@article{ref1,
title="Warrants for left-turn signal phasing",
journal="Transportation research record",
year="1979",
author="Agent, Kenneth R. and Deen, Robert C.",
volume="737",
number="",
pages="1-10",
abstract="Warrants for the installation of left-turn phasing in Kentucky were developed. A review of the literature was conducted, along with a survey of the policies of other states. Field data on delays and conflicts were taken before and after installation of exclusive left-turn signalization. Left-turn delay studies were conducted at intersections that had varying volume conditions. Analysis of the effect on accidents of adding a left-turn phase was made. The relationship between left-turn accidents and conflicts was investigated. Other types of analyses concerning gap acceptance, capacity, and benefit-cost ratios were also performed. It was found that exclusive left-turn phasing significantly reduced left-turn accidents and conflicts. This reduction was offset in part by an increase in rear-end accidents. Left-turn delay was reduced only during periods of heavy traffic flow. Total delay for an intersection increased after installation of left-turn phasing. Warrants were developed dealing with accident experience, delay, volumes, and traffic conflicts.<p />",
language="en",
issn="0361-1981",
doi="",
url="http://dx.doi.org/"
}