CBSD Model for the SEA

This repository contains a simulation model for the spread of Cassava Mosaic Disease (CMD) in Southeast Asia, focusing on Thailand, Cambodia, Laos, and Vietnam. It includes scripts to construct input matrices, simulate disease dynamics over a 15-year horizon, analyze propagation trends, and generate maps for each cultivation cycle. Additionally, it integrates the economic scenarios generated by the IMPACT model.
Methodology:This methodology utilizes R (version 4.3.1) to simulate Cassava Mosaic Disease (CMD) spread across SEA. Transmission probabilities between regions are modeled based on geographic distances using the inverse power law. The model accounts for two transmission pathways: land-based seed transportation and whitefly vector transmission. Finally, the model's 15-year projections are optimized by calibrating against PestDisplace occurrence data (2019–2022) using Root Mean Square Error (RMSE) as the accuracy metric. Furthermore, the framework incorporates various economic scenarios generated by the IMPACT model to project future disease impact.