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Designing for Asynchronous Collaboration

Michael BernsteinComputer-Supported Cooperative Work

4/25/07

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An example

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Original

Edits

Composite

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Original

Edits

Intermediate

Composite

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Design Challenges for Asynchronous Collaboration

• Awareness– Of the document’s history– Of the document’s current status

• Re-syncing– Usability: how to merge the myriad changes into a

useful, meaningful whole?

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Today

• Hill, Hollan, Wroblewski, McCandless. Edit Wear and Read Wear. CHI 1992.

• Edwards, Mynatt. Timewarp: Techniques for Autonomous Collaboration. CHI 1997.

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Edit Wear and Read Wear

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Wear• Permanent evidence of use

[McGrath 1984]

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Computational Wear

• Display part of the accrued history as part of the object

• Edit Wear– What has changed? How much has it changed?

• Read Wear– What has been looked at? How much attention

has it received?

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Wear Scroll Bars

Number of edits

Position in document

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Menu Wear

CHI 1992 Mockup

Microsoft Office 2003 Realization

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Computational Wear and Reflective Conversation

• Reflective Conversation– “Through the unintended effects of action, the

situation talks back. The practitioner, reflecting on this back-talk, may find new meaning in the situation which leads him to a new reframing.” [Schoen, in Hill 1992]

• Read and edit wear bring about reflective conversations with the material– Enhancing awareness of others and self

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Computational Wear and CSCW

• Supports awareness of what other authors are doing and have done– Who is reading a topic? Who is working on what

section?• Invokes social responses rather than enforcing

artificial ones

user ‘carbunkle’ has locked paragraph vs.“Oh, Eric is looking at this section; I’ll leave it alone.”

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Future directions?

• “Proactive wear”: adaptive interfaces• Mao et al. 2000: Visualizing Computational

Wear with Physical Wear

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Timewarp: Techniques for Autonomous Collaboration

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Autonomous Collaboration

• Characterized by:– Asynchronous work on a loosely-shared artifact

(e.g., document example)– Periods of tightly-coupled sharing for integration

• Main problem:– Awareness of current and past efforts amongst

users• Term from [Kolland, Markus 1994]

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It’s about time!

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Parallel Timelines

Update

Split

Merge

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Let’s do the Timewarp again

• Time should be malleable– Can adjust any version of the document, not just

the current one– Adjust the file upstream, propagate it to all

downstream versions (including the present)• Time should be explicit– Visible representation of document timelines

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Awareness

• Visualize overall history of the document– Timeline scrollbar: replay any actions from the past– “Meta-history” viewer: get the gestalt

• Magic Lenses [Bier et al.1993]– Overlay specific awareness items as requested

• Who?• What?

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“Details”

• Detecting and mediating conflicting changes– (see the UIST paper)

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…and others.• Rekimoto, Time-machine computing• Dourish, Lifestreams• Apple Inc., Time machine

http://www.apple.com/macosx/leopard/timemachine.html