme-decay <= 0 [ stop ] set meme-plus max list 0 (meme-plus * (1 - meme-decay)) set meme-minus max list 0 (meme-minus * (1 - meme-decay)) end ;; Transmission des mèmes d’un émetteur vers le receveur (self) to transmit-memes [emitter] let sgn sign [opinion] of emitter ifelse sgn >= 0 [ set meme-plus meme-plus + meme-gain set meme-minus max list 0 (meme-minus - meme-anti-leak * meme-gain) ] [ set meme-minus meme-minus + meme-gain set meme-plus max list 0 (meme-plus - meme-anti-leak * meme-gain) ] ;; plafonner en douceur let tot meme-plus + meme-minus if tot > meme-max [ let factor meme-max / tot set meme-plus meme-plus * factor set meme-minus meme-minus * factor ] end ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; EXPORT CSV (par essai) ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; to csv-begin if not csv-export [ stop ] set csv-file (word csv-basename "-" try ".csv") file-close-all if file-exists? csv-file [ file-delete csv-file ] file-open csv-file set csv-open? true file-print "try,iter,tick,left_pct,right_pct,avg_opinion,med_op_right,med_op_left,med_prev_right,med_prev_left,med_infl_right,med_infl_left,links_remove,links_create,inversion_pct,change,total,fractale,major" end to csv-row if not csv-open? [ stop ] let avg-opinion mean [opinion] of turtles let opR safe-median (turtles with [opinion >= 0]) "opinion" let opL safe-median (turtles with [opinion < 0]) "opinion" let prevR (safe-median (turtles with [opinion >= 0]) "prevalence") / 100 let prevL (safe-median (turtles with [opinion < 0]) "prevalence") / 100 let inflR safe-median (turtles with [opinion >= 0]) "influence" let inflL safe-median (turtles with [opinion < 0]) "influence" let leftpct (count turtles with [opinion < 0]) / (pop / 100) let rightpct (count turtles with [opinion >= 0]) / (pop / 100) file-print (word try "," iter "," ticks "," leftpct "," rightpct "," avg-opinion "," opR "," opL "," prevR "," prevL "," inflR "," inflL "," links-dead "," links-create "," inversion "," change "," total "," fractale "," major) end to csv-end if csv-open? [ file-close set csv-open? false ] end
There is only one version of this model, created 3 days ago by Pierre-Alain Cotnoir.
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Parent: Version_20250927-1_Spread of Opinions Influenced by Group Effects reward metablock plus memes v2
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