@article{ref1,
title="Sampling vehicle kilometers of travel",
journal="Transportation research record",
year="1979",
author="Levinson, Herbert S. and Roark, Adelbert L. and Guhn, J. S.",
volume="728",
number="",
pages="65-72",
abstract="This paper develops sampling procedures for estimating vehicle kilometers of travel on urban streets. It shows how simple and stratified random sampling techniques can be applied to estimate sample-size requirements for estimating freeway, arterial-collector, and local-street vehicle kilometers of travel. The paper also presents and provides ranges in the parameters associated with the variations in traffic volumes in space and time. These estimates are then used as part of a practical, operational procedure.<p />",
language="en",
issn="0361-1981",
doi="",
url="http://dx.doi.org/"
}