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Designing the Digital Knowledge Gatewayo Summer Course L385To School of Information
o Instructors:o Andrew Dillono Dan Updegroveo Liz Aebersold + guests
What is the Knowledge Gateway?
o A means of providing ‘all Texans with access to the University's wealth of knowledge and cultural assets’.
o "The great treasures of this institution belong to all citizens of the state. We want all to use them….Also, we intend to be a leader in the new realm where research, learning and scholarly discourse are not limited by the walls of classrooms and laboratories." o President Faulkner, 2002.
User experience
o The human requirements for and responses to the interactions enabled by an interactive device
o Considered at four levels:o Physical o Perceptual o Cognitive/Affective o Social
User-centered design:
o Early & Continual focus on userso observation, interview, participation
o Early & Continual focus on user testingo test everything all the time
o Iterative designo Design and redesign on basis of users
o Integrated designo all work geared to one goal - a high
quality user experience
7 basic properties of all users: a personal list
o Goal oriented, but its their goals!o Learn by doing, avoiding instructionso Make mistakes and require immediate feedbacko Drawn by utility then usabilityo Influenced by aesthetics and by contexto Change with experience but remain uniqueo Limited attention and seek to minimize effort
PerceptionDecision &ResponseSelection
ResponseExecution
Attention Resources
Long-termMemory
Working Memory
Memory
stimulus
Implications for design:
o Designer never sees exactly what the user sees
o Experience and repeated use shift the interpretations of users
o Differences among users can lead to radically different perceptions of the information space
User differences: Aging
o Increasing proportion of the population
o Cognitive speed diminisheso LTM retrieval significantly slowed
o Perceptual capability is diminishedo Decision making quality is better
o lifetime of experience to call upono Vast redundancy of CNS helps us!
User differences: ability
o Typical human performance differences are 2:1
o Within HCI there are examples of differences of 20:1
o Implication is that a technology supposed to enable humans is failing large numbers of users
User differences: experienceo Best predictors of user acceptance of a
new systemo Utility
o Does user see the value o Experience
o Those who have used, will use
o Implication: if you do not know the technology, you may never see its value
Project ideas
o How to convey the potential of the KG to inexperienced users?
o How to design so as to support users of varying levels of ability?
o How do the demographics of the state suggest we should implement key features for reading on screen?
How is UE measured?
o Multiple methodso Process v. Outcomeo Behavior and thoughtso In person or remote
Outcome
Process
Thought Behavior
Task completionTime on task# of errorsUse of functions
Self report of utilitySatisfaction dataEstimate of performance
Think-aloud protocolWalkthroughs
Transaction data e.g., navigation pathsError recovery
In the KG context
o Range of tasks:o Logging in/setting upo Query formulationo Browsingo Studying materials
How do we best capture data to analyze the user experience for these?
Project ideas
o How can we gain reliable data from users?o Does log data match observation?o Does initial impression last?o Do surveys and suggestions from
users have real value?o Can we explain the KG with simple
examples and screenshots?
And where to start?
o At this stage of the process, reliable user data is in short supply
o Establishing requirements is messyo Compare other gatewayso Prototype and testo Scenario generation
Scenarios
o A scenario is a story about an interaction a user experiences with an information resource which conveys explicit information about what a user does in a specific context, how s/he experiences the interaction, what the goals are and what actions are taken.
o Scenarios have plots, sequences, events etc.
Elements of scenarios
o Settings o (office, car, library etc.)
o Actors o (accountant, patron, trainee etc.)
o Task goals o (compare budget data, locate a file)
o Plans o (locating file will answer question about X)
o Evaluation o (Search engine output is not helping)
o Actions o (inputting data)
o Events o (feedback from other person, from interface)
Why use scenarios?
o Help manage trade-offs in design by articulating what happens without saying how it happens
o Are flexible and safe for exploring optionso Keep design space open and avoid premature
commitmento Can be presented in a form that everyone
understandso They are vivid, and encourage ‘what-if?’
discussions
o See Rosson and Carroll (2001) in suggested readings
KG example
o Setting: At home, dial up connection, aloneo Actor: Female, retired bank tellero Goal: Locate pointers to info on brain tumorso Plan: Try searching on key wordso Action: Inputs terms in top level search
functiono Outcome: List of 100 ‘relevant’ hitso Evaluation: Output is vague and overwhelming!
More positive example
o Setting: In a café, using wireless PDAo Actor: Environmental inspectoro Task goal: Locate estimates of local pollutiono Plan: Open up bookmarked page of UT siteo Action: Browsing and scrolling data displayo Outcome: Data table displayed on small screeno Evaluation: Who needs anything but KG?
Key issues:
o Articulate a flow or sequence
o Cover context, user, task, mental and physical activities, outcomes and evaluation
o Describe the details
o There is no right or wrong scenario
Project ideas
o Develop and evaluate 3 reliable scenarios of use for the KGo Work with design teamo Identify user groupso Mock up screenso Gain user input
o Outcome: clear articulations of what is needed for given contexts
Ideas based on what is out there:o How long is a typical interaction?
o How many tasks does that entail?o Why do users not use and why?
o What does it take for a new user to engage with audio or video?
o Are uses online different? How?o How do we get reliable suggestions for
design?o What do other ‘gateways’ know?
o How did they learn it?
Determinants of usability rating
Effectiveness
Efficiency
Satisfaction
UsabilityRating
Usability is not fixed
o Usability is a ‘negotiable’ constructo Should be expressed in measurable termso Measures should reflect design questionso Capture performance and affect
o effectivenesso efficiencyo satisfaction
o Compare across contexts with caution!
Specific measures to consider
Usabilitycriterion
Measure Data
Effectiveness Task completion % of completion,x-pt scale
Efficiency Time on task # of seconds time on sub-tasks
Navigation path # of stepsdeviation fromideal# of backtracks
Cognitive effort Think aloudprotocolTLX scoresUser judgement
Satisfaction Ratings ofapplication
Scores on scalesInterviewresponsesPreferences
Perceptions ofeffectiveness,efficiency etc.
As above
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