HCI

Choosing an Evaluation Strategy

User StudiesAnalytical Evaluation

In an iterative UCD processDesigners move rapidly between requirements, conceptual design, physical design, evaluation, prototyping and envisionmentEvaluation is central to the process.Distinguishing conceptual and physical design is very important to ensure a good allocation of function between people and technologiesPrototyping and envisioning ideas is crucial to understanding requirements and design ideas

Envisionment is concerned with finding appropriate media in which to render design ideas. Designs need to be visualizedto help designers clarify their own ideas to enable people to evaluate them. The medium needs to be appropriate for the stage of the process, the audience, the resources available and the questions that the prototype is helping to answer.Forms of EnvisionmentSketches and SnapshotsStoryboardsMood boardsNavigation mapsMind mapsScenariosPrototyping

DocumentationObservationInterviewsFocus GroupsQuestionnairesSimilar ProductsCultural ProbesCreative Alternatives

FunctionalNon-FunctionalDataType , Volatility, size/amount, persistence, accuracyEnvironmentPhysical Social – collaboration and coordination, Organizational – user support, training, validation, resources, managementUserabilities and skills, frequency of use, novice, casual or expertUsabilitylearnability, efficiency, effectiveness, safety, memorability

ISO 9241 StandardsThe effectiveness, efficiency and satisfaction with which specified users achieve specified goals in particular environments. effectiveness: the accuracy and completeness with which specified users can achieve specified goals in particular environmentsefficiency: the resources expended in relation to the accuracy and completeness of goals achievedsatisfaction: the comfort and acceptability of the work system to its users and other people affected by its useAcceptabilityPolitical – is the design politically acceptable? Do people trust it? Do people see it as enhancing their abilities or are they threatened by it?Convenience – Level of awkwardness, change in behaviourCultural and Social habits – Disturb people, human contact – reassurance.Usefulness – In the context of everyday livingEconomic – value for money, change the way people workEngagement (eg. for game interfaces)Identity – a sense of authenticityAdaptivity – personalisation – responsiveness to changing skillsNarrative – telling a good storyImmersion – quality of designFlow – sense of smooth movementUsability is...Helping people access, learn and remember the system …VisibilityConsistencyFamiliarityAffordancesGiving them the sense of being in control, knowing what to do and how to do it …NavigationControl-Dialogue initiative, MappingFeedbackSafely and securely …RecoveryConstraintsIn a way that suits them …FlexibilityStyleConviviality

Guidelines and Principles provide the designer with a framework to provide support for the user in achieving the above points