CollaborationQuality of Service

(Shneiderman and Plaisant Chs. 9 and 10,also, Preece et al. Ch 4 and Dix et al. Ch. 13 and 14)

from http://wps.aw.com/aw_shneider_dtui_10, 11

Preece site

Notes

• Shoot for ~1/2 hours• Good about human conversation elements – and

often lost in electronic communication• Need paper vs. screen (if no where else)• Need response time: <100 ms “instantaneous”,

etc. – Tie to “directness” of direct manipulation– Graphic manip – critical– Web is better though of (w/long latency) as

“information repository• Cut/streamline redundancy of “time/space matrix• Cut/better various pieces of unconnected crap

– Maybe find some contemporary systems

Overview

• Types of collaborative interfaces

• About human “conversation– Background for collaboration – from Preece and Dix

• Collaborative systems– Four types and examples

• “Quality of service” – a term from networks– Effect of system parameters …

Collaboration and Social MediaShneiderman and “terminology”

• “Collaboration” typically more “(work) task oriented”, but malleable

Collaboration and Cooperation

• “Computer Supported Collaborative Work” - CSCW– HCI literature

• Goals of cooperation (Shneiderman):– Focused partnerships– Lecture or demonstration– Conference– Structured word processes– Meeting and decision support– Electronic commerce– Tele-democracy – Scientific “collaboratories”

Types of Collaborative Interfaces: Time/Space Groupware Matrix - 1/2

• Schema for representing types of interaction

Same Time Different Times

Same PlaceFace to face

conversation (classrooms, meeting rooms)

Asynchronous interaction

(project scheduling, coord. tools)

Different PlacesSynchronous distributed (shared editors, video

windows)

Asynchronous distributed

(email, listservs, conferences)

Different

Same

DifferentSame

Pla

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Time

Types of Collaborative Interfaces: Time/Space Groupware Matrix – 2/2

Conversation and Collaboration

• Much of the challenge of computer mediated collaboration follows from the lack of elements of human face to face conversation / interaction

• Conversation with others– In each of four ways

• Awareness of others

• How to support people to be able to:– talk and socialise– work together– play and learn together

Different

Same

DifferentSame

Pla

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Time

About Conversation with Others • Various mechanisms and ‘rules’ followed in conversation (Dix)

1. Mutual greetings2. Turn taking to coordinate conversation3. Back channel signals to continue and following4. Farewell rituals5. Implicit and explicit cues

• Mutual greetings:A: Hi thereB: Hi!C: HiA: All right?C: Good, How’s it going?A: Fine, how are you?C: OKB: So-so. How’s life treating you?

Conversational Rules• Typically harder and less “rich” when electronically mediated

– And especially when asynchronous

• Turn-taking to coordinate conversation … + iteration is efficient– A: Shall we meet at 8?– B: Um, can we meet a bit later?– A: Shall we meet at 8?– B: Wow, look at him?– A: Yes what a funny hairdo!– B: Um, can we meet a bit later?

• Back channeling to signal to continue and following– Uh-uh, umm, ahh

• Farewell rituals– Bye then, see you, bye, see you later….

• Implicit and explicit cues– e.g. looking at watch, fidgeting with coat and bags – explicitly saying “Oh dear, must go, look at the time, I’m late…”

Breakdowns in Conversation• Breakdown in communication also harder to handle when electronically

mediated and asynchronous

• As all, easily enough to handle face to face– More challenging, otherwise

• E.g., when someone says something that is misunderstood:

– Speaker will repeat with emphasis:A: “this one?”B: “no, I meant that one!”

– Also use tokens:Eh? Er? Huh? What?

What happens in technology-mediated conversations?

• Do same conversational rules apply?

• Are there more breakdowns?

• How do people repair them?– Phone?– Email?– Instant messaging– Texting?

Design implications

• How to support conversations when people are ‘at a distance’ from each other

• Many applications have been developed– Email, videoconferencing, videophones, computer conferencing,

instant messaging, chatrooms, collaborative virtual environments, media spaces

• How effective are they?

• Do they mimic or extend existing ways of conversing?

Will video be a success using (“next” – now this generation) mobile phones?

• Will the jidder, sudden jerks and shadowsdisappear?

• Will it be possible to establish eye contactand read lips on such a small image?

• Will people find it socially acceptable totalk to an image of someone in the palm oftheir hands?

FYI - … have seen basic ideas

Synchronous Computer-mediated Communication

• Conversations supported in real-time through voice and/or typing

• Examples include video conferencing and chatrooms

• Benefits– Can keep more informed of what is going on – Video conferencing allows everyone to see

each other providing some support for non-verbal communication

– Chatrooms can provide a forum for shy people to talk more

• Problems:– Video lacks bandwidth so jidders and lots of

shadows– Difficult to establish eye contact with images

of others– People can behave badly when behind the

mask of an avatar

Same Time Different Times

Same Place Face to faceAsynchronous

interaction

Different Places

Synchronous distributed

Asynchronous distributed

Asynchronous Communication

• Communication takes place remotely at different times

• Email, newsgroups, computer conferencing

• Benefits include:– Read any place any time– Flexible as to how to deal with it– Powerful, can send to many people– Can make saying things easier

• Problems include:– Spamming– Message overload– False expectations as to when people

will reply

Same Time Different Times

Same Place Face to faceAsynchronous

interaction

Different Places

Synchronous distributed

Asynchronous distributed

Asynchronous distributed interfaces: Different place, different time

• Electronic mail:– can be too loosely

structured – sometimes

overwhelming – transient – tools

• filtering • archiving • mailing lists • discussion groups

– typically text-only, but increasingly includes other structured objects

• graphics • sounds • animations • web pointers • video

Different

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Asynchronous distributed interfaces: Different place, different time (cont.)

• Electronic mail (cont.):– Online directories– Web services with E-mail

• E.g. Hotmail, and Yahoo! Mail– Email on mobile devices

Different

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DifferentSame

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Asynchronous distributed interfaces: Different place, different time (cont.)

• Blogs, wikis, newsgroups, listservers, discussion boards, conferences,

– focused electronic discussions by group of people – online conference

• in addition to listserv tools, may also include additional facilities

– voting – online directories of users – online directories of documents

– online magazines and newsletters – Web-logs/blogs and wikis

Different

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Asynchronous distributed interfaces: Different place, different time (cont.)

• Online and networked communities

– Group identity– Patient support groups– Impact on offline communities– Community policies & freedom of speech– Network communities can be controversial

• hackers • hate groups • para-military groups

– Distance education courses– Reputation managers for online stores

Different

Same

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Synchronous distributed interfaces:Different place, same time

• Synchronous distributed applications – group editing – shared screens for customer assistance – give demonstrations simultaneously at

multiple sites – allow sharing of information for various

applications – interactive games

• Chat, instant messaging, and texting– CHAT, Internet Relay Chat (IRC)– Flamers– MUDS– Texting and cell phones

Different

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Example: Babble

• “Circle with marbles”– Represents people

taking part inconversation ina chatroom

– IBM, Erickson et al, 1999

• Those in middleare doing mostchatting.

• Those towardsoutside less active in conversation

Different

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Synchronous distributed interfaces:Different place, same time (cont.)

• Audio and video conferencing– videoconferencing

• slow response times for entering and leaving session • distracting background audio • difficulty in determining who is speaking • inadequate lighting • difficulty in making eye contact • changed social status • small image size • potential invasion of privacy • need for convenient turn taking • need for document sharing

– issues of ownership and control • private and public workspaces • identity of participants • location of actions • care with updating

• Whether audio or video conferencing is more appealing than chat, IM, and texting, or more effective than asynchronous text, depends on the goals and the task environment

Different

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Face-to-face interfaces:Same place, same time

• Examples– File sharing – Shared workspace – Group activities – Colab and Liveboard– SMART Board– Public spaces facilitate sharing– Sharing photos is very popular– Notification systems

• Innovative approaches to work and learning include: – Shared display from lecturer workstation – Audience response units – Text-submission workstations – Brainstorming, voting, and ranking. – Benefits of electronic meeting systems:

• Parallel communication promotes broader input into the meeting process and reduces the chance that a few people dominate the meeting.

• Anonymity mitigates evaluation apprehension and conformance pressure, so that issues are discussed more candidly.

• The group memory constructed by participants enables them to pause and reflect on information and opinions of others during the meeting and serves as a permanent record of what occurred.

• Process structure helps focus the group on key issues and discourages irrelevant digressions and unproductive behaviors.

• Task support and structure provides information and approaches to analyze it.

Different

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Face-to-face interfaces:Same place, same time (cont.)

• Electronic classrooms

– Active individual learning experiences include using software during class time to:

– Write essays in English or poems in a foreign language – Find antecedents of Impressionism in an art history

library of 9000 images – Run business simulations to increase product quality – Perform psychological statistical analyses – Do landscaping with computer-assisted design and

graphics packages – Compose computer programs and search the Internet

• Small teams and large teams

• Changes teaching style

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Example: Collaborative Virtual EnvironmentsLike Second Life, etc.

• The rooftop garden in BowieWorld, – Collaborative Virtual environment (CVE), supported by Worlds.com– Users take part by “dressing up” as an avatar.

• 100s of avatars to choose from, including penguins and real persons. • Once an avatar has entered a world they can explore it and chat to other avatars.

• Source: www.worlds.com/bowie

• Second Life, etc.

Example: VideoWindow system

• Bellcore - A shared space that allowed people 50 miles apart to carry on a conversation as if in same room drinking coffee together

• 3 x 8 ft ‘picture-window’ between two sites with video and audio

• People did interact via the window but strange things happened

• Talked constantly about the system

• Spoke more to other people in the same room rather than in other room

• When tried to get closer to someone in other place had opposite effect - went out of range of camera and microphone

– No way of monitoring this

Example: Hypermirror

• Allows people to feel as if they are in the same virtual place even though in physically different spaces– Morikawa and Maesako, 1998

(woman in white sweater is in a different room to the other three)

People in different places are superimposed

on the same screento make them appear as if

in same space

Example: Creating personal space in Hypermirror

2) Two in this room are invadingthe ‘virtual’ personal spaceof the other person by appearing to bephysically on top of them

3) Two in the room move apart to allow person in other space more ‘virtual’ personal space

Awareness of others

• Involves knowing who is around, what is happening, and who is talking with whom

• Peripheral awareness– Keeping an eye on things happening in the periphery of vision– Overhearing and overseeing - allows tracking of what others are doing

without explicit cues

• Provide awareness of others who are in different locations

• Media spaces - “extend the world of desks, chairs, walls and ceilings” (Harrison et al, 1997) – Examples: Clearboard, Portholes and Cruiser

Example: Clearboard

• ClearBoard– Transparent board that shows other person’s facial expression on your board as

you draw– Ishii et al, 1993

Example: Portholes (Xerox PARC)

• Regularly updated digitized images of people in their offices appeared on everyone’s desktop machines throughout day and night• Creepy

Notification systems

• Users notify others as opposed to being constantly monitored (cf. Portholes)

• Provide information about shared objects and progress of collaborative tasks

• Example– Tickertape is a scrolling one-line window, going from left to right– Group name, sender’s name and text message– Segall and Arnold, 1997

Key points

• Social mechanisms, like turn-taking, conventions, etc., enable us to collaborate and coordinate our activities

• Keeping aware of what others are doing and letting others know what you are doing are important aspects of collaborative working and socialising

• Many collaborative technologies (groupware or CSCW) systems have been built to support collaboration, especially communication and awareness

Quality of Service

Quality of Service

• A network term …

• Focus here is on how delays, etc. affect user perception, etc.

Quality of Service

• Introduction– Early (and other contexts) computation time– Now, more, “system response time”

• e.g., with web, network congestion, etc., affects response time

– Time is precious (and money)

• Lengthy or unexpected system response time can produce: – Frustration – Annoyance – Eventual anger

• But, (too) speedy and quickly done work can result in users: – learning less – reading with lower comprehension – making more ill-considered decisions – committing more data-entry errors

Models of Response Time Impacts About

• Response time– The number of seconds it takes from the moment users initiate an activity until

the computer presents results on the display

• User think time – The number of seconds the user thinks before entering the next action

• In fact, a number of things going on, e.g., planning– So modeling has challenges

Models of Response Time Impacts

• Design of response times and display rates in HCI must consider: – complex interaction of technical feasibility – cost – task complexity – user expectations – speed of task performance – error rates – error handling procedures

• Overall majority of users prefer rapid interactions – Lengthy response times (15 seconds) are detrimental to productivity – Rapid response times (1 second or less) are preferable, but can

increase errors for complex tasks

Models of Response Time Impacts

• Display Rate – Alphanumeric displays:

• Speed in characters per second at which characters appear for the user to read

– World Wide Web Applications: • Display rate may be limited by network transmission speed or server performance

• Reading textual information from screen is challenging cognitive and perceptual task – Users relax when the screen fills instantly – Beyond a speed where someone may feel compelled to keep up

• Cognitive human performance would be useful for: – making predictions – designing systems – formulating management policies

Models of Response Time ImpactsReview …, but here in text

Limitations of short-term and working memory (Shneiderman):

• Any cognitive model must emerge from understanding of human problem-solving abilities

• Magic number seven - plus or minus two – The average person can rapidly recognize seven chunks of information at a time – This information can be held for 15 to 30 seconds in short-term memory – Size of the chunks depends on the person' s familiarity with the material

• Short-term memory and working memory are used in conjunction for processing information and problem solving

– Short-term memory processes perceptual input – Working memory generates and implements solutions

• People learn to cope with complex problems by developing higher-level concepts using several lower-level concepts brought together into a single chunk

• Short term and working memory are highly volatile – Disruptions cause loss of memory – Delays require that memory be refreshed

Models of Response Time Impacts

Source of errors:– Solutions to problems must be recorded to memory or implemented

• Chance of error increases when solutions are recorded – When using an interactive computer system users may formulate plans and have

to wait for execution time of each step – Long (1976) found unskilled and skilled typists worked more slowly and made

more errors with longer response times • For a given user and task, there is a preferred response time

Conditions for optimum problem solving: – Longer response time causes uneasiness in the user because the penalty for

error increases – Shorter response time may cause the user to fail to comprehend the presented

materials – Progress indicators shorten perceived elapsed time and heighten satisfaction:

• graphical indicators • blinking messages • numeric seconds left for completion

Models of Response Time Impacts

Conditions for optimum problem solving (cont.)– Rapid task performance, low error rates, and high satisfaction when:

• Users have adequate knowledge of the objects and actions necessary for the problem-solving task

• The solution plan can be carries out without delays • Distractions are eliminated • User anxiety is low • There is feedback about progress toward solution • Errors can be avoided or handled easily

– Other conjectures in choosing the optimum interaction speed • Novices may exhibit better performance with slower response time • Novices prefer to work at slower speeds • With little penalty for an error, users prefer to work more quickly • When task familiar and easily comprehended, users prefer more rapid action • If users have experienced rapid performance previously, they will expect in

future situations

Response Time Expectations and attitudes

• Related design issues may clarify the question of acceptable response time – E.g. how long before hearing a dial-tone– Two-second limit (Miller, 1968) appropriate for many tasks

• But, users have adapted a working style and expectation based on responses in fraction of second

– E.g., Cars, dragging icons vs. waiting on traffic light, letters

• Dealing with constancy of expectation – “response-time choke”– System slowed down when load light and potential performance high! – maintain expectations– Makes response time more uniform over time and across users, avoiding expectations that

can’t always be met

• Response time for pages across web sites varies– Affects user interest and quality assessment

• 3 primary factors influence user expectationsand attention to response-time:

– Previous experiences – Individual differences - individual's tolerance for delays – Task complexity

• Simple, repetitive, should be fast

User Productivity• Nature of the task has a strong influence on whether changes

in response time alter user productivity

• Repetitive tasks– Shorter response time means users responds more quickly, but decisions may

not be optimal– Goodman and Spence (1981) – reduced response time lead to more productivity– Teal and Rudnecky (1992) – slower response time lead to more accuracy

• Problem solving tasks– Users will adapt their work style to the response time – Users will change their work habits as the response time changes

• Grossberg, Wiesen, and Yntema (1976) – the time to solution was invariant with respect to response time

• Summary– Users pick up pace of system to work more quickly with shorter response time – Higher throughput of work demands more attention must be paid to minimizing

the cost of delay of error recovery

Variability

• People are willing to pay substantial amounts of money to reduce the variability in their life, e.g., insurance

• Goodman and Spence (1981) – Subjects took more advantage of fast response time by making their

subsequent commands immediately and balancing the time lost in waiting for slower responses

• Modest variations in response time (plus or minus 50% of the mean) appear to be tolerable

• It may be useful to slow down unexpected fast responses

Frustrating Experiences

• (Ceaparu et al., 2004) 46% to 53% of users’ time was seen as being wasted

• Recommendations include improving the quality of service and changes by the user

• Poor quality of service is more difficult in emerging markets and developing nations

• User training can help

• Email a common application, but also a common source of frustration

End

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