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User-Centered Design and Development Instructor: Franz J. Kurfess Computer Science Dept. Cal Poly San User-Centered Design and Development Instructor: Franz J. Kurfess Computer Science Dept. Cal Poly San Luis Obispo FJK 2005

Copyright Notice • These slides are a revised version of the originals provided with Copyright Notice • These slides are a revised version of the originals provided with the book “Interaction Design” by Jennifer Preece, Yvonne Rogers, and Helen Sharp, Wiley, 2002. • I added some material, made some minor modifications, and created a custom show to select a subset. – Slides added or modified by me are marked with my initials (FJK), unless I forgot it … FJK 2005

484 -W 09 Quarter • The slides I use in class are in the 484 -W 09 Quarter • The slides I use in class are in the Custom Show “ 484 -W 09”. It is a subset of the whole collection in this file. • Week 9 contains slides from Chapter 15 of the textbook. FJK 2005

Chapter 15 Design and Evaluation in the Real World FJK 2005 Chapter 15 Design and Evaluation in the Real World FJK 2005

Chapter Overview • Case Studies – Nokia Communicator – Philips Communicator for Children – Chapter Overview • Case Studies – Nokia Communicator – Philips Communicator for Children – TRIS interactive voice response system – Extreme Programming for contextsensitive ads FJK 2005

Motivation • practical examples are often a good source of information • communication is Motivation • practical examples are often a good source of information • communication is an interesting domain since it can use different methods and technologies FJK 2005

Objectives • learn from practical projects how design and evaluation are brought together in Objectives • learn from practical projects how design and evaluation are brought together in the development of interactive products • compare different combinations of design and evaluation methods, and how they are used in practice • identify examples of design trade-offs and decisions for real-world products FJK 2005

Design and evaluation in the real world: communicators and advisory systems Design and evaluation in the real world: communicators and advisory systems

The aims • Show design and evaluation are brought together in the development of The aims • Show design and evaluation are brought together in the development of interactive products. • Show different combinations of design and evaluation methods are used in practice. • Describe the various design trade-offs and decisions that have to be made in the real world.

Key issues: From requirements to design • design cycle to use • combination of Key issues: From requirements to design • design cycle to use • combination of methods to use – for designing and evaluating a product • confidentiality – product being developed is confidential – no users available to test it • user participation – how many users should be involved in tests – expectations from users • evaluation findings

Activity: Convergence of Handheld Devices • there is a significant overlap in usage, technology, Activity: Convergence of Handheld Devices • there is a significant overlap in usage, technology, and interaction methods for mobile devices • sketch a usability evaluation for a device that integrates – music player – voice recorder – PDA – cell phone – camera

Activity: Convergence Characteristics • for the different functionalities mentioned, identify – usage • main Activity: Convergence Characteristics • for the different functionalities mentioned, identify – usage • main tasks, scenarios, constraints – interaction methods or paradigms • communication, selection, commands, … – technologies • required for most important activities

Activity: Convergence Evaluation • develop an outline for a usability evaluation of such a Activity: Convergence Evaluation • develop an outline for a usability evaluation of such a convergence device – design and development method – coordination with evaluation – physical aspects – functionality testing – consistency – user testing

Case Studies • designing mobile communicators – two examples for very different audiences: • Case Studies • designing mobile communicators – two examples for very different audiences: • Nokia’s mobile communicator • Philips communicator for children • redesign of an interactive voice response system – IRS Telephone Response Information System (TRIS)

Nokia 9300 Mobile Communicator http: //www. nokia. com Nokia 9300 Mobile Communicator http: //www. nokia. com

Mobile Communicator • design cycle – iterative user-centered approach • methods – ethnographic research Mobile Communicator • design cycle – iterative user-centered approach • methods – ethnographic research scenarios – task models • confidentiality – first product in the market is key – evaluation must be very limited – no real users

Mobile Communicator Constraints • physical aspects – screen size – number of buttons versus Mobile Communicator Constraints • physical aspects – screen size – number of buttons versus functionality • consistency issues – internal consistency • within mobile software – external consistency • with desktop software • user testing – none before release – summative testing and questionnaires after

Nokia 9300 Review • a review of the device by The Register web site Nokia 9300 Review • a review of the device by The Register web site is at http: //www. theregister. com/2005/ 03/04/nokia_9300_review/page 2. h tml – some serious limitations • no T 9 text input when used as a phone • no pen input

Philips Communicator for Children • design cycle – iterative and evolutionary • methods: – Philips Communicator for Children • design cycle – iterative and evolutionary • methods: – low-fidelity prototyping – participatory design – interface metaphors • physical aspects – color, shape, size, robustness – pen input – bags to protect screen [John Halloran, Sussex University]

Communicator for Children • user involvement – children involved throughout – prototypes evaluated constantly Communicator for Children • user involvement – children involved throughout – prototypes evaluated constantly – invaluable insights for the designers • lessons learned – agree on assumptions in requirements – think of follow-on projects early on – users are not designers – act quick and dirty if necessary [Oosterholt et al, CHI 1996] [John Halloran, Sussex University]

Different approaches • Nokia • Philips – confidentiality constraints – users, but not of Different approaches • Nokia • Philips – confidentiality constraints – users, but not of the proposed product – product may go to market with usability problems – users involved from the start – participatory design – prototype lifecycle – can mean too many ideas, and unfeasible ideas [John Halloran, Sussex University]

Activity: Voice Mail Hell • identify problems with automated phone systems – user interface Activity: Voice Mail Hell • identify problems with automated phone systems – user interface constraints • interaction methods available – cognitive aspects • limitations of human users – user population – design issues – implementation issues – testing and validation

Activity: Interactive Voice Response System Design • Select a domain where such a system Activity: Interactive Voice Response System Design • Select a domain where such a system seems appropriate • develop a script for the first two levels • evaluate the script by using the Wizard of Oz technique

Case Study: Interactive Voice Response System • IRS Telephone Response Information System (TRIS) – Case Study: Interactive Voice Response System • IRS Telephone Response Information System (TRIS) – information about tax issues – simple automated transactions – of 50 million calls, only 14% were handled by TRIS

Interactive Voice Response (IVR) Systems • common in government offices and large companies • Interactive Voice Response (IVR) Systems • common in government offices and large companies • difficult to use – mental model is difficult to form • no visual feedback • user must remember the menu structure • menu structure often shaped by implementation aspects, not user needs – too many choices – deep tree – no grouping

Why was TRIS difficult to use? • menu structure – difficult to remember • Why was TRIS difficult to use? • menu structure – difficult to remember • computational elegance vs. usability – common subroutines for social security number and employee identification number • confusing for users who do not have both • user is asked repeatedly which number is used • composite system – different tasks handled by different systems • each with its own interaction style • users were not told this, but when they moved between the systems they experienced sudden, unexplained changes • the same information is requested repeatedly

TRIS Evaluation • combination of techniques – review of the literature • information about TRIS Evaluation • combination of techniques – review of the literature • information about problems with interactive voice response systems – expert reviews – GOMS analysis of the proposed redesign • simulation – redesign was implemented – usability tests confirmed that the redesigned system offered better usability than the original design • faster task completion times • significantly higher user satisfaction

Using Different Evaluation Methods • broad picture of usability problems • potential benefits of Using Different Evaluation Methods • broad picture of usability problems • potential benefits of the redesigned system – GOMS and heuristic evaluation • user testing – to confirm that the redesigned system offered better usability. • user satisfaction questionnaires – users preferred the redesigned system • gain of ~3 points on a 7 -point scale

XP and Context-Sensitive Ads • visual design of a context-sensitive advert for the Web XP and Context-Sensitive Ads • visual design of a context-sensitive advert for the Web • participant observation study – conducted by a company that produces such adverts • e. Xtreme Programming (XP)as an 'agile' development method – 2 -3 weeks between iterations – code-centric, people-oriented approach http: //id-book. com/casestudy_xp. htm

Active. Ad • analyses the content of a webpage and identifies some key terms Active. Ad • analyses the content of a webpage and identifies some key terms • translated into parameters that define the advert to be shown • Active. Ads are 'clickable' – can link through to any webpage specified by the client • information in the feed is updated periodically – advert will change accordingly • default graphic ('panic’) will be displayed if Active. Ad is not available

XP and User-Centered Design • short, tight iterations of building and releasing software • XP and User-Centered Design • short, tight iterations of building and releasing software • requirements are gathered in terms of 'stories’ – produced by the customer or client – developers estimate how long they think it will take to satisfy them • customer is on site – part of the development team

Betabet Case Study • (re-)design of an Active. Ad for one of Connextra's existing Betabet Case Study • (re-)design of an Active. Ad for one of Connextra's existing clients, Betabet – advert displays the betting odds for the outcomes of sporting events • soccer games, horse racing, … – specific events to be displayed are determined by the contents of the rest of the user's webpage – the advert is designed to sit on a host website and link directly to Betabet's site

Betabet Story • client statement Betabet Story • client statement "We want an improved design for Betabet” • clarification – show the winnings for a £ 10 bet • based on the odds displayed – size to be increased to 120 x 120 (pixels) – more of the advert should be clickable

Storyboards • develop some sketches – capture detailed decisions • size of the columns Storyboards • develop some sketches – capture detailed decisions • size of the columns and rows – broader issues • what the banner across the top should contain http: //id-book. com/casestudy_xp. htm

Photo. Shop Mockup – with notes to explain important aspects Photo. Shop Mockup – with notes to explain important aspects

Static Background • identical for all instances of the ad Static Background • identical for all instances of the ad

Dynamic Ad • ad is populated by specific events • provides information about bets Dynamic Ad • ad is populated by specific events • provides information about bets

‘Panic’ Display • default image to be shown when the ad server is not ‘Panic’ Display • default image to be shown when the ad server is not available

Testing • against a real Web page – dummy version of a client page Testing • against a real Web page – dummy version of a client page • different platforms – desktop, laptop, hand-held, mobile – operating systems: Win, Mac, Linux – browsers: IE, Firefox, Opera, Safari … • in context – test server with live data feed, but not publicly available – live roll-out

Design Issues • ‘panic’ fallback option • page layout – size, alignment, fonts • Design Issues • ‘panic’ fallback option • page layout – size, alignment, fonts • content fit – values must fit into the space available • • clickable elements platform constraints frequent client feedback ongoing effectiveness evaluation – statistics on click-throughs to the client site

Key Points • design involves trade-offs • upgrading a product – design space for Key Points • design involves trade-offs • upgrading a product – design space for making changes is limited • rapid prototyping and evaluation cycles – allow designers to examine alternatives • simulations for evaluating systems used by large numbers of people • piecing together evidence from a variety of sources can be valuable