@article{ref1,
title="Modeling count data with excess zeroes an empirical application to traffic accidents",
journal="Sociological methods and research",
year="2003",
author="Chin, Hoong Chor and Quddus, Mohammed Abdul",
volume="32",
number="1",
pages="90-116",
abstract="There are many studies in social sciences, such as traffic accident analysis, in which the event counts may be characterized by a large number of zero observations. In this article, a proposed model that takes into account both the zero-count state and the nonzero-count state is used to describe the traffic accident phenomenon. The probability of the zero-count state (p) and the mean number of event counts (µ) in the non-zero-count state may depend on the covariates. Sometimes, p and µ are unrelated, while at other times, p may assume a simple function of µ.In proposing the model, different types of traffic accidents at signalized intersections in Singapore were investigated. The results demonstrate that the zero-altered probability process is an appropriate technique for modeling specific types of accidents in which the data contain many zero counts.<p /><p>Language: en</p>",
language="en",
issn="0049-1241",
doi="10.1177/0049124103253459",
url="http://dx.doi.org/10.1177/0049124103253459"
}