Trajectories of Search - Mapping Scientific Frontiers: The Quest for Knowledge Visualization - page 147

individual page has received. The home page is the node in the center, and the lines
linked to this represent navigation paths. Navigation issues can be quickly identified,
as can the effect of content changes.

4.1.3 Information Foraging

Searching for information is in many ways like how human beings and animals
hunt for food. Research in biological evolution and optimal foraging identifies some
of the most profound factors that may influence our course of action. Whenever
possible, we prefer to minimize the consumption of our energy in searching for
information. We may also consider reducing other forms of cost. The bottom line
is that we want to maximize the returns by giving away the minimum amount of
resources. The perceived risk and expected gains will affect where we search and
how long we keep searching in the same area. A theory adapted from anthropology,
the optimal information foraging theory (Pirolli and Card 1995 ), can explain why
this type of information can be useful.
Sandstrom ( 1999 ) analyzed scholars' information searching behavior as if they
were hunting for food based on the optimal foraging theory developed in anthropol-
ogy. She focused on author co-citation relationships as a means of tracing scholars in
their information seeking. Sandstrom derived a novelty-redundancy continuum on
which information foragers gauged the costs and benefits of their course of search.
She found three types of center-periphery zones in the mind map of scholars: one's
home zone, core groupings for others and the rest of clusters of scholars.
Sandstrom's study showed that scholars' searching and handling mechanisms
varied by zone, and the optimal foraging theory does explain the variations.
For example, regular reading, browsing, or relatively solitary information seeking
activities often yielded resources belonging mostly to the peripheral zones of
scholars' information environments. Peripheral resources tended to be first-time
references and previously unfamiliar to citing authors, whereas core resources
emerged from routine monitoring of key sources and the cited authors are very
familiar with such resources.
Sandstrom's work draws our attention from the strongest and most salient
intellectual links in traditional author co-citation analysis to the weak bibliographic
connections and less salient intellectual links. Weak links that could lead to the
establishment of an overlooked connection between two specialties are particularly
significant for information foragers and scholars.
In order to understand users' navigation strategies in information foraging,
the profitability of a given document can be defined according to this cost-effect
principle. For example, one can estimate the profitability with the proportion of
relevant documents in a specific area of an information space divided by the
time it will take to read all the documents within this area. In their study of the
Scatter/Gatherer system, Pirolli and Card found that even a much simplified model
of information foraging shows how users' search strategies can be influenced. For