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Modelling Migration: Decisions, Processes and Outcomes

Human migration is uncertain and complex, and some of its distinct features, such as migration routes, can emerge and change very rapidly. Agency of various actors is one key reason for why migration eludes attempts at its theoretical description, explanation and prediction. To address the complexity challenges through simulation models, which would coherently link micro-level decisions with macro-level processes, a coherent model design and construction process is needed. Here, we present such a process alongside its five building blocks: an agent-based simulation of migration route formation, resembling the recent asylum migration to Europe; an evaluation framework for migration data; psychological experiments eliciting decisions under uncertainty; the choice of a programming language and modelling formalisms; and statistical analysis with Bayesian meta-modelling based on Gaussian Process assumptions and experimental design principles. This process allows to identify knowledge advancements that can be achieved through modelling, and to elucidate the remaining knowledge gaps.