  Writing is a complex non-linear process that begins with a mental model of
intent, and progresses through an outline of ideas, to words on paper (and
their subsequent refinement). Despite past research in understanding writing,
Web-scale consumer and enterprise collaborative digital writing environments
are yet to greatly benefit from intelligent systems that understand the stages
of document evolution, providing opportune assistance based on authors'
situated actions and context. In this paper, we present three studies that
explore temporal stages of document authoring. We first survey information
workers at a large technology company about their writing habits and
preferences, concluding that writers do in fact conceptually progress through
several distinct phases while authoring documents. We also explore,
qualitatively, how writing stages are linked to document lifespan. We
supplement these qualitative findings with an analysis of the longitudinal user
interaction logs of a popular digital writing platform over several million
documents. Finally, as a first step towards facilitating an intelligent digital
writing assistant, we conduct a preliminary investigation into the utility of
user interaction log data for predicting the temporal stage of a document. Our
results support the benefit of tools tailored to writing stages, identify
primary tasks associated with these stages, and show that it is possible to
predict stages from anonymous interaction logs. Together, these results argue
for the benefit and feasibility of more tailored digital writing assistance.
