This study uses an intervention model to look at the impact of the September 11, 2001 terrorist attack on air transport passenger demand in the US. The result showed that both domestic and international air traffic was significantly impacted for I and 2 months, respectively. The impact pattern was thus abrupt and temporary, instead of gradual and permanent. The approach also provides better forecasts than the seasonal ARIMA benchmark. (c) 2005 Elsevier Ltd. All rights reserved.
