DiffIE: Changing How You View Changes on the Web DiffIE: Changing How You View Changes on the Web Jaime Teevan, Susan T. Dumais, Daniel J. Liebling, and Richard L. Hughes Microsoft Research

Information Artifacts Change

Digital Dynamics Easy to Capture

Web Dynamics JanuaryFebruaryMarch April May JuneJuly August September Content Changes Number of studies of change [2, 7, 10, 20] Frequency and degree of change characterized Visited pages are more likely to change [2]

Web Dynamics JanuaryFebruaryMarch April May JuneJuly August September Content Changes People Revisit JanuaryFebruaryMarch April May JuneJuly August September People revisit on the Web a lot – Over half of page visits are revisits [2, 22] – Over a third of searches are for re-finding [23] Revisitation relates to change – 66% of revisits are to changed pages [2] – 20% of the content changes [2] – Revisiting often motivated by change [2, 15] – Change interferes with revisiting [21, 23]

Web Dynamics JanuaryFebruaryMarch April May JuneJuly August September Content Changes People Revisit JanuaryFebruaryMarch April May JuneJuly August September Today’s Browse and Search Experiences Ignores …

DiffIE Changes to page since your last visit DiffIE toolbar

Systems That Expose Web Change Historical access to pages – Internet Archives (archive.org) Subscription to change – RSS, Web slices – Monitoring support [15] In-situ awareness of change – symbols – Dynamo [3], Difference Engine [9], WebCQ [17]

Interesting Features of DiffIE Always on In-situ New to you Non-intrusive

How DiffIE works How we studied DiffIE How DiffIE is used Conclusions and future work Overview

HOW DiffIE WORKS

DiffIE DiffIE Architecture Web Cache Toolbar ComponentComparison Component IE Client Machine

Toolbar Compare to older versions Status message Feedback buttons See previous version Hide highlighting

Cache Web page representation – Leaf nodes in DOM: Hash of text – Parent nodes: Hash of children, appended Cache multiple versions of pages visited Small footprint (50KB) – Exact duplicates stored as pointer files – Cap count (only 6% of pages visited >5 times) Privacy preserving

Comparison Component Change Deletion Addition Movement A A B B D D C C E E F F A A B B C C D D E E E E D D Node has fewer children Node has more children, child new Node has new child, child present Node has same children, child changes

Comparison Component Change Deletion Addition Movement Highlighted: Additions, changes Not highlighted: Moves, deletions Node has fewer children Node has more children, child new Node has new child, child present Node has same children, child changes

STUDYING DiffIE

Interesting Features of DiffIE Always on In-situ New to you Background

Methods for Studying DiffIE Large scale demonstration Feedback buttons Experience interview – 11 people (5 female, 6 male) – Interviewed after extended DiffIE use (2+ weeks) – Asked about general experience – Revisited 10 pages (half from today/yesterday)

HOW DiffIE IS USED

Expected New Content

Monitor

Unexpected Important Content

Serendipitous Encounters

Understand Page Dynamics

Attend to Activity

Edit

Attend to Activity Edit Understand Page Dynamics Serendipitous Encounter Unexpected Important Content Expected New Content Monitor Expected Unexpected

Monitor

Find Expected New Content

CONCLUSION AND FUTURE WORK

Web dynamics important – Change and revisitation common and related DiffIE exposes change upon revisitation – Caches representations of visited pages – Additions and changes identified and highlighted DiffIE used in unexpected ways – Some Web content becomes more valuable – Not as useful for sites designed around change Summary

Next Steps Additional ways to display change – Other interfaces: fade, moves/deletes, differences – Just show change: mobile, mash ups – Allow user to subscribe to change Decide when and what to highlight – Important v. unimportant changes (e.g., ads) – Provide access to unseen change API exposing change

Thank you. DiffIE Teevan, J., S. T. Dumais, D. J. Liebling, and R. Hughes. Changing How People View Changes on the Web. UIST Change Adar, E., J. Teevan, S. T. Dumais, and J. L. Elsas. The Web changes everything: Understanding the dynamics of Web Content. WSDM 2009 (Best Student Paper). Revisitation Adar, E., J. Teevan, and S. T. Dumais. Large scale analysis of Web revisitation patterns. CHI 2008 (Best Paper). Relationship Adar, E., J. Teevan, and S. T. Dumais. Resonance on the Web: Web dynamics and revisitation patterns. CHI Jaime Teevan

EXTRA SLIDES

DiffIE Received Positively Feedback buttons – 51% of unsolicited feedback positive (v %) Experience interview (conditioned on change) – 61% positive – 18% neutral – 21% negative

Reported Experience with DiffIE

Performance Highlighting shown on page load event Appears 10s to 100s of milliseconds after load Does not interfere with browsing experience Often appears after interaction begins Notification of delay important