Citation

Quandt RE. Accid. Anal. Prev. 1974; 6(2): 115-123.

Copyright

(Copyright © 1974, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The paper examines hijackings of U.S. registered aircraft since 1968. After some summary characterizations of the series of hijackings, the paper tests the null hypothesis that they represent a homogeneous Poisson process. Using the Durbin-Knott decomposition of the Cramer--von Mises statistic, this hypothesis is rejected. The paper further investigates whether formulating the model as a nonhomogeneous Poisson process represents a significant improvement over the assumption of homogeneity. This question is answered in the affirmative. The major conclusion of the paper, of practical significance, is that hijackings are not independent of one another and security precautions may need to be intensified in periods following a hijacking.