Key Concepts

Our agent-based modeling environment is the Framework for Reconstructing Epidemiological Dynamics, or FRED. It is important to make a distinction between the different aspects of FRED that you may encounter. This includes the following concepts.


The FRED Modeling Language refers to the programming language defined by FRED. This language was built by Epistemix to simplify the construction, execution, and understanding of agent-based models. The definition and use of the FRED language is documented in the FRED Modeling Language Documentation.


A FRED model is designed to reflect some aspect of reality relating to people and their interactions. A model can be represented graphically, for example, as a state diagram, or as code in the FRED language. A model is a representation of the conditions, behavior decisions, and impacts that people may experience.


In FRED, agents represent individual people. They have an age, gender, race, and other demographic information associated with them that can be used within the model.


A FRED simulation is the execution of a model with a defined set of parameters, especially the specific location and time-frame. The location determines the population, or set of agents, that participate in the simulation. During a simulation the individual agents experience the conditions, make decisions, and are impacted by the model. The results of a FRED simulation evolve over time based on the actions of the agents in the model.


The FRED Modeling Platform refers to the tools provided to build, execute, and analyze FRED models and simulations. This includes local tools for simulating FRED models on your own machine, as well as cloud-based tools for simulating models in the cloud. Simulations with less than 2 million agents can often be running on a local machine, while our cloud tools can support simulation of large urban areas or even an entire state with many millions of agents in a single simulation. The definition and use of the FRED language is documented in the FRED Modeling Language Documentation.