The Impact of Post‐9/11 Airport Security Measures on the Demand for Air Travel
研究了9/11后美国机场行李安检和旅客安检联邦化对航空旅行需求的影响，发现行李安检使旅客量下降约6%，而旅客安检联邦化影响不大。
We examine the impact of two post‐9/11 airport security measures—baggage screening and federalization of passenger screening—on demand for air travel in the United States. Exploiting the phased introduction of security measures across airports, we find that baggage screening reduced passenger volume by about 6 percent on all flights and by about 9 percent on flights departing from the nation’s 50 busiest airports. In contrast, federalizing passenger screening had little effect on passenger volume. We provide evidence that the reduction in demand was an unintended consequence of baggage screening and not the result of contemporaneous price changes, airport‐specific shocks, schedule changes, or other factors. This decline in air travel had a substantial cost. Back‐of‐the‐envelope calculations indicate that the airline industry lost about $1.1 billion because of the decline, which is 11 percent of the loss attributed directly to 9/11.