Comparison of the implementation of a flood evacuation model on two different geographical agent-based platforms: Netlogo and Gama.

Abstract Agent-based simulation has gained interest in geography in recent years. Several platforms facilitate the development of spatially focused multi-agent models. However, each platform and language has its own specificities, and the same conceptual model can lead to different behaviors and results depending on the type of implementation used. Reproducing the same model on multiple platforms is the best way to test its reliability, while eliminating biases related to implementation. This "good practice" is still very rare, yet essential for making a more robust model. In this paper we present the implementation of the same conceptual model on two distinct platforms (Netlogo and Gama). Despite some overall similarities in the results, differences are observed in the outputs and functioning. These variabilities come from various factors, but a significant proportion results from the different ways of integrating geographical data, which differ between the two platforms. To highlight this geographical aspect, we use a conceptual model dealing with a flood evacuation.