United, we stand: Combining cross-governmental data resources to refine border activities

More than 16 million air passengers arrive in international Australian airports every year. The overwhelming majority of these passengers are not carrying any goods of biosecurity concern. The Australian Department of Agriculture is responsible for intervening at the border to intercept regulated pests. Intervention is risk based: at airports, for example, risk assessment officers determine whether a passenger should undergo further intervention by interview and evaluating the incoming passenger card (IPC), both of which are undertaken in situ. Pre-arrival access to passenger clearance data, which is collected by the Australian Customs and Border Protection Service, may provide more timely and more detailed information that can be used to plan for and prescribe further action. This paper presents an analysis of the combination of biosecurity inspection records with ACBPS clearance records, for Australian air passengers arriving between 2010 and 2013. Decision trees with gradient boosting were used to predict the probability of carriage of biosecurity risk material, using risk factors identified from passenger records. Initial modelling based on training data has produced very promising results, achieving sensitivity and specificity of 73% and 80%, respectively, for prediction of test data under inspection of about 25% of the highest-risk passengers. We discuss the implications of these results for timely and accurate border biosecurity intervention, and the challenges and benefits of merging datasets from different government bodies.