@unpublished{brewington:observe,
    author = {Brian Brewington},
    title = {{Ph.D} Thesis Proposal: Optimal Observation with {WWW}
Applications},
    year = {1998},
    school = {Thayer School of Engineering, Dartmouth College},
    copyright = {Brian Brewington},
    group = {agents, actcomm},
    url = {http://agent.cs.dartmouth.edu/papers/brewington:observe.ps.gz},
    abstract = {This thesis proposal deals with optimal observation of large
collections of changing objects. These objects can change at random times, so
we cannot know the state of objects for times at which they are unobserved.
The goal of an observer is to maintain acceptably accurate state estimates
while minimizing observational cost. In the thesis work, our goals are to (1)
create models for this type of system, (2) show how these models can be
empirically constructed by actually observing real systems, and (3) develop
efficient algorithms for the optimal allocation of observation resources
within this framework. An example of this type of optimization arises in the
observation of World Wide Web (WWW) documents by web search engines and
related web software applications. Our initial results include (1) developing
statistical models for such systems; (2) collection of empirical data about
how web documents change; and (3) development of finite-horizon algorithms
for maximizing an index's accuracy. Although the algorithms presented are
intended for optimizing the recency of document indices, they are general
enough to be applied to any dynamic collection of objects. The work is
important and novel in that it takes proper account of the cost of observing,
a concept that is crucial to monitoring problems in many communications
systems.}
}