The Use of Proximal Information
Scent to Forage for Distal Content
on the World Wide Web
The legacy of the Enlightenment is the belief that entirely on our own we can know, and in
knowing, understand, and in understanding, choose wisely.… Thanks to science and
technology, access to factual knowledge of all kinds is rising exponentially while dropping in
unit cost.… We are drowning in information, while starving for wisdom.
—E. O. Wilson (1998)
Information foraging theory addresses how people will adaptively shape their behavior to their information environments and how information environments can best be shaped to people. It is a psychological theory explicitly formulated to deal with the analysis of adaptation (good designs) and explicitly formulated to deal with how external content is used to gain valuable knowledge. This symmetrical focus on users and their information system environments has been inspired in many ways by methods and concepts championed in Brunswik's (1952) probabilistic functionalism. This chapter summarizes information foraging research on use of the World Wide Web (hereafter, the Web). This research involves concepts that are akin to ones developed by Brunswik, including the use of representative design, in which realistic Web tasks are studied, a variant of a lens model of how people judge the relevance of navigation cues on the Web, and the use of an idiographic-statistical approach to model aspects of human cognition.
The particular focus of this chapter will be on a psychological theory of information scent (Pirolli, 1997, 2003; Pirolli & Card, 1999) that is embedded in a broader model (Pirolli & Fu, 2003) of in
formation foraging on the Web. The notion of information scent also has been used in developing models of people seeking information in documentclustering browsers (Pirolli, 1997) and highly interactive information visualizations (Pirolli, Card, & Van Der Wege, 2003). Information scent refers to the cues used by information foragers to make judgments related to the selection of information sources to pursue and consume. These cues include such items as Web links or bibliographic citations that provide users with concise information about content that is not immediately available. The information scent cues play an important role in guiding users to the information they seek; they also play a role in providing users with an overall sense of the contents of collections. The purpose of this chapter is to present a theoretical account of information scent that supports the development of models of navigation choice.
Information foraging theory is an example of a recent flourish of theories in adaptationist psychology that draw on evolutionary-ecological theory in biology (e.g., Anderson, 1990; Cosmides, Tooby, & Barow, 1992; Gigerenzer, 2000; Glimcher, 2003). The framework of adaptationist psychology involves the analysis of the structure of the environments faced by people and analysis of the design (or