NetLogo User Community Models

How to share your models

We encourage users to share your models with the NetLogo user community. You may upload your model through our model upload page. The web site will automatically create a web page for your model. Contributed models are credited to their authors.

We also have a model URL submission page. Use it if you prefer to host your model on an external web site.

The models

These models are contributions from the user community and are not included with NetLogo. These models are authored by the individual contributor and are not checked by the CCL staff.

Added Jun 2008

The Bugs of Nyarlathotep by Andre Ourednik To explore NetLogo's capabilities as a game engine, I've made this 3-level game entirely programmed with NetLogo3.1.4. Its storyline is loosely inspired by some of the works of H.P. Lovecraft. An offline version, with sounds, is available for download. Feel free to add your own levels to this game.

Retroactive Mechanisms of Segregation by Andre Ourednik This model combines Schelling’s spatial segregation model, Epstein&Axtel's SugarScape and a demographc model of dependency between household fertility rates and socio-economical status, in order to illustrate how a spatial segregation pattern can emerge from an initially (socially as well as spatially) homogenous population of households. It also illustrates retroaction of spatial segregation on social polarity as en effect of spatially inhomogeneous taxing mechanisms.

Cooler Model by Annette Brickley Dynamical systems models are powerful tools for studying many phenomena in Earth Science. These models (often rather sophisticated) are in increasingly wide use as research tools in hydrology, geochemistry, petrology, oceanography and climatology. This is a simple dynamical model used to develope insight into seemingly complex physical phenomena.

Global Carbon Cycle by Annette Brickley This model illustrates the movement of carbon through the natural environment.

Gottman 1 by Victor Wooddell This is a simulation using the System Dynamics Modeler of some actual data collected by John Gottman (Gottman, et al. 2002). Gottman originally develop a non-linear equation to explain the data he collected on married couples participating in his so-called "Love Lab". This was an experimental set-up where he would take 15-20 minutes of video of married couples freely discussing an issue that they disagreed about. He and his colleagues would code the resulting data and use the scores to predict whether or not the couple would be divorced within three years.

Added May 2008

Wolf Sheep Predation Refuge by Wolf Sheep Predation Refuge Version This model explores the stability of predator-prey ecosystems in the presence of a refuge area for preys. Such a system is called unstable if it tends to result in extinction for one or more species involved. In contrast, a system is stable if it tends to maintain itself over time, despite fluctuations in population sizes.

Colonialism by Desi Ariyadhi Suyamto This is a simple model, an initial attempt to clearly understand why colonialism in its various forms (including corporatocracy in neo-liberalism) sufferring the victims by disrespecting human rights in many ways. Using biological point of view, colonialism is paraciticism symbiosis.

Watercycle1 by Ed Hazzard This model of the water cycle was developed for grades 3-6. It shows the major paths that water takes when traveling around the earth.

PedestriansV1 by Singhathip Mickaël This model simulates what happens when people who move at different speeds interact when sharing finite space.

Added Apr 2008

CBNM-simu by Jun Wang This model illustrates how a small array of microscopic loops (CB modules), each coupled with a neuromuscular (NM) module, can generate motor commands and movements in the "center-out" task, a classical movement task that requires a subject to move rapidly from a starting point in the center of a workspace to one of eight radially symmetric targets.

Grass by Grass growth Simulates the growth of grass in relation to various environmental conditions.

Added Mar 2008

Marble-Fall-Icosystem-4 by Paolo Gaudiano This is a model of the "Bean Machine", a simple analog model of how a binomial distribution approximates a Gaussian. Marbles drop from an opening in the top, bounce over several rows of pegs, and are collected in bins at the bottom. The twist in this case is that pegs can be biased to push marbles left or right, resulting in all sorts of distributions.

Shopsim-sc by Zhenjiang SHEN, Ping CHEN, Mitsuhiko KAWAKAMI This model is aiming to explore using approach of multi-agent simulation (MAS) to analyse the impact of public transportation policies on shops's market share, especially on shops in central area of local cities in the context of Japan. This MAS model called as Shopsim has been developed to analyse central area regeneration policies that include the public transportation policy. A basic scenario (BS) and a scenario of implementing combined public transportation policies (CTPS) are designed to illustrated how to analysing the impact of transportation policies using Shopsim. Household agents in scenarios have to make their decision on where to go shopping and choose an appropriate travel mode (walking, bus or car) to go there. The spatial market pattern and market statistics of central area shops can be generated from these individual shop-choice behaviours. Through comparing market situation in the CTPS to that in the BS, the impacts of public transportation policies on shop's market share can be analysed.

Quorum_Sensing by Luís César da Costa , Marcelo Trindade dos Santos and Gilson Antônio Giraldi The discovery that bacteria are able to communicate with each other changed our general perception of many single, simple organisms inhabiting our world. Instead of language, bacteria use signalling molecules which are released into the environment. As well asreleasing the signalling molecules, bacteria are also able to measure thenumber (concentration) of the molecules within a population. Nowadayswe use the term "Quorum Sensing" (QS) to describe the phenomenonwhereby the accumulation of signalling molecules enables a single cellto sense the number of bacteria (cell density). In natural environments,there are many types of bacteria with a variety of signalling molecules.As they employ different languages they cannot necessarily talk to allother bacteria. Presenting the model of cellular automata proposed todescribe the main mechanisms of Quorum Sensing where Vibrio & Fischeri,and its model using the concept of Multi-Agents System.

Added Feb 2008

Traffic_Simulation by Andrew Lansdowne Traffic simulation tool developed with a view to analysing the likely effect of congestion-reducing schemes, in particular high occupancy vehicle lanes. It allows you to design a road system, with sources, sinks, traffic lights, speed limits, and then simulate running vehicles around it. It shows a time-space diagram to visualise the motion of vehicles, and a flow-density diagram to visualise vehicle flow rates at different vehicle densities. Includes a number of test road systems, follow links under Simulation Runnable Applets.

Copying_and_Associating_1 by Derek Rush COPYING and ASSOCIATING -1 is a beginning in exploring the extent to which the procedures of copying and associating may be in use in the brain of a creature. It illustrates how a crossword puzzle may be solved using WORDS that have been COPIED into a memory with some regard taken for their ASSOCIATION, so that answer words and clue words are likely to be reasonably close together.

PopGen_Fishbowl_1 by Thomas C. Jones PopGen Fishbowl 1.0 is an agent-based population genetics simulation. The program contains the tools to conduct virtual experiments violating all the assumptions of Hardy-Weinberg theory (small population, selection, mutation, migration, and non-random mating).

Zombie_Infection_2 by Asymptote A simulation of the social ramifications of a zombie epidemic on an organized society.

Added Jan 2008

Photon_transmissivity_2 by Ted Wong Greenhouse gases (GHGs) already completely block some wavelengths of radiation from leaving the atmosphere. If additional GHGs cannot reduce those wavelengths' transmissivity, then how would an increase in GHG concentration exacerbate global warming? In two ways: by increasing absorption of other wavelengths and therefore decreasing overall transmissivity; and by concentrating photon absorption (and therefore heat) in the lower atmosphere.

March by Elio Marchione The classical March model (1991), this simulation shows the mutual learning between an organization and its members, and how this affects the learning performance of the whole organization. Developed by CLOE, University of Naples.

Miller by Elio Marchione This Model qualifies and extends March's model (1991). Miller and al. (2006) add direct interpersonal learning. By allowing for interpersonal learning in organization, they recognize that face-to-face interaction can be critical to learning performance. Developed by CLOE, University of Naples.

SimHeart by Asymptote HeartSim is a simulation of the electrical activity in the heart. It's capable of producing many of the commonly-observed arrhythmias, such as ventricular fibrillation and atrial flutter

NetLogoGreenHouse by Aaron Unger A simple model of how sunlight, albedo, CO2 and clouds all work together to change the global earth temperature.

Added Dec 2007

Randomly_Walking by shashank singh simple model of randomly walking , reproducing human population, (a) with two sexes as usual (male female) (b) implemented, through breed ; (c) only females can reproduce, (d) all agents eat food to live,(food is green , no food is brown),food regrows after some time (e) all agents grow in size according to their age and after some threshold value die due to old age (f) agents die due to food starvation too(g)females expend more energy in reproducing

SSCrazyPingPong by Serg My first model for NetLogo 3.1.4

Added Oct 2007

Mouse_Aorta_Initial_Model by Heather Hayenga No description.

Urbanization_MC by Andr� Ourednik & Pierre Dessemontet The very existence of urban formations on all inhabited continents and throughout the history of mankind since the 3rd millennium B.C. leads to suppose a tendency of some structured societies to maximize interaction by minimizing physical distance. Were this tendency unconstrained, it should eventually lead to the concentration of all of the societyÂ’s population into one single point: a situation only partially realized by the distribution of urban populations at the global scale. Models of constraints preventing its realization have thus to be proposed. We have set up one such model, using agent based simulation of food production and accessibility, in order to account for the structural constraints particular to the physical space. The simulations have notably shown that, while necessarily emerging from a society investing agricultural surplus into the upholding of specialists, an upper limit to city-growth is imposed by the phenomena of spatial friction

Games by Carlos Gershenson This model is inspired in multi-agent games that people can play, following simple rules to observe emergent global patterns/behaviours. They could be seen as simpler versions of Craig Reynolds's "Boids" [1], or Hiroki Sayama's "Swarm Chemistry" [2], with the advantage that you can play these with real people.

Added Sep 2007

Homework_highschool by Daniel Kuchta How to use this simulation:Choose the number of students that will be eligible for school. It allows you to choose 1 to 100 students. Choose the percentage of students that will actually attend the high school. When at school and more than 50% students go to school, all the students will have to study 5 hours a day to graduate. If less than 50% of the students go to school, only 3 hours a day are necessary to graduate.

Light-Absorption by Ed Hazzard This model looks at the absorption of light by colored filters. In this case the filter is a chamber filled with gas molecules that absorb specific wavelengths of light. It demonstrates that a filter absorbs everything EXCEPT its apparent color.

Homo_Bellicus by Andrie Kraaij War is something of humans, we're convinced of that. Only after humans were present on earth did war start. But is that true? What if war was there first...

Evolutionary_Game_Theory_Big_Bird_Replicator_Dynamic by Jeff Russell A two-player, replicator dynamic model of evolutionary game theory is simulated in this program. The model contains two breeds of birds that randomly play a simultaneous game with other birds. Each breed is "hard-wired" to play their breed's strategy. The model allows the user to set different payoffs for each of the four possible matches between breeds, thereby simulating situations of repeated cooperation and/or competition. These payoffs determine each type's reproductive success. The model also allows the user to change the overall birth and death rate. The program contains a series of self-directed questions regarding replicator dynamic stability. The self-directed questions also explain how to simulate the well-known "Hawks and Doves" game and then compare stability with a mixed Nash equilibrium. This model is used in conjunction with the simpler "Evolutionary Game Theory: Mayberry" model to teach evolutionary game theory.

Evolutionary_Game_Theory_Mayberry_ESS by Jeff Russell The Evolutionarily Stable Strategy (ESS) idea found in evolutionary game theory is simulated. The model uses a two-lane road and two driver types. If a right-hand side driver meets a left-hand side driver, one driver dies. The process continues until only one driver type remains as the surviving strategy. The program contains a series of self-directed questions regarding ESS that include exercises in how ESS relates to Nash Equilibrium. This model is used in conjunction with the more complex "Evolutionary Game Theory: Big Bird Replicator Dynamic" model to teach evolutionary game theory.

Added Aug 2007

SolarSystem-Timer by Ed Hazzard This model is a modification of "Solar System" by Jerry James (2/13/03). This version focuses on the relative orbit times of the planets. It adds an orbital counter so that one can compare the radii versus the orbiting times of the six historical planets.

Pathfinder by Robert Goldstone This is an updated version of the model I submitted in December 2002. This simulation shows how close-to-optimal paths can be found around obstacles with a decentralized system. In traditional Artificial Intelligence, the search for a good solution is typically viewed as a process of adding steps to a solution and backtracking when dead-ends are found. The alternative method pursued here is to have simple agents locally influence each others position. They globally form a path even though no agent by itself represents an entire solution...

Cluster by Lubrano Lavadera David Rosario The objective of this model is to study the dynamics of learning processes within industrial clusters, in relation to the structural properties of network relations.

MASforSeg by KHOUADJIA Mustapha Redouane This program presents an adaptative approach based on a multi-agents system for the images segmentation. This system is constituted at the micro level of autonomous entities, which deployed on the image. They are equipped with a capacity to estimate the homogeneity of a region from their current locality. Each entity exhibits several behaviours in response to the local stimulus. It can migrate, reproduce, or diffuse within the image. Various entities explore the image and label the pixels when they belong to homogeneous segments. The interactions at the micro level allow the emergence of a new feature that is segmentation of the image.

Added Jul 2007

Toy_Infection_Model by Gary An This is a simple model of the acute inflammatory response to infection. This model is an extremely reduced version of the "Innate Inflammatory Response" model seen on the Community Models page from May 2004, and contains only some essential components of the body's response to infection. The background patches of the model represent a generic tissue that contains a "tissue-life" patch variable that keeps track of the damage done.

SAfri_Models by Baba Kofi Weusijana These models are based on the Wolf-Sheep Predation Model that tries to see what conditions will produce a stable ecosystem without extinction of humans or cows.

Gas_Distillation by George W. Dombi Builds on previous Gas Lab models and tries to implement changes in particle size, mass and the influence of 'gravity'. Model consists of a two part container with a hot side to heat the gas and a cool side to let it condense.

Added Jun 2007

Bifurcacion2 by Abdiel E. Caceres-Gonzalez This model is an application of the famous Bifurcation diagram of logistic equation: X[t+1] = k * X[t] * (1 - X[t]); with k=0..4 and X[t]=0..1

Negotiations by Zvi Vlodavsky. Doron Zarchy This model simulates negotiations between 3 types of agents, each with a different "toughness" property. It shows how the toughness affects the outcome of the negotiations in different environments. It also demonstrates dynamic toughness strategies in which the toughness is determined dynamically according to the environment, attempting to yield good results in different environments.

Climate_change by Ed Hazzard This is a model of incoming and outgoing radiation from the sun. It demonstrates the effect on the average temperature of albedo, solar intensity, clouds, and CO2.

margherite by Stefano The model is a sort of Daisyworld with the presence of Turtles that eat the yellow flowers.The goal of the model is to show the balancing effect of life on the environment.

Bug_Hunt_Evolution by Christopher J Whalen This model is highly modified version of BugHunts Speeds to demonstrate evolution by natural selection and genetic drift. Bugs have several traits: color, hue, speed, size, and jitter. Meanwhile, the user, 'predator', has finite life which decreases over time if no bugs are caught, increases when bugs are caught, and decreases rapidly for a 'miss'.

Added May 2007

forestfire2 by dongxiaofei Simulation of forest fires

Epidemic_Typhoid_Fever_on_Disaster_Area by Agung Budi Sutiono, MD Epidemic Typhoid Fever on Disaster Area was inspired by tsunami disaster that hit asian countries. Typhoid fever is communicable disease caused by Salmonella typhii. It will easily spread to one and another especially on disaster area where hygiene and sanitation very poor.

Asteroid_Belt_Game by Asteroid Belt An old arcade game called "Asteroid Belt."

Big_Bang by David Bowen Simple Big Bang simulation. Shows how the Big Bang results in the pattern that distant stars are receding more rapidly. Reverse the recession to "run the movie backwards" and show how this recession velocity pattern supports the Big Bang.

Gaslab_Brownian_Motion by David Bowen Brownian motion simulation. See the spores execute the "drunkards walk." Normally the gas molecules are invisible, but you can make them visible to show how the drunkards walk originates.

Gaslab_Two_Color_Gas by David Bowen Statistical Mechanics illustration using a gas of identical particles except that there are molecules of two different colors. Can illustrate mixing of gases, pressure on a wall, and the irreversability of water melting ice.

Newtonian_Relativity by David Bowen Illustration of Newtonian Relativity. A car driving on top of a railroad flatcar illustrates the concepts of Newtonian Relativity and the simple addition of displacements and velocities.

Added Apr 2007

Quantum_Financial_Market by Carlos Pedro Gonçalves This is a evolutionary quantum game theoretical model of a financial market, introduced and tested empirically by C.P. Gonçalves and C. Gonçalves (2007).

SickTown by Gordon McDonald Studying the spread of infectious diseases in a small town environment.

AntSystem by Christopher Roach The Ant System algorithm can be used to find the shortest path in a graph by employing the same decentralized mechanism exploited by ant colonies foraging for food.

LogoMoth by Shawn Barr, Eric Charles, Owen Densmore, Stephen Guerin, & Nick Thompson LogoMoth models allow users to simulate an iterated prisonerÂ’s dilemma game (see http://en.wikipedia.org/wiki/Prisoner's_dilemma) in which preprogrammed strategies interact with each other by either cooperating or defecting and/or staying or leaving. LogoMoth is modified from the traditional model in two important ways: First, individuals may, depending on their strategy, choose to leave their partner. Second, leaving and being left (i.e., staying) may incur a cost.

Added Mar 2007

Bouncing_Ball by David McAvity This simulation models the internal dynamics of a bouncing ball. Ordered energy becomes more and more disordered as the ball bounces.

FractalMorph by David McAvity Fractal morph is a NetLogo implementation of Richard Dawkins biomorphs. Users mimic evolution by selecting fractals from a fractal landscape.

Vertical-Evacuation by Susanne Jul This model demonstrates "vertical evacuation," a technique for bringing people to safety by having them "go up" in buildings, for instance, in flooding or tsunami situations. The model implements two behaviors: seeking to go up (modeling people who receive and understand the warning, know what to do and do it), and seeking to get outside (modeling people who want to get out for whatever reason). It also illustrates socially transimitted behavior in the form of "directors" who are able to convince individuals around them to change their behavior.

Wireless-Coop-Mobile by Federico Albiero Model of cooperation a mobile ad-hoc wireless network based on WLAN (IEEE808.11) technology. Units move around randomly and establish cooperative clusters according to strategies in order to improve power consumption.

Added Feb 2007

Example-HPP-3D by Luís César da Costa and James Steiner In this model we apply stochastic models to study two variations of the Lattice Gas Cellular Automata (LGCA), introduced by Hardy, De Pazzis and Pomeau, called HPP model. These are discrete models based on point particles that move on a lattice, according to suitable and simple rules in order to mimic a fully particle dynamics.

Simulation_of_Inelastic_Collision by Sifat Momen This is a simulation that illustrates inelastic collision between two trolleys (in this case two model cars A and B) moving over a low-friction surface [Friction is too small and therefore can be neglected]. This is a classic simulation that shows that the total momentum is conserved i.e. total momentum before collision = total momentum after collision.

MEQU by Segismundo S. Izquierdo & Luis R. Izquierdo MEQU (Market Effects of Quality Uncertainty) is a model designed to study the effects of quality uncertainty and incomplete information on market dynamics. The main assumption in this model is that buyers form quality expectations about products based on their own past experiences and on the experiences of people they know.

Urban-Transition by lagarias Apostolos The model simulates the development of an urbanized area through the transition of land use from rural to urban. The model starts with a central city and a number of settlements distributed randomly around it. An attribute of the patches called ''possibility'' is used to determine the transition of tha land use when a certain threshold is reached. The growth starts rather slowly but finally starts to expand rapidly. Two conditions are used in two specific times to impose a boundary in urban development and therefore to preserve some undeveloped land. The total space is divided in two zones according to the distance from the center and therefore the possibility of land-use transition near the central city is greater.

Recrystallization by Markus Kasim Recrystallization comes from two words: re and crystallization. It means that there was a preceding crystallization process occurring in a material before the similar process occurs for the second times. Recrystallization happens in all kinds of material: metal, ceramic, polymer, as long as the material has crystal structure. This model represents the general appearance of recrystallization microstructure in materials.

Added Jan 2007

MMG by Cem D Implementation based on Daniel B. Stouffer's MG implementation.

Final_Preliminary_Model by Benjamin Roberts This is my first Evacuation model with one exit, one agent wide

Multi_Exit by Benjamin Roberts This is my second modeling allowing for variation among number and size of exits

Network_growth by Malik Koné This is a simulation of the growth of a social network based on the paper "Structure of growing social networks" (Emily M. Jin, Michelle Girvan, and M. E. J. Newman). The network presents social network characteristics, i.e. high clustering and low average geodesy.

Obstruction_Model by Benjamin Roberts This is my final model allowing for placing an obstruction or "barrior" in front of doorway causing agent organization.

ejb6 by Thornton Rose Simulation of Enterprise JavaBean (EJB) creation and execution on WebLogic 8.

web4 by Thornton Rose Simulation of sessions and transactions on WebLogic.

MG_cem_changed by Cem Dilmegani Majority-Minority game. Extended version of Minority Game Model. In this model, a variable percentage of the agents seek to be in the majority while the remainder of the agents seek to be in the minority. Read MG Model for implementation details like how scores are set and how agents choose strategies. Counterintuitive results: Memory=4 yields more efficient outcomes than Memory=12, especially when more than half the population wants to be in the majority. The information part will be modified, now it only contains information about the MG model.

Innovation by Michael Samuels Diffusion of Innovations - agent-based model examining the spread of innovations by word-of-mouth ("internal diffusion") and mass media ("external diffusion"). Two sets of innovations can be examined at once, allowing a second "disruptive" innovation to compete with a recently introduced technology.

Added Dec 2006

energy-conservation by Sifat Momen This is a simple model that illustrates that total energy in a closed system is conserved. In this model, a ball has been allowed to fall freely (under gravity), hits the ground and bounces back. The energy variation of the ball has been simulated in this model.

Added Nov 2006

Final Project by Matthew Colebeck Here is a simulation that describes Newton's Second Law.

Learning and Creativity by Derek A. Rush This model is a representation of the occurence of learning and creativity for a very simple, hypothetical creature. The creature is motivated by an urge that has to be satisfied and it is helped by learning from received inputs. Making this model and reviewing the probable origins of a creature's neurobiology has suggested a direction in which it may have been extended for larger brains.

CharityWorld-JASSS by Luis R. Izquierdo CharityWorld-JASSS is a model designed to show the emergent effects of floating-point errors in agent-based models. This is done by showing how the model behaves dramatically differently using floating-point arithmetic and using real arithmetic. CharityWorld-JASSS also illustrates how floating-point problems can be avoided by using two simple techniques: Tolerance Windows, and Round to n significant digits.

SpatRain by Desi Suyamto The SpatRain simulator described here is constructed to generate time series of rainfall that are fully compatible with existing station-level records of daily rainfall, but yet can represent substantially different degrees of spatial autocorrelation.

Added Oct 2006

Craps by Amelie Zeng This is Craps, the dice game (Without the gambling, of course.)

Added Sep 2006

Quicksort by pratik No description given

Added Aug 2006

AdoptLearnOnLine by Desi Suyamto This is a simple model about landscape transformation by farmers. The model simulates on how farmers decide to practice particular land use system on their plots, given that they have 3 choices available. The basic premise of the model is that farmers adopt certain land use system based on their knowledge about profitability of the system and their ability to generate capitals for establishment.

MusiqueMulti-Agents by Hervé Provini Modèle expérimental multi-agents pour la création musicale. Chaque agents a un comportement très simple. La mise en oeuvre d'une multitude d'agents et leurs interactions entre eux (et avec un signal entrant), donnent une émergence de forme musicale.

GarbageCan by Guido Fioretti The "Garbage Can" is a model of organizational decision-making. In the Garbage Can model, decision is made when the members of an organization apply a solution to an opportunity for making a choice. Note that solutions exist before problems, and that decisions can be made even without solving any problem. Eventually, a problem may be there to be solved, but this is not necessarily the case.

Added Jun 06

Example-HPP-mod by Luis Cesar da Costa This model demonstrates circular wave propagation using a cellular automaton on a square grid. The behavior of the waves approximates the Navier-Stokes equation, a well established fluid dynamics equation discovered in 1823.

Fitness_Landsacape by David McAvity Fitness Landscape is a NetLogo model that illustrates the principle of evolution as movement of a species through a fitness landscape over time.

Shock2004_Gut_Epithelial_Barrier by Gary An, MD This is an abstract model of Epithelial Cell barrier function. It is based on an epithelial cell culture model that looks at the effect of cellular tight junction status on permeability of the epithelial cell sheet.

DiffusionWithMembraneAsTurtle1 by Gary An, MD This is a simple model that looks at diffusion of molecules with and without the presence of a membrane with variable permeability. It also includes a very abstracted active transport pump that counteracts the permeability limitations of the membrane.

DiffusionWithMembraneAsPatch1 by Gary An, MD This is a simple model that looks at diffusion of molecules with and without the presence of a membrane with variable permeability. It also includes a very abstracted active transport pump that counteracts the permeability limitations of the membrane.

Added May 2006

sudoku-solver by Zammu no description given

multiagent by Marianna Caldana, Paolo Cova ed Umberto Viano The aim of our program is the creation of a financial market in which a single stock is traded; the agents (three categories) who act on such market are characterized by bounded rationality and differentiated into three types according to their behavior (Imitator, Fundamentalist and Stubborn); moreover, every agent has a tied budget, expressed by an endowment and a maximum debt they can reach before default.

Reinforcement Learning Maze by Joe Roop This model implements Q-learning (Watkins 1989) a one-step temporal difference algorithm in the area of reinforcement learning, a branch of artificial intelligence and machine learning.

Reinforcement Learning Wargame by Joe Roop This model implements Q-learning (Watkins 1989) a one-step temporal difference algorithm in the area of reinforcement learning.

Added Apr 2006

BirdAggression by Josh Rainwater no description given

2d_parity by hardik no description given

Added Mar 2006

Asynchronous_Backtracking_-_binary_random_problems by Ionel Muscalagiu This is the implementation of the Asynchronous Backtracking for the random binary problems

Added Feb 2006

Langtons_Ant_on_Infinite_Plane by Ivan Filippenko no description submitted

Added Jan 2006

ZombieInfection by Alex Fink This is a moderately faithful rewrite of Kevan Davis' Zombie Infection Simulation in NetLogo.Go play with the original model if you haven't yet; a lot of this documentation is a comparison with the original.

Good_Morning_Turtles_II by Michel Viacroze "This is the following model of "Good morning turtles". Now each turtle can have its own values for close,far,and color. see "Good morning turles" Each turtle is facing a single turlte. Each turle moves toward the turtle it is facing until it reachs a distance define by its "close" value, then it changes its mind and escapes in the opposite direction until the distance is equal to its "far" value. Then back again to try to reach the targeted turtle.

Added Dec 2005

ABTkernelgraphcoloring-new_interface by Ionel Muscalagiu "This is the implementation of the ABT kernel for the graph coloring problem."

LevelCrossing by Ales Janota Model of Level Crossing Operation.

Level_Crossing by Ales Janota The model shows operation of a level crossing installation. The macro-level pattern emerging from interconnections of micro-level behaviours of agents should ensure such conditions of operation that the longest and slowest road vehicle finding itself at the crossing (i.e. inside the hazardous area) just at the moment of activating warning lights (triggered by detection of an approaching train) is able to leave this area before the barriers are falling down.

THEmazegame by Evan Schwartz and Tom Slater This is a maze game for one or two people.

Atomic-Force by Corey Haddad Simulates long range attration and short range repulsion with many elements. Model info contains contact info for the author of this model as well as the waterfall and wireframe model.

Added Nov 2005

WaterfallFluids by Corey This is a simulation of a waterfall. Draw obsticals to the flow with the mouse. Change gravity and be sure to try the 'get dizzy' button.

wirefame 3d by Corey This model builds a basic 3-D enviroment out of a 2-D structure.

Drivers' Behavior In Car Park by Umeyr Kureemun This model was created as part of the project for STUDYING DRIVRES' BEHAVIOR IN CAR PARK. It was done at the National University of Singapore,and was supervised by the Associate Professor Chen Kan, Deputy Head, Department of Computational Science.(should be run on NetLogo version 2.1 otherwise it might not run properly)

mical by mical No description

Added Oct 2005

sudoku by Matt Hellige Those Sudoku puzzles are pretty popular these days. This model provides some help in solving them. Instead of trying to solve the puzzle for you, the model acts as an assistant, keeping track of possibilities and constraints and, in some cases, making suggestions.

CharityWorld-NL by Luis R. Izquierdo CharityWorld-NL is a model designed to show the emergent effects of floating-point errors in agent-based models. This is done by showing how the model behaves dramatically differently using floating-point arithmetic and using real arithmetic.

Game by Milo Guess My Number TO THE EXTREME!!A simple guessing game where it's you against the computer. You tell it what to guess out of, then set your four guesses. The easily understandable instructions will guide you step by step all the way to outsmarting your computer.Take a try at it. It's harder than it looks. Also, if you complete the challenge (2 guesses out of 70 or more and correct) you will get the cheat number, a number out of 50000 that will give you the answer whenever you want it. Go ahead and download Guess my number TO THE EXTREME!!

Added Sep 2005

Fishery by Bill Silvert A cellular automata model of the interaction between fishing boats and fish schools.

Added Aug 2005

drugsupply by Michael Agar, Stephen Guerin, Owen Densmore This is a model of a drug economy. The key point in the economy is that the bosses who employ dealers do so without actually holding drugs themselves, thus isolate themselves from direct risk of arrest. It includes a stripped down business life cycle for drug dealing: Hustling for deals, making a deal, going to the source to buy the drug (wholesale), carrying the drug to the buy and selling it, and returning to the boss to complete the deal. The players are exposed to risk of arrest via a cruising cop.

Added Jul 2005

05_wegesys_attrakt by Reinhard Konig und Christian Bauriedel the spread particles flow to a defined point and leave trajectories.

08_culturesFight09 by Reinhard Konig und Christian Bauriedel the behaviour-evolution of pixel cultures: cellular automata fighting about the given space.

wegesystem04 by Reinhard Konig und Christian Bauriedel the model create a self-organizing path-system

Artificial Financial Market II - Tail Risk by Carlos Pedro Gonçalves No description

pestilence by Joe Glessner A disease spread simulation.

machines-2005 by James Steiner This started out as a simulation of the behavior of surveyor-chain type chain links, and got out of hand. It could be extended to create one of those rag-doll physics engines that have been all the rage lately. Creates rigid links connected, in a stretchy way, to each other, with centrally located pivot-points. Links can be set to float free, or fixed to the background. They can be set to spin under "power". Different arm lengths may be set. Features an intuitive mouse-based drag-n-drop interface for selecting and positioning the links. Can also be used to stretch the chain, and make it go "twang!"Includes the ability to trace the path of the links, and to make noise when links touch the border.Features "rope-bridge", "chaos-tentacle" and infamous "crazy-machine" presets.

Added Jun 2005

burst by Dr. P. L. Birch The "burst" experiment designed by Prof. Brian Hartley was a key to our understanding of the biphasic, or ping-pong, nature of the mechanism of chymotrypsin and the other serine proteases.This model simulates that experiment and also demonstrates the important features of Hartley's chosen substrate, p-nitrophenyl acetate, by enabling comparison with a more "normal" substrate.

free-fall by Amelie Zeng This is a simple game where you try to get the balloon to land on the island thing...while avoiding birds and a sun and water...

feedback by Mathew Davies This is a simple molecular model of hormone-based feedback control in homeostasis, similar to (but simpler than) thyroxine-thyrotropin feedback in human metabolism. This model was developed to augment the study of the human body in an 8th-grade science curriculum.

worms by Mathew Davies This is a simple model of virtual 'worms' (which could be conceptually replaced with any organism displaying similar behaviors) in a resource-limited environment. The model displays both expected and unexpected population dynamics and was used to augment the study of mealworms in an 8th-grade science classroom.

Added May 2005

glycogen by Dr. P. L. Birch This is a simulation of the control of glycogen metabolism by the hormones, insulin and glucagon. It enables the user to vary the concentrations of the hormones and see the effects on the activities of the varios enzymes involved, and the changes that occur in glucose generation/storage.

frankmodel-2 by Erjiang Fu An initial urban airborne pollution model was built on 3-D version of NetLogo. NetLogo is a programmable modeling environment which is particularly well suited for qualitative modeling of a complex spatio-temporal system. This model simulates a typical grid city and natural environment. Additionally, three major types of pollution sources, namely point, line and area sources, were drawn in this study area and represent industry sites, automobiles and burning areas respectively. These pollution sources emit different major pollutants which disperse over land over time. The dispersal of airborne pollution under different weather situations and its influence to urban air quality were computer-generated.

Lorenz3D by Massimo Salzano The Lorenz system is a well known example of a simple system showing chaos. Its dynamics depend on many parameters.

Added Apr 2005

OneDimensionalElection by Mary Lynn Reed This is a model of the Median Voter Theorem. It illustrates one of the most annoying facts of two-party election politics: the tendency for both candidates to move their positions on policy issues to the center in order to win more votes.

Emotion & Motivation by Derek A. Rush Following upon two Netlogo models SELF-AWARENESS and IMAGINATION this model shows that a typical human relationship between EMOTION & MOTIVATION can be obtained with a simple iterative procedure and it extends the analysis to includePerception, Percepts, Memories, Display & Communication, to reach a conclusion about Consciousness.

3d-cube-maze by James Steiner This model generates, then traverses, a three dimensional maze, that is, a maze with corridors that go in all directions.Also demonstates a technique for moving the point-of-view to simulate rotating the view-space.

3d-maze by James Steiner A 2D Maze generator and navigator, implemented in 3D.

Shapefactory Model by Erik Johnston, Ning Nan, and Nathan Bos This is an agent based simulation of a lab experiment, Shape Factory. Shape Factory is a game for studying the collaboration patterns among distributed teams. In this game there are ten 'players', each with a different color, and each capable of producing one of five specialty shapes. The shapes represent work that agents can do for each other, and the five different shapes represents different 'skills'. In the default versions of the game (as run with human subjects) there are ten players and five shapes, so each shape is produced by two players.Players request shapes from each other to fulfill the shape orders they receive at the beginning of a round. Each tries to collect as many shapes as they can to fulfill its orders.

Added Mar 2005

Chemical Equilibrium elaborated by Russ Maurer This is a further development of the chemical equilibrium model from the Sample Models library. Temperature, activation energy, and collision orientation are included in the model. It is easy to change the amount of one of the chemicals, or the temperature, and observe the response of the system.

Asynchronous Backtracking-graphcoloring with flags by Ionel Muscalagiu This is the implementation of the Asynchronous Backtracking with Flags for the graph coloring problem. We solve the graph coloring problem using the ABT with flags algorithm from Gwen-Hua C., Wei-Li Lin, Chan-Lon Wang.Asynchronous Backtracking Algorithm with no effect of nogood explosion. In Proceedings International Conference on Computer, Communication and Control Technologies - CCCT2003, Orlando, Florida.

Added Feb 2005

ABT kernel-graphcoloring-derived in Asynchronous Backtracking by Ionel Muscalagiu This is the implementation of the ABT kernel - derived in Asynchronous Backtracking, for the graph coloring problem. We solve the graph coloring problem using the ABT kernel algorithm (derived in Asynchronous Backtracking )

Asynchronous Backtracking-graphcoloring by Ionel Muscalagiu This is the implementation of the Asynchronous Backtracking for the graph coloring problem. We solve the graph coloring problem using the ABT algorithm from "Makoto Yokoo and Katsutoshi Hirayama. Algorithms for Distributed Constraint Satisfaction: A Review.Autonomous Agents and Multi-Agent Systems, 3(2):185--207, 2000"

SOTL by Carlos Gershenson This simulation was exended from the model "Gridlock" by Uri Wilensky & Walter Stroup, which comes with NetLogo 2.0.0 (see more info at the bottom)Traffic lights try to "self-organize" for improving traffic.

sheep-fussyfemales by Ed Hazzard This is the sixth and last of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. Fussyfemales.nlogo shows the spread of a mutation when conflicting selection pressures are present.

sheep-mutation by Ed Hazzard This is the fifth of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. Mutation.nlogo shows the spread of an introduced mutation, with and without selection pressure.

sheep-populationA by Ed Hazzard This is the first of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. PopulationA focuses on the effect of initial number, grass regrowth rate, and birthrate.

sheep-populationB by Ed Hazzard This is the second of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. PopulationB focuses on uncontrolled growth.

sheep-populationC by Ed Hazzard This is the third of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. PopulationC focuses on the issue of extinction.

sheep-selection by Ed Hazzard This is the fourth of a series of models about adaptation and evolution for middle school. They all use a flock of sheep whose survival depends on eating grass. Selection.nlogo focuses on genetic drift in a variable trait of better or worse teeth, using Mendelian genetics.

LNmodel127-articleVersion by Rob Koper Simulation of drop-out and student retention in a simulated learning network (paper will be published in the JASSS journal (http://jasss.soc.surrey.ac.uk/JASSS.html).

ABT kernel -graphcoloring-derived in Distributed Dynamic Backtracking by Ionel Muscalagiu This is the implementation of the ABT kernel - derived in Distributed Dynamic Backtracking, for the graph coloring problem.

ABT kernel-graphcoloring-derived in Asynchronous Backtracking-Yokoo-with temporary links by Ionel Muscalagiu This is the implementation of the ABT kernel - derived in Asynchronous Backtracking (Yokoo) with temporary links, for the graph coloring problem.

ABT kernel-graphcoloring by Ionel Muscalagiu This is the implementation of the ABT kernel for the graph coloring problem.

Added Jan 2005

AWCS with nogood processor centralized for the graph-coloring problem by Ionel Muscalagiu This is the implementation of the Asynchronous Weak-Commitment Search with nogood processor for the graph coloring problem.

Simulation de la recherche de nourriture par les fourmis (Ant Food Search Simulation) by Aurélien Saint Dizier An applet, in French, showing how the ants looking for food "choose" the shortest path, if the parameters are correctly set

Recherche du plus court chemin entre plusieurs villes (Traveling Salesman Problem) by Aurélien Saint Dizier An applet, in French, showing the resolution of the Travelling Salesman Problem based on the algorithm developped by Marco Dorigo

Formation du cercle (Circle Formation) by Aurélien Saint Dizier An applet, in French, showing how a set of points "automatically" form a circle, if the parameters are correctly set

NukeSnake by Jim Lyons This two-player arcade game is a cross between "snake" and "tank" games, and is named after the popular Macintosh shareware game by David Riggle that inspired it. It requires NetLogo version 2.1 or higher since it uses keyboard input for the controls.

economicexchange by rinke Hoekstra the model tries to simulate banking and economic exchange in a small community

Added Dec 2004

organizer2 by Kazmer Karadi Demonstration of A. K. Dewdney's idea, presented in Scientific American, that explores how people organize their space in a digital party.

Added Nov 2004

AWCS with the resolved-based learning for the graph-coloring problem by Ionel Muscalagiu This is the implementation of the Asynchronous Weak-Commitment Search with the resolved-based learning for the graph coloring problem.

lac operon by Steven Brewer This is a model of the regulation of gene expression based on the lac operon: a bacterial gene that produces an enzyme that breaks down lactose, a complex sugar, into simpler sugars: glucose and galactose. This gene is only transcribed when lactose is in the environment. This system was one of the first models of gene expression described.

Unknown Gene Expression by Steven Brewer This is a model that offers a series of "unknown" problems for students to explorein learning about gene expression systems.

Logical Promoter by Steven Brewer This is a model that demonstrates how a gene expression system can implement the full set of logical operators (AND, OR, NAND, NOR, and XOR). The expression of two genes influences the expression of the third gene, either turning it off or on, based on which logical operator has been selected.

Added Oct 2004

ball-fall-2004 by James Steiner This is a simple simulation of falling particles.

chain-of-fools-2004 by James Steiner A chain of linked turtles. They follow each other. That is, each link as a "leader". Each link steps toward its leader, until it is some minimum distance, if the leader is too close, the link steps away at a preset angle.

ABTkernel by Ionel Muscalagiu We solve the N-Queens problem using the ABT kernel as outlined in"Christian Bessiere, Arnold Maestre, Pedro Meseguer.The ABT family.In Proceedings of JFNP, 2002."

DisDBgraphcoloring by Ionel Muscalagiu This solves the graph coloring problem using the Distributed Dynamic Backtracking algorithm from Christian Bessiere, Arnold Maestre, Pedro Meseguer.

DisDBnqueens by Ionel Muscalagiu This model solves the N-Queens problem using the Distributed Dynamic Backtracking algorithm from Christian Bessiere, Arnold Maestre, Pedro Meseguer.

cruise by Owen Densmore This is a proof of concept for including GIS into NetLogo for a dynamic Car Cruising model within the Santa Fe downtown area.

Bignum_Routines by Michael Kuyumcu Reporters for doing arbitrary-precision and bignum math for integer and floating-point numbers. Reporters are listed and described in the info window of the model.

Added Sep 2004

Drugtalk by Michael Agar Drugtalk models how rates of use of an illicit drug result from user experiences and diffusion of those experiences through social and spatial networks.

hypercycle by Joerg Hoehne This model simulates a hypercycle described by Eigen and Schuster 1979. A hypercycle is a prebiotic model which shows how stable structures (e.g. life forms) can or will emerge because of cyclic support of self replicating molecules to other self replicating molecules. This model can simulate up to 10 different molecule types.

Added Aug 2004

HIVSIM by Wilfred Ndifon HIVSIM is an agent-based simulation of HIV immunodynamics that is currently being developped in NetLogo. It allows users to investigate dependencies between various components of the cellular and humoral immune responses to HIV. Users can interactively manipulate simulation parameters (e.g., the number of Th, Tc, and B cells, and the infectivity of viral particles) and, in real-time, observe graphical plots of the results. Additionally, users can simulate antibody and anti-retroviral therapies at various stages of infection (e.g., the user can introduce into the simulation antibodies with affinity for the dominant HIV epitope). HIVSIM is still a work in progress. As time permits, the underlying model will be further calibrated against experimental data to make it robust and applicable to the qualitative evaluation of hypotheses on HIV immunodynamics.

accurate_clock by Erik Johnston This is a simple netlogo model to simulate a clock. It has no moving part and no moving turtles (just rotating turtles and turtles that change size).The clock can be set to any time and once set is as accurate at your computer clock.

tictactoe by Bertram Zinner This is the familiar Tic Tac Toe game programmed in NetLogo where you can play against the computer.

Added Jun 2004

DrugPropagation by Robert Rohrkemper and Josh Savory The primary goal of the Drug Simulation is to model the propagation of drug addiction through an infected population. The secondary goal of this model is to determine whether making drugs illegal or legal is more effective in preventing the spread of drug addiction.

Added May 2004

ProteinSynthesis by John Van Heukelem Protein synthesis simulation.

ElFarolBarProblem by Mark Garofalo El Farol is a bar in Santa Fe, New Mexico, at which a band plays Irish music on Thursday evenings. The bar is enjoyable only if it is not too crowded (say more than 60% of the agents). Trying to decide whether or not to go to El Farol is what Arthur's, 1994, "El Farol bar problem" is about.

Innate Immune Response by Gary An This is a model of the Innate Immune Response, which is the body's initial response to injury/infection. It is a cellular level model that focuses on the interactions between blood-borne inflammatory cells and the endothelial cells that line capillaries. It is a ported version of a StarlogoT model that was the source for a paper that is currently under review by the Journal of Critical Care Medicine. The model is intended to qualitatively reproduce the body's response to injury/infection, with particular emphasis on what happens to patients in the Intensive Care Unit.

Binary Counter by Teresa Carrigan BinaryCounter demonstrates counting in binary, and gives the decimal equivalent of the bit pattern for various data representations. This demonstration will help you understand integer overflow and the problems it can cause when undetected. It can also ask you questions, to see how well you understand the concepts.

Added Apr 2004

StackMachine by Teresa Carrigan Stack Machine Simulator. This is a model of a stack machine, also known as a zero-address computer. The simulator may be used to verify handwritten programs and to demonstrate the action of a stack machine using randomly generated programs. The model also demonstrates conversion from postfix (Reverse Polish Notation) expression to the normal infix notation.

5 Short-term-memory-voters by Michael Kuyumcu This short-term memory voter simulation builds on an idea presented by Howard Gardner. Imagine each voter out of a population changes her or his political opinion every day - just after visiting one of his four direct neighbors, she or he adopts the neighbors political opinion. Guess what kind of sytemic behavior will emerge over time.

beergame by Owen Densmore An agent based model of John Sterman's Beer Game. The beer game studies irrational decision behavior induced by delays in supply chain management. It uses a board game and cards to simulate the supply chain flow.

Added Mar 2004

bloodcells by Elio Ramos This is a simulation of the control mechanism for the production of white blood cells based on Mackey-Glass (1977).

ThermicRXN by Mitchell Hull This model demonstrates the connection between chemical reactions and the free energy or heat of the system.

Genetics and Cellular Automata by Theodore G. Wong This page holds a colle