Expectations and memory in link search

摘要

Strategies in searching a link from a web page can rely either on expectations of prototypical locations or on memories of earlier visits to the page. What is the nature of these expectations, how are locations of web objects remembered, and how do the expectations and memories control search? These questions were investigated in an experiment where, in the experimental group, nine experienced users searched links. To obtain information about expectations, users' eye movements were recorded. Memory for locations of web objects was tested immediately afterwards. In the control group, nine matched users had to guess the locations of web objects without seeing the page. Eye-movement data and control group's guesses both indicated a robust expectation of links residing on the left side of the page. Only the location of task-relevant web objects could be recollected, indicating that deep processing is required for memories to become consciously accessible. A comparison between the experimental group and the control group revealed that what was represented in memory was not an individual link's location but the approximate locations of link panels. We argue that practice-related decreases in reaction time were caused by semantic priming. Roles for the different types of memory in link search are discussed.