Information Foraging: Scent, Patches, and Diet

Peter Pirolli and Stuart Card's information foraging theory compares information-seeking to animals foraging for food. People follow information scent, cues like link text, headings, and titles, to judge whether a path is likely to lead somewhere valuable, the way a forager senses they're getting "hotter" or "colder." An information patch is a cluster of valuable information, a section of a site, a document, a topic cluster. Foragers stay within a patch as long as it remains productive, then move to another once it's exhausted. Their information diet is the pattern of what they choose to pursue versus what they ignore, weighing expected value against the cost of pursuing it.

When scent is strong, people navigate confidently and find what they need. When scent is weak or absent, people either guess, effectively performing a random walk, or give up entirely. Strengthening scent means making the value of a path visible before the user has to commit to following it.

Weak information scent doesn't just slow people down, it makes them stop trusting their own judgment about where to click next.

Exercise

The scenario: A user is browsing a university's course catalog trying to find an introductory statistics course that fits her schedule. She clicks a link labeled "Mathematics," which opens a long list of course codes, MATH 2210, MATH 3105, and so on, with no course titles or descriptions visible in the list. She has to click into each one individually to find out what it covers or when it meets.

After opening four courses and finding none of them are introductory statistics, she leaves the site.

1. At what point does her information scent break down?
2. Which part of Pirolli and Card's model does this failure most directly represent?