  Temporal information conveyed by language describes how the world around us
changes through time. Events, durations and times are all temporal elements
that can be viewed as intervals. These intervals are sometimes temporally
related in text. Automatically determining the nature of such relations is a
complex and unsolved problem. Some words can act as "signals" which suggest a
temporal ordering between intervals. In this paper, we use these signal words
to improve the accuracy of a recent approach to classification of temporal
links.
