Software Usability By: Robert J. RemingtonIntroductionSoftware QualityUsabilitySlide 5Usability Engineering (UE)UPA resourcesUser-Centered DevelopmentUsability Design StandardsRapid PrototypingSoftware Usability EvaluationFuture ChallengesSummaryQuestions?Software UsabilitySoftware UsabilityBy: Robert J. RemingtonBy: Robert J. RemingtonEEL6883 – Software Engineering IIEEL6883 – Software Engineering IIDr. Turgut – University of Central FloridaDr. Turgut – University of Central FloridaPresented By: Adam RadwanPresented By: Adam Radwan19 February 200719 February 2007IntroductionIntroduction•Initial thoughts–Frequently software engineers would like to know if there are any good resources and documentation for designing a good GUI–No magic bullet in design, rather there is a set of rules and suggestions outlined in SWEBOK–IBM Report: 42% of users avoided ordering from the web when presented with a poorly designed user interfaceSoftware QualitySoftware Quality•Six ISO Standard high-level characteristics to describe software quality–Functionality–Reliability–Efficiency–Maintainability–Portability–UsabilityUsabilityUsability•Usability definition: “characteristics relating to the effort needed for use, and on the individual assessment of such use, by a stated or implied set of users”•Discussion: What does this definition actually mean? Do the users have any implied prerequisites for system use?UsabilityUsability•Five characteristics–Understandability–Learnability–Operability–Attractiveness (misspelled in the article)–Compliance to application-related standards, conventions, regulations in law, and protocolsUsability Engineering (UE)Usability Engineering (UE)•Human-Computer Interaction (HCI) mismatches have caused fatal mistakes–Casey (Santa Barbara, CA ’93) reports a case where a radiotherapy accelerator proton beam delivered a lethal 25 M eV as a result of a poorly designed, buggy user interface•Usability Professionals Association (UPA) formed at ACM SIG-CHI ’92 by 30 delegates; now over 2000 membersUPA resourcesUPA resources•Body of Knowledge spans studies done at 63 research and development centers•Over 350 articles and laboratory reviews•Human-Computer Interaction journal publishes many up-to-date articles•As a result, UE has expanded its process models, design standards, and evaluation methodology all combines into user-centered development (UCD)User-Centered DevelopmentUser-Centered Development•UCD process (ISO 13407) lists 4 activities undertaken during a project1. Understand and specify the context of use2. Specify the user and organizational requirements3. Produce design solutions4. Evaluate designs against requirementsUsability Design StandardsUsability Design Standards•ISO 9241 lists standards and guidelines for:–Displayed colors–Dialog principles–Presentation of information–User Guidance–Menu Dialogs–Form-filling DialogsRapid PrototypingRapid Prototyping•Creation of a limited, functional user interface for a “test drive” proven effective•Allows for feedback to be obtained in earlier stages of development•Helps avoid errors resulting in design problems from miscommunication about user requirementsSoftware Usability EvaluationSoftware Usability Evaluation•Evaluation should take places at all stages of development•Research centers often use laboratories with one-way mirrors, microphones, and cameras to monitor how a user may interact with a system for the first time•Fitted curve can estimate the number of problems uncovered based on the number of evaluated users•5 users usually uncover approx. 80% of errorsFuture ChallengesFuture Challenges•Web-based user interfaces have been a limiting factor compared to traditional GUI development•Smaller display size and limited input of mobile applications are current drawbacks with many portable implementations•Some systems for I/O and control may best be kept on larger form-factor equipmentSummarySummary•No single proven technique for development of high-usability software•Usability Engineering becoming more advanced, contributions have increased overall software product quality•Further HW/SW advances may solve some known limitations and drawbacksQuestions?Questions?•Any questions?•Time permitting, brief navigation to several websites displaying examples of