Human Computer Interaction

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All computer systems, single user or multi-user, interact with the work-groups and organizations in which they are used
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Need to understand normal human-human communication
 face-to-face communication involves eyes, face and body
 conversation can be analysed to establish its detailed structure

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This can then be applied to text-based conversation, which has
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 reduced feedback for confirmation less context to disambiguate utterances slower pace of interaction but is more easily reviewed
Group working is more complex than that of a single person
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 influenced by the physical environment experiments are more difficult to control and record field studies must take into account the social situation

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Humans are inherently social creatures
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We live together, work together, learn together, play together, etc.
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Therefore, we need to develop interactive systems that support and extend these kinds of social interactions
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Communication and collaboration

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Most primitive and most subtle form of communication
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Often seen as the paradigm for computer mediated communication

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Transfer effects
 carry expectations into electronic media
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People are adaptable – eg “over”
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But also expect they can use existing norms (eg: cultural)
 sometimes with disastrous results
 may interpret failure as rudeness of colleague
 e.g., personal space video may destroy mutual impression of distance happily the “glass wall” effect helps

 to convey interest and establish social presence
 video may spoil direct eye contact
 but poor quality video better than audio only
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Establishing context – focus of the conversation

 much of our communication is through our bodies
 gesture (and eye gaze) used for deictic reference
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Deictic – “directly pointing out” (oed.com)
 head and shoulders video loses this
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So: close focus for eye contact or wide focus for body language?

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Alison:
Do you fancy that film, err
[1]
-`The Green' – um
[2]
– it starts at eight.
Brian:
Great!
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Not just the words!
Back channel responses from Brian at 1 and 2
 quizzical at 1
 affirmative at 2
Back channels include:
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 nods and grimaces shrugs of the shoulders grunts and raised eyebrows
Utterance begins vague then sharpens up just enough

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Restricting media restricts back channels
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Video … loss of body language
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Audio … loss of facial expression
Half Duplex … lose most voice back channel responses
Text Based … nothing left!
Back channels used for turn-taking:
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Speaker offers the floor (fraction of a second gap)
Listener requests the floor (facial expression, small noise)
Grunts, ‘um's and ‘ah's, can be used by the:
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 listener to claim the floor speaker to hold the floor
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But often too quiet for half-duplex channels
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Trans-continental conferences - special problems
 lag can exceed the turn taking gap
 leads to a monologue!

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Alison: Do you fancy that film
Brian: the uh
(500 ms) with the black cat –”The Green whatsit”
Alison: yeah, go at uh
(looks at watch 1.2 s) twenty to ?
Brian: sure
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Smallest unit is the utterance
Turn taking … utterances usually alternate

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Simplest structure - adjacency pair
Adjacency pairs may nest;
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Brian: Do you want some gateau? (X)
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Alison: is it very fattening? (Y)
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Brian: yes, very (Y)
Alison: and lots of chocolate? (Z)
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Brian: masses (Z)
Alison: I'll have a big slice then. (X)
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Structure is: B-x , A-y, B-y, A-z, B-z , A-x
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Inner pairs often for clarification
But, simple pairing is not always possible or useful

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Utterances are highly ambiguous
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We use context to disambiguate
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Brian: (points) that post is leaning a bit
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Alison: that's the one you put in

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Two types of context:
 external context
 reference to the environment
 e.g., Brian's “ that ” = the thing pointed to [deictic reference]
 internal context
 reference to the previous conversation
 e.g., Alison's “ that ” = the last thing spoken of

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Often contextual utterances involve indexicals:
 that, this, he, she, it
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These may be used for internal or external context
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Also descriptive phrases may be used:
 external: “the corner post is leaning a bit”
 internal: “the post you mentioned”

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Resolving context depends on meaning
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 participants must share meaning so must have shared knowledge
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Conversation constantly negotiates meaning
 process called grounding
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Alison: So, you turn right beside the river.
Brian: past the pub.
Alison: yeah -
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Each utterance is assumed to be:
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relevant - furthers the current topic
helpful - comprehensible to listener

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Context resolved relative to current dialogue focus
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Alison: Oh, look at your roses –
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Brian: mmm, but I've had trouble with green fly.
Alison: they're the symbol of the English summer.
Brian: green fly?
Alison: no roses silly!
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Tracing topics is one way to analyse conversation.
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Alison begins - topic is roses
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Brian shifts topic to green fly
Alison misses shift in focus = breakdown

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You can classify utterances by the task they perform in the conversation
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Substantive
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– directly relevant to the development of the conversation
Annotative
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– points of clarification, elaboration etc
Procedural
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– talking about the process of collaboration itself

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Alison is giving Brian directions, using a whiteboard
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Alison: you go along this road until you get to the river
Brian: do you stop before the river or after you cross it?
Alison: before
Brian: draw the river in blue and the road in black
Alison: So, you turn right beside the river
Brian: past the pub
Alison: yeah … is there another black pen? This one is running dry.
NB: The final utterance is “procedural technical” and indicates that the system has become apparent to the participants substantive annotative annotative procedural substantive substantive procedural

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Breakdown happens at all levels:
 topic, indexicals, gesture
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Breakdowns are frequent, but:
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redundancy makes detection easy
(Brian cannot interpret “ they're the symbol of the English summer ”)
 people very good at repair
(Brain and Alison quickly restore shared focus)
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Electronic media may lose some redundancy
= breakdown more severe

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Alison: Isn’t that beautiful
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Points to a large male deer (stag) standing next to a tree
Brian: the symmetry of the branches
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He thinks she pointed to the tree
Alison: how some people can dislike them I cannot understand!
Brian: Yes – the park rangers should shoot all those damn deer before they kill the trees off for good!
Alison: (silence)
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NOTE: Brians reference to symmetrical branches MAY have sounded to Alison like a reference to the stag’s antlers!

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A specific form of conversational analysis
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Utterances characterised by what they do, they’re acts
 e.g., “I'm hungry”
 propositional meaning – hunger
 intended effect – “get me some food”
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Classic example: “I now pronounce you man & wife”

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Basic conversational acts (illocutionary points):
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Promises
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Requests
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Declarations
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Assertions
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Counters
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Reneges
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Withdrawals

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Generic patterns of acts can be identified:
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Conversation for action (CfA)
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Seeks to obtain a specific request
Conversation for clarification (CfC)
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Usually embedded in CfA - to clarify the requested action
Conversation for possibilities (CfP)
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Looking towards future actions
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Conversation for Orientation (CfO)
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Building a shared understanding

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Circles represent ‘states’ in the conversation
Arcs represent utterances (speech acts)
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Simplest route 1-2-3-4-5:
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Alison: have you got the market survey on chocolate?
[request]
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Brian: sure [promise]
Brian: there you are [assert]
Alison: thanks [declare]
More complex routes possible, e.g., 1-2-6-3
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Alison: have you got – [request]
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Brian: I've only got the summary figures [counter]
Alison: that'll do [accept]

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Most common media for asynchronous groupware
 exceptions: voice mail, answer phone
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Familiar medium, similar to paper letters
 but, electronic text may act as speech substitute!

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Types of electronic text:
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Discrete: directed messages, no structure
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Linear: messages added (in temporal order)
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Non-Linear: hypertext linkages
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Spatial: two dimensional arrangement

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Most obvious loss, no facial expression or body language
 weak back-channels, so it is difficult to convey:
 affective state - happy, sad, angry humorous
 illocutionary force - urgent, important, deferential
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Participants compensate by flaming and smilies ;-)

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Establishing common ground depends on grounding constraints
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Co-Temporality: - instant feedthrough
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Simultaneity: - speaking together
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Sequence: - utterances ordered

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These constraints are often weaker in text based communication than in face-to-face conversation
 e.g., loss of sequence in linear text: network delays or coarse granularity = overlap

1.
2.
3.
4.
5.
6.
Bethan : how many should be in the group?
Rowena : maybe this could be one of the 4 strongest reasons
Rowena : please clarify what you mean
Bethan : I agree
Rowena : hang on
Rowena : Bethan what did you mean?
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Message pairs 1&2 and 3&4 composed simultaneously
 i.e., lack of common experience
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Rowena : 2 1 3 4 5 6
Bethan : 1 2 4 3 5 6
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Above shows breakdown of turn-taking result of poor back channels

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Recall context disambiguation was essential for
Text loses external context, hence deixis
(cf: deictic) linking to shared
objects can help
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1. Alison : Brian's got some lovely roses
2. Brian : I'm afraid they're covered in green fly
3. Clarise : I've seen them, they're beautiful
Both (2) and (3) are responses to (1)
 but the transcript suggests green fly are beautiful
Hypertext can maintain ‘parallel’ conversations

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Pace of conversation - the rate of turn taking
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face-to-face - every few seconds
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telephone - half a minute
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email - hours or days
 face-to-face conversation is highly interactive
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If initial utterance is vague feedback gives cues for comprehension
 lower pace = less feedback = less interactive

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Coping strategies attempt to increase granularity:
 eagerness - looking ahead in the conversation game
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Brian : Like a cup of tea? Milk or lemon?
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multiplexing - several topics in one utterance
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Alison : No thanks. I love your roses.

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Conversation is like a game
Linear text follows one path through it
Participants choose the path by their utterances
Hypertext can follow several paths at once

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Workgroups constantly change:
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 in structure in size
Several groupware systems have explicit roles
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But roles depend on context and time
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 e.g., M.D. down a mine is under the authority of the foreman e.g., a General can be under a Private during an Int. Briefing and may not reflect duties
 e.g., subject of biography, author, but now writer

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Social structure may change: democratic, autocratic, and group may fragment into sub-groups
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Groupware systems rarely achieve this flexibility
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Groups also change in composition
 new members must be able to ‘catch up’

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Face-to-face working radically affected by layout of workplace
 e.g., meeting rooms:
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 recessed terminals reduce visual impact inward facing to encourage eye contact different social-power positions
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Traditional cognitive psychology is all in the head

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Distributed cognition suggests we look to the world
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Thinking takes place in interaction with other people and the physical environment
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Implications for group work:
 importance of mediating representations
 group knowledge greater than sum of parts
 design focus on external representation

“…a generic term which combines the understanding of the way people work in groups with the enabling technologies of computer networking, and associated hardware, software, services and techniques .” (Wilson, 1991)
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Any work that is being done between two or more individual where the collaborative nature of the work is supported by computer technology

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Paul Cashman and Irene Grief (1980s)
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Workshop focusing on development of computer systems to support people in their work activities
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A gathering of people from various disciplines
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Shared an interest in how people work
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Understand how technology could support people’s work

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The term "computer-supported cooperative work“ coined to describe this shared interest
First open CSCW conference in 1986 in Austin,
Texas with 300 people attending
Began as an effort by technologists to learn from economists, social psychologists, anthropologists, organizational theorists, educators, and anyone else who could shed light on group activity

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Build tools that support better communication
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E-mail, computer conferencing, voice messaging, Electronic
Meeting Systems (EMS)
Build tools that support better sharing of work tasks, activities and processes
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Remote file sharing, shared drawing and editing tools, shared whiteboards
Determine how to effectively build interfaces that support group communication and sharing
Study existing workgroup collaboration in order to determine how to best support it with technology

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Multidisciplinary
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Software design, organisational behaviour, psychology, communication theory, anthropology, etc.
Key issues
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Group awareness
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Multi-user interfaces
Concurrency control
Group communication and coordination
Shared information space
Focus is on how groups work and how technology can help them work better
Field of study that deals with the design, adoption and use of groupware and issues surrounding the use of groupware

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Groupware is a term for applications written to support the collaboration of several users.
Groupware can support different activities:
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 direct interpersonal communication ideas generation and decision making sharing computer objects.
It can be classified in several ways:
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 by where and when it happens by the sort of information shared
 by the aspects of cooperations supported
Implementing groupware is more difficult than single-user applications:
 because of network delays
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 because there are so many components to go wrong because graphical toolkits assume a single user

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Rethinking business processes and functions because
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People no longer need to work in the same place expertise
The cost of employee communication is significantly lowered
Getting the status of work in progress is easier

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Electronic Mail
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Supports the asynchronous communication of individuals
Media Spaces
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Videoconferencing with computer added features
Video switching to set up subgroups of meeting participants and add cooperative features to the video exchange
Electronic Meetings
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Electronic meeting rooms
Desktop video conferencing
Electronic Whiteboards
Newsgroups
Chat Systems
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Electronic Calendar
Management Systems
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Shared Calendar Systems
Helps group members plan meetings and share availability information
Shared calendar systems tell employees how busy someone is, who they are working with, what projects they are working on
Worksharing Systems
Work Monitoring Systems
Decision Support Systems
Workflow Systems
Multi-player Games

Large Television
Two Rear Projection Screens
Terminals embedded in Table
Conference
Table
Pull out keyboards
Capture Lab
SAMM
Terminals

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Advantages?
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Disadvantages?

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One of the earliest technological innovations
Numerous attempts by companies to introduce videophones
But failed each time…
Why??

Classify groupware by:
when the participants are working, at the same time or not
where the participants are working, at the same place or not same place different place
Common names for axes: time: synchronous/asynchronous place: co-located/remote same time different time

same place different place same time face-to-face conversation telephone different time post-it note letter

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Involves understanding groups and how people behave in groups
Requires special consideration
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Differences between and within groups
Homogeneity of users
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Types of cooperation and collaboration
Key decision makers
Stage of group development
Dynamic nature of groups
Adoption by group

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Usability testing is often significantly more difficult with groupware than with single-user systems.
Windows 3000

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Adoption and acceptance
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Critical mass of users
Avoiding abuse
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Violations of social protocol
Privacy
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Desire to share information
Identification and accountability
Redistribution of power
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E.g. meetings
HCI design issues????

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Many of today’s CSCW systems have been failures
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Why do you think this is so?
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What do you think the major causes of these failures are?
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What do you think can be done to overcome these failures?
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Examples of successful systems?