GEPOC ABM, Generic Population Concept -- Agent-Based Model, Version 2.2

The Generic Population Concept - Agent-Based Model, henceforth short, GEPOC ABM, is one of the models within GEPOC, a generic concept to model a country's population and its dynamics using causal modelling approaches. The model is well established and had already proven its worth in various use cases from evaluation of MMR vaccination rates to SARS-CoV-2 epidemics modelling. In this work we will reproducibly specify the base model, to be specific, version 2.2 of it, and several extensions. The base model GEPOC ABM depicts the population of a country with the features sex and age. It uses a co-simulation-inspired time-update, where person-level discrete-event simulators are synchronised by a simulation layer at macro-steps, making the approach amenable to parallelization. A core design choice is structuring person agents around the life-year rather than the calendar year; accordingly, each agent schedules demographic events annually on their birthday. To expand the model's capabilities beyond basic demographic features, GEPOC ABM Geography adds a residence feature in the form of geographical coordinates. Further extensions include GEPOC ABM IM, which adds internal migration processes in three variants, and GEPOC ABM CL, which models locations where agents may have contacts with each other. In this definition we solely specify the conceptual models and do not go into any details with respect to implementation or gathering/processing of parametrisation data.