Studying the User Task of Information Gathering on the Web by Anwar Alhenshiri Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Dalhousie University Halifax, Nova Scotia March 2013 © Copyright by Anwar Alhenshiri, 2013 DALHOUSIE UNIVERSITY FACULTY OF COMPUTER SCIENCE The undersigned hereby certify that they have read and recommend to the Faculty of Graduate Studies for acceptance a thesis entitled “Studying the User Task of Information Gathering on the Web” by Anwar Alhenshiri in partial fulfilment of the requirements for the degree of Doctor of Philosophy. Dated: March 13, 2013 External Examiner: __________________________ Research Supervisor: __________________________ Examining Committee __________________________ __________________________ Departmental Representative: __________________________ ii DALHOUSIE UNIVERSITY DATE: March 13, 2013 AUTHOR: Anwar Alhenshiri TITLE: Studying the User Task of Information Gathering on the Web DEPARTMENT OR SCHOOL: Faculty of Computer Science DEGREE: PhD CONVOCATION: May YEAR: 2013 Permission is herewith granted to Dalhousie University to circulate and to have copied for non-commercial purposes, at its discretion, the above title upon the request of individuals or institutions. I understand that my thesis will be electronically available to the public. The author reserves other publication rights, and neither the thesis nor extensive extracts from it may be printed or otherwise reproduced without the author’s written permission. The author attests that permission has been obtained for the use of any copyrighted material appearing in the thesis (other than the brief excerpts requiring only proper acknowledgement in scholarly writing), and that all such use is clearly acknowledged. _________________________________ Signature of Author iii DEDICATION This dissertation is dedicated to the first two people I loved, my parents. May my father rest in peace! iv TABLE OF CONTENTS LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES ............................................................................................................ x ABSTRACT ............................................................................................................... xii LIST OF ABBREVIATIONS USED .............................................................................. xiii ACKNOWLEDGEMENTS ............................................................................................. xiv CHAPTER 1 INTRODUCTION .................................................................................. 1 CHAPTER 2 RELATED WORK ................................................................................. 7 2.1. INFORMATION SEEKING MODELS ...................................................................... 7 2.1.1. Ellis’s Model .................................................................................... 7 2.1.2. Marchionini’s Model ........................................................................ 9 2.1.3. Wilson’s Model .............................................................................. 12 2.1.4. Wilson’s Combined Model ............................................................ 13 2.2. MODELS OF USER TASKS ON THE WEB ........................................................... 14 2.2.1. Broder’s Taxonomy ........................................................................ 16 2.2.2. Sellen’s Taxonomy ......................................................................... 17 2.2.3. Rose and Levinson’s Classification ............................................... 19 2.2.4. Kellar’s Framework ........................................................................ 21 2.3. A REVIEW OF THE TASK OF INFORMATION GATHERING ON THE WEB ............. 23 2.4. VISUALIZING, CLUSTERING, RE-FINDING, AND ORGANIZING WEB INFORMATION ............................................................................................................... 24 2.4.1. Visualizing Web Information ......................................................... 25 2.4.2. Clustering Web Information ........................................................... 28 2.4.3. Re-finding Web Information .......................................................... 30 2.4.4. Managing and Organizing Web Information ................................. 32 2.5. SUMMARY ....................................................................................................... 36 CHAPTER 3 INFORMATION GATHERING .......................................................... 37 3.1. SUBTASKS IN THE INFORMATION GATHERING TASK ....................................... 37 3.1.1. Interpreting the Task ...................................................................... 38 3.1.2. Finding Sources of Information on the Web .................................. 38 3.1.3. Finding Information on the Web .................................................... 39 3.1.4. Finding Related Information .......................................................... 39 v 3.1.5. Comparing Information, Reasoning, and Decision Making........... 41 3.1.6. Keeping and Re-finding Information ............................................. 42 3.1.7. Managing and Organizing Information .......................................... 42 3.1.8. Reviewing the Task ........................................................................ 43 3.2. DEFINING THE TASK OF INFORMATION GATHERING ........................................ 44 3.3. THE PROCESS OF INFORMATION GATHERING ON THE WEB ............................. 48 3.4. SUMMARY ....................................................................................................... 49 CHAPTER 4 PRELIMINARY STUDIES .................................................................. 51 4.1. VSE, A VISUAL SEARCH ENGINE FOR IMPROVING HOW USERS GATHER INFORMATION ON THE WEB .......................................................................................... 51 4.1.1. Design and Implementation............................................................ 51 4.1.2. Search and Response ...................................................................... 52 4.1.3. The Interactive Search Interface ..................................................... 52 4.1.4. Research Questions ........................................................................ 54 4.1.5. VSE Evaluation .............................................................................. 54 4.1.6. Study Location and Population ...................................................... 55 4.1.7. Study Design .................................................................................. 55 4.1.8. Study Tasks .................................................................................... 55 4.1.9. Study Methodology ........................................................................ 55 4.1.10. Study Data.................................................................................... 56 4.1.11. Study Results ............................................................................... 56 4.1.12. Study Limitations ......................................................................... 62 4.1.13. Discussion .................................................................................... 62 4.1.14. Conclusion ................................................................................... 63 4.2. VLN, A VISUAL LINK NAVIGATION INTERFACE FOR FINDING INFORMATION WITHIN WEB HIERARCHIES ........................................................................................... 63 4.2.1. Design and Implementation............................................................ 63 4.2.2. Research Questions ........................................................................ 66 4.2.3. VLN Evaluation ............................................................................. 66 4.2.4. Study Location and Population ...................................................... 67 4.2.5. Study Design .................................................................................. 67 4.2.6. Study Tasks .................................................................................... 67 4.2.7. Study Methodology ........................................................................ 68 vi 4.2.8. Study Data ...................................................................................... 68 4.2.9. Study Results .................................................................................. 68 4.2.10. Discussion .................................................................................... 73 4.2.11. Study Limitations ......................................................................... 74 4.2.12. Conclusion ................................................................................... 74 4.3. SUMMARY ....................................................................................................... 74 CHAPTER 5 INVESTIGATING THE TASK OF INFORMATION GATHERING ON THE WEB ............................................................................................................... 76 5.1. RESEARCH STUDY ........................................................................................... 76 5.1.1. Research Questions ........................................................................ 76 5.1.2. Study Design and Population ......................................................... 76 5.1.3. Task Description and Construction