1. WYSIWIS Revised: Early Experiences with Multiuser Interfaces Stefik, Bobrow, Foster, Lanning, and Tatar

2. Terms Colab is an experimental meeting room developed at Xerox PARC in which computers support collaborative processes in face-to-face meetings. –Meeting tools provide operations in terms of visible, manipulable objects WYSIWIS (What You See Is What I See) –In strict WYSIWIS, everyone sees exactly the same image of the written meeting information and can see where everyone is (tele) pointing. Public vs. Private Windows (I.e., multiuser vs. single user windows) 4 dimensions for relaxing strict WYSIWIS –Space Only a subset of the visible objects are wysiwis (e.g, windows and cursors) –Synchronization Allow delays in updating or viewing –Population Only subgroups of meeting share viewing –Congruence Alternate views of same image

3. Case 1: Boardnoter (The humble chalkboard) Provides white board, chalk, eraser, keyboard, and pointer Issue: Display of cursors from multiple users is too distracting Solution: Display only local implements and those used for telepointing Issue: Small grain-size transmission of data is computationally expensive Solution Broadcast changes to information when the user indicates completion or after a reasonable time interval Issue: Meetings often need multiple chalkboard, but there is room to show only one display at a time Solution: Provide multiple visible boards by arranging shrunken ver4sion of them as icons in a stampsheet

4. Case 2: COGNOTER (Collaboration in the organization of ideas) A meeting tool for organizing ideas for a presentation Organizes its meeting process into a sequence of stages: brainstorming, ordering and grouping, evaluation, and outline generation. Problem: Participants needed to fiddle with window sizes and placements too much. –Exacerbated by having a mix of public and private windows Two proposals for organizing displays –Stampsheet –Rooms

5. Stampsheet approach Issue: Screen can be crowded with windows used mainly by other participants Solution: Allow participants to select independently which windows are full scale Issue: When windows are it is not longer possible to assess quickly the locus of activity or which information has changed Solution: Stampsheet icons should actively indicate when info is changing Issue: Identifying recent changes is also important for full-size windows Solution: provide a facility for highlighting recent changes Issue: Subgroups need to cause other group members to attend to a particular item without interfering with activities of other subgroups Solution: Provide telepointers that work only within subgroups

6. Stampsheet (Continued) Issue: Subgroups need to be able to bring information to the attention of a full meeting Solution: Provide both full and subgroup telepointing Issue: Participant wants to join a subgroup but cannot find the stamp corresponding to a subgroup window Solution: label windows and stamps Issue: When new public window is created, putting the window on all displays may disrupt the activities of other subgroups Solution: Automatically display new window on the displays of those participants who have the spawning window at full scale Issue: Public and private windows compete for display space. Adding a new window to the display of subgroup can occlude windows of other participants Solution: Participants can control the placement of all windows are their display

7. Rooms Issue: Screen can be crowded with windows used mainly by other participants Solution: Provide separate rooms for each subgroup. Rooms are connect by doors. Issue: When subgroups in separate rooms, not possible to track overall progress or progress in other rooms Solution: Create an overview room from which one can watch the overall activities of the meeting. Issue: Identifying recent changes is also important when a participant reenters a room. Solution: Provide a facility for highlighting recent changes in a room

8. Rooms (continued) Issue: Subgroups need to cause other group members to attend to a particular item without interfering with the activities of other groups Solution: Provide supgroup pointer that who only within a room Issue: Bringing information to the attention of the full meeting Solution: Provide a full-group telepointer that teleports all participants to the room of interest

9. Comparisons Different approaches to placement of public windows –Stampsheet Place of public windows is privately determined –Rooms Public windows in the same place for everybody Rooms create harder boundaries between subgroups because participants must leave room to visit other subgroups Reconsidering division of items between two sets of ideas being worked on by two different subgroups –Stampsheet Participant just opens relevant windows –Rooms Greater overhead because a participant must either create a new room for the comparison or involve all the other members of one of the subgroups with the extra windows