142 paired simulations from Scott E. Page's Model Thinking — Agent-Based Models and System Dynamics for the same families of problems, with a deluxe second pass of visually upgraded variants.
Heterogeneous agents, local interactions, emergent macro patterns. Page's foundational examples of how simple rules produce surprising aggregates.
Mild same-type preferences tip a mixed neighborhood into segregated patches.
ABM 02Heterogeneous quality thresholds and peer effects ignite — or fail to ignite — an ovation.
ABM 03Distribution of riot thresholds determines collective participation and tipping.
ABM 04Two-state cellular automaton with universal computation lurking in B3/S23 rules.
ABM 05Self-organized criticality: avalanches whose size distribution follows a power law.
ABM 06Trees grow, lightning strikes, fires sweep — a canonical SOC model.
ABM 07Diverse temperature thresholds keep the hive thermostat tighter than uniform thresholds do.
ABM 08Diversity of activation thresholds boosts hive responsiveness to threats.
ABM 09Local imitation produces stable cultural domains — and persistent borders.
ABM 10Connectivity through a random lattice undergoes a sharp phase transition near p≈0.593.
ABM 11Contagion spreads through a 2D contact lattice with recovery and immunity.
ABM 12Reynolds' three rules — separation, alignment, cohesion — produce flocks.
ABM 13Pulse-coupled oscillators self-synchronize through phase nudges.
ABM 14Cooperators and defectors play neighbors; clusters of cooperation persist.
ABM 15Epstein-Axtell agents harvest a regrowing landscape — and inequality emerges.
ABM 16Each agent copies a random neighbor; opinion domains coarsen toward consensus.
ABM 17Inductive predictors converge on the carrying-capacity equilibrium of a coordination game.
ABM 18Path-dependent sampling: early draws lock in proportions across runs.
ABM 19Three-strategy cyclic dominance yields rotating spirals — non-transitive coexistence.
ABM 20NetLogo's classic three-trophic ecology with energy budgets and reproduction.
ABM 21Many random walkers reveal diffusion, first-passage, and the central limit theorem.
ABMStocks, flows, and feedback loops. Page's lens for problems where aggregate continuous variables and delays drive the dynamics.
Continuous oscillations from coupled ODEs — the SD twin of wolf-sheep.
SD 23Stocks of S, I, R flow with rate equations dβSI/N and γI.
SD 24Adds an exposed compartment — incubation delays change the curve shape.
SD 25Carrying capacity caps exponential growth via a balancing loop.
SD 26Innovators p plus imitators q produce the classic adoption S-curve.
SD 27Inflow vs outflow — Sterman's litmus test for stock-flow intuition.
SD 28Order delays amplify upstream variance through a four-tier supply chain.
SD 29A renewable resource collapses under unconstrained extraction.
SD 30Three coupled ODEs — sensitive dependence on initial conditions made visible.
SD 31Capital, labour, depreciation and technology in a single feedback diagram.
SD 32Strategy frequencies follow fitness gradients — evolutionary game theory in continuous form.
SD 33Lagged supply meets present demand — convergence, oscillation, or divergence.
SD 34Population, resources, pollution and capital — Forrester's World3 in miniature.
SD 35Closing a gap — slowly. Long perception delays produce overshoot.
SD 36Strogatz's love equations: linear feelings, nonlinear courtship.
SD 37Cohorts age through stages — demography as serial stocks.
SD 38Knowledge accumulates and feeds back into productivity.
SD 39Reinforcing peer adoption vs balancing recovery — the addiction archetype.
SD 40Atmosphere, ocean, biosphere stocks linked by uptake and emission flows.
SD 41State-transition probabilities settle into a stationary distribution.
SD 42Side-by-side anatomy of the two atomic units of every SD model.
SDVisually upgraded second-generation ABMs — vibrant colormaps, glow trails, multi-panel layouts, and high-density agents. Networks, continuous CAs, reaction-diffusion, active matter, swarms, and statistical mechanics.
Beta-distributed individual tolerances; histogram + segregation timeline.
ABM ✦ 44Watts-Strogatz small-world Schelling — rewiring changes outcomes.
ABM ✦ 45Bounded-confidence opinion dynamics fan into clusters.
ABM ✦ 46Cascade size on scale-free networks; click-to-seed.
ABM ✦ 47Network structure modulates time to consensus.
ABM ✦ 48HSL-mapped cultures with magenta-glow boundaries.
ABM ✦ 49Rules 30, 90, 110, 184, 250 in plasma colormap.
ABM ✦ 503-state CA — electric cyan ON, magenta DYING, glow.
ABM ✦ 51B3678/S34678 — symmetric in both binary states.
ABM ✦ 524-state CA — diodes, oscillators, AND gates; click to draw.
ABM ✦ 53Multi-rule ants paint highways from chaos.
ABM ✦ 54Continuous space-state generalisation of Conway — orbium organisms.
ABM ✦ 55Rafler's continuous CA — soft alive blobs that crawl.
ABM ✦ 56Spots, worms, mazes, mitosis, coral, solitons.
ABM ✦ 57Excitable medium with rotating spiral waves.
ABM ✦ 58n-state cycle producing rainbow spiral waves.
ABM ✦ 59Belousov-Zhabotinsky-like CA — pulsating spirals.
ABM ✦ 601500 self-propelled particles — order/disorder phase transition.
ABM ✦ 61Distance-weighted alignment converges globally.
ABM ✦ 62Motility-induced phase separation in self-propelled disks.
ABM ✦ 63Three-zone fish schooling with escape response.
ABM ✦ 64Reynolds boids navigating draggable obstacles.
ABM ✦ 65Two pheromone fields, glowing trails between nest and food.
ABM ✦ 66200K particles weave organic vein networks.
ABM ✦ 67Stigmergic chip sorting from random scatter to neat piles.
ABM ✦ 68Spiral waves drive slime-mold aggregation.
ABM ✦ 69Metropolis dynamics; phase transition at T_c≈2.27.
ABM ✦ 70Multi-state generalization of Ising — domain coarsening.
ABM ✦ 71Continuous spins; vortex/antivortex pairs at low T.
ABM ✦ 72Witten-Sander fractal cluster with glowing tips.
ABM ✦ 73Cluster grows via random boundary additions.
ABM ✦ 74Drop thousands of grains at center for fractal symmetry.
ABM ✦ 75Giant component emerges sharply at p_c=1/N.
ABM ✦ 76Rewiring β reveals C(β)/L(β) sweet spot.
ABM ✦ 77Preferential attachment yields scale-free degree distribution.
ABM ✦ 78Punctuated equilibria visible as plasma spacetime image.
ABM ✦ 79Disease spreading edge-by-edge with flash transitions.
ABM ✦ 80Vocabulary convergence to a single global word.
ABM ✦ 81Aligned dyad converts neighbors — coarsening to consensus.
ABM ✦ 82Random groups vote; tipping near p_c=0.5.
ABM ✦ 83Population dynamics converge to mixed equilibrium.
ABM ✦ 84Random pooling produces exponential wealth distribution.
ABM ✦ 85Even fair coins concentrate all wealth in one agent.
ABM ✦ 86Challet-Zhang strategy-evolution attendance.
ABM ✦ 87PSO on Rastrigin — particles converge to global best.
ABM ✦ 88Bit-string evolution with selection, crossover, mutation.
ABM ✦ 89DE/rand/1/bin on multimodal landscapes.
ABM ✦ 90Depth-coloured flocking with rotating camera.
ABM ✦ 911500 particles trace the Aizawa strange attractor.
ABM ✦ 92Hexagonal dendritic crystal growth with six-fold symmetry.
ABM ✦Second-generation SD models with multi-panel time-series, phase portraits with vector fields, Poincaré sections, and causal-loop diagrams. Oscillators, chaos, ecology, epidemics, macro, climate, archetypes.
Limit cycle from nonlinear damping — sinusoidal to relaxation.
SD ✦ 94Phase portrait + Poincaré section — chaos at γ=0.30.
SD ✦ 95Single-loop strange attractor with turbo z-coloring.
SD ✦ 96Double-scroll attractor from a piecewise-linear diode.
SD ✦ 97Resonance peak revealed by frequency sweep.
SD ✦ 98Lagrangian chaos with phase portrait + Poincaré.
SD ✦ 99Symplectic integration with figure-8 choreography preset.
SD ✦ 100Cobweb + iterates + full bifurcation diagram.
SD ✦ 101120K-iter glowing strange attractor.
SD ✦ 102Tori-to-chaos transition on the (θ,p) torus.
SD ✦ 103Period-doubling cascade in fish dynamics.
SD ✦ 104Smooth convergence vs Ricker oscillation.
SD ✦ 105Surplus production with MSY and overfishing collapse.
SD ✦ 106Four regimes via competitive Lotka-Volterra isoclines.
SD ✦ 107Hastings-Powell food web — limit cycles, chaos.
SD ✦ 108Endemic oscillations; seasonal forcing toggle.
SD ✦ 109Herd-immunity threshold p_c = 1 − 1/R₀.
SD ✦ 110Adds D compartment; CFR converges to μ/(μ+γ).
SD ✦ 111Host density vs mean parasite burden oscillations.
SD ✦ 112Vector-borne R₀ = ma²bc / (rμ).
SD ✦ 113Capital per worker steady state k* with phase line.
SD ✦ 114Balanced growth path on log axes.
SD ✦ 115Endogenous knowledge growth from research labour.
SD ✦ 116Predator-prey of employment vs wage share.
SD ✦ 117Endogenous limit cycle from nonlinear investment.
SD ✦ 118Adaptive expectations break the trade-off.
SD ✦ 119Fiscal/monetary shocks shifting equilibrium.
SD ✦ 120Adaptive λ stabilizes the price oscillation.
SD ✦ 121Endogenous boom-bust from debt accumulation.
SD ✦ 122Black/white daisies thermoregulate the planet.
SD ✦ 123Snowball-warm bistability from albedo feedback.
SD ✦ 124Reinforcing thaw loop tips climate.
SD ✦ 125Clear/turbid alternative stable states with hysteresis.
SD ✦ 126Critical population threshold A separates extinction from K.
SD ✦ 127Three fixed points; outbreaks via saddle-node bifurcation.
SD ✦ 128Two-box thermohaline circulation collapse under freshwater.
SD ✦ 129Climate-like chaotic attractor of jet vs eddies.
SD ✦ 130Refuge stabilizes coexistence — closed orbits → spiral.
SD ✦ 131Age-structured Leslie matrix with eigenvalue λ.
SD ✦ 132Sigmoidal birth/death rates over development.
SD ✦ 133Coupled K, L, A produce 50-year economic cycles.
SD ✦ 134Successive Bass diffusions across tech generations.
SD ✦ 135Word-of-mouth + advertising + price + repeat purchase.
SD ✦ 136Generic fold bifurcation with path-dependent F sweep.
SD ✦ 137Goals decay to track current state — drift downward.
SD ✦ 138Symptomatic fix erodes capacity for fundamental solution.
SD ✦ 139R loop dominates early; B loop dominates later.
SD ✦ 140Construction delay produces classic over/undershoot.
SD ✦ 141Order-fill delay creates beer-game oscillations.
SD ✦ 142Three pipelines with delays propagating step/ramp/pulse inflows.
SD ✦