Source Interface Hall of Shame Fall 2004 6 831 UI Design and Implementation 1 Fall 2004 6 831 UI Design and Implementation Iterative Design 2 Requirements Design Design Evaluate Implement Code Integration Task Analysis Acceptance Release Fall 2004 6 831 UI Design and Implementation 3 Fall 2004 6 831 UI Design and Implementation 4 1 User interface design is risky Requirements So we re likely to get it wrong Design Users are not involved in validation until acceptance testing Code So we won t find out until the end Integration UI flaws often cause changes in requirements and design Acceptance So we have to throw away carefully written and tested code Release Fall 2004 6 831 UI Design and Implementation 5 Fall 2004 6 831 UI Design and Implementation Evaluate 6 Every iteration corresponds to a release Design Fall 2004 Evaluation complaints feeds back into next version s design Using your paying customers to evaluate your usability Implement 6 831 UI Design and Implementation They won t like it They won t buy version 2 7 Fall 2004 6 831 UI Design and Implementation 8 2 Design Implement Evaluate Fall 2004 6 831 UI Design and Implementation 9 Fall 2004 6 831 UI Design and Implementation 10 Iterative design Early focus on users and tasks Early iterations use cheap prototypes Parallel design is feasible build test multiple prototypes to explore design alternatives user analysis who the users are task analysis what they need to do involving users as evaluators consultants and sometimes designers Later iterations use richer implementations after UI risk has been mitigated More iterations generally means better UI Only mature iterations are seen by the world Constant evaluation Users are involved in every iteration Every prototype is evaluated somehow Fall 2004 6 831 UI Design and Implementation 11 Fall 2004 6 831 UI Design and Implementation 12 3 Design 8 12 4 35 6 7 6 831 UI Design and Implementation 1 Iterative design 200 iterations for user guide Evaluation at every step You are not the user Non English speakers had trouble with alphabetic entry on telephone keypad 13 2 6 831 UI Design and Implementation Scenarios User guides Simulation Wizard of Oz Prototyping tools IBM Voice Toolkit Fall 2004 3 6 831 UI Design and Implementation 14 Identify characteristics of target user population First step of user centered design User analysis who is the user Task analysis what does the user need to do Fall 2004 Cheap prototypes Task analysis Design sketches Paper prototype In class user testing Computer prototype Heuristic evaluation Implementation User testing Implement Evaluate Fall 2004 1 2 3 4 5 6 7 8 0 Age gender ethnicity Education Physical abilities General computer experience Skills typing reading Domain experience Application experience Work environment and other social context Relationships and communication patterns 15 Fall 2004 6 831 UI Design and Implementation 16 4 2 Techniques Many applications have several kinds of users Example Olympic Message System Questionnaires Interviews Observation Athletes Friends family Telephone operators Sysadmins Obstacles Developers and users may be systematically isolated from each other Tech support shields developers from users Marketing shields users from developers Some users are expensive to talk to Doctors executives union members Fall 2004 4 6 831 UI Design and Implementation 5 17 Fall 2004 Identify the individual tasks the program might solve Each task is a goal what not how Often helps to start with overall goal of the system and then decompose it hierarchically into tasks Grocery shoppers Wide range of ages 10 80 and physical abilities height mobility strength No computer experience No training walk up and use Knowledge of food but not about supermarket inventory techniques Supermarket shoppers often ask each other for help finding things Overall goal shoppers pay for their own groceries Tasks Major user classes Enter groceries into register Bag groceries Pay Family shopping is often done by women often accompanied by small children Store clerks who need to help shoppers 6 831 UI Design and Implementation 18 2 Who are the users Fall 2004 6 831 UI Design and Implementation 19 Fall 2004 6 831 UI Design and Implementation 20 5 2 4 What needs to be done Preconditions Preconditions All the groceries you want are in your cart Tasks on which this task depends Information that must be known to the user Subtasks What steps are involved in doing the task Enter prepackaged item Enter loose produce Subtasks Subtasks may be decomposed recursively 6 831 UI Design and Implementation 6 2 2 Enter groceries into register What must be done first to make it possible 0 5 Goal Goal Fall 2004 21 Fall 2004 Where is the task performed 6 831 UI Design and Implementation 22 2 Interviews with users Direct observation of users performing tasks Front of supermarket standing up How often is the task performed At most a few times a week What are its time or resource constraints A minute or two How is the task learned By trying it By watching others By being shown how by store personnel What can go wrong Exceptions errors emergencies Barcode is missing or smudged Shopper wants to buy alcohol or cigarettes Who else is involved in the task Fall 2004 6 831 UI Design and Implementation 23 Fall 2004 6 831 UI Design and Implementation 24 6 2 Duplicating a bad existing procedure in software Failing to capture good aspects of existing procedure 1 2 Questions to ask Why do you do this goal How do you do it subtasks Look for weaknesses in current situation Goal failures wasted time user irritation Contextual inquiry Participatory design Fall 2004 6 831 UI Design and Implementation 4 25 7 Fall 2004 Observe users doing real work in the real work environment Be concrete Establish a master apprentice relationship 6 831 UI Design and Implementation 26 Include representative users directly in the design team OMS design team included an Olympic athlete as a consultant User shows how and talks about it Interviewer watches and asks questions Challenge assumptions and probe surprises Fall 2004 6 831 UI Design and Implementation 27 Fall 2004 6 831 UI Design and Implementation 28 7
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