SNIF-ACT: A Cognitive Model of User Navigation on the World Wide Web

reportActive / Technical Report | Accession Number: ADA462156 | Open PDF

Abstract:

We describe the development of a computational cognitive model that explains navigation behavior on the World Wide Web WWW. The model, called SNIF-ACT Scent-based Navigation and Information Foraging in the ACT cognitive architecture, is motivated by Information Foraging Theory IFT, which quantifies the perceived relevance of a Web link to a user goal by a spreading activation mechanism. The model assumes that users evaluate links on a Web page sequentially, and decide to click on a link or to go back to the previous page by a Bayesian satisficing model BSM that adaptively evaluates and selects actions based on a combination of previous and current assessments of the relevance of link texts to information goals. The model was tested against data collected from novice users engaged in unfamiliar information-seeking tasks. SNIF-ACT 1.0 utilizes the measure of utility, called information scent, derived from IFT to predict rankings of links on different Web pages. The model was tested against a detailed set of protocol data collected from eight subjects as they engaged in two information-seeking tasks using the WWW. The model provided a good match to subjects link selections and decisions to leave a Web site, and thus provided support for the use of information scent as a psychological measure of the perceived relevance of link text to information goals. In SNIF-ACT 2.0, we include an adaptive link selection mechanism that sequentially evaluates links on a Web page according to their position. The mechanism was derived based on a rational analysis of link selection on a Web page. The mechanism allowed the model to dynamically update the evaluation of actions e.g., to follow a link or leave a Web site based on sequential assessments of link texts on a Web page, and to decide when to leave a page based on experiences with previous pages. SNIF-ACT 2.0 was validated on a data set obtained from 74 subjects. Monte Carlo simulations of the model showed that SNIF-ACT 2

Author(s):
Fu, Wai-tat ; Pirolli, Peter
Author Organization(s):
ILLINOIS UNIV AT URBANA-CHAMPAIGN SAVOY AVIATION HUMAN FACTORS DIVISION
Supplementary Note:
Sponsored in part by Advanced Research and Development Activity. Prepared in cooperation with Palo Alto Research Center. Submitted to Human-Computer Interaction. The original document contains color images. DOI: 10.21236/ADA462156
Pagination:
0068

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release
Distribution Statement:
Approved For Public Release; Distribution Is Unlimited.

RECORD

Collection: TR
Identifying Numbers
Contract/Grant Number(s):
N00014-96-C-0097, MDA904-03-C-0404
Monitor Series:
ONR
 Subject Terms
Joint Capability Areas:
JCA_5_Command and Control; JCA_5.3_Planning; JCA_4.6_Engineering; JCA_5.5.2_Task; JCA_5.5_Direct; JCA_4.6.1_General Engineering; JCA_5.3.3_Develop Strategy; JCA_5.3.2_Apply Situational Understanding; JCA_5.2.2_Develop Knowledge and Situational Awareness; JCA_5.2_Understand; JCA_2.1_Planning and Direction; JCA_2.1.2_Develop Strategies; JCA_1.2.5_Lessons Learned; JCA_5.4_Decide; JCA_1.2.3_Educating; JCA_1.2.7_Experimentation; JCA_1.2.6_Concepts
Modernization Areas:
Autonomy
Communities of Interest:
Biomedical
Descriptor(s):
*MATHEMATICAL MODELS, *NAVIGATION, *INTERNET, COGNITION, INTERNET BROWSERS, USER NEEDS, BEHAVIOR
Field(s)/Group(s):
Information Science, Psychology, Computer Programming and Software, Human Factors Engineering and Man Machine Systems
Keyword(s):
*COGNITIVE MODELS, *SNIF ACT(SCENT BASED NAVIGATION AND INFORMATION FORAGING IN THE ACT ARCHITECTURE), *INFORMATION SCENT, *INFORMATION SEEKING, IFT(INFORMATION FORAGING THEORY), BSM(BAYESIAN SATISFICING MODEL), RATIONAL ANALYSIS, SPREADING ACTIVATION, HUMAN COMPUTER INTERACTION
Report Date:
2007 Jan 03
Creation Date:
2007 Feb 28