William W. Gaver

Ambiguity as a resource for design

Ambiguity is usually considered anathema in Human Computer Interaction. We argue, in contrast, that it is a resource for design that can be used to encourage close personal engagement with systems. We illustrate this with examples from contemporary arts and design practice, and distinguish three broad classes of ambiguity according to where uncertainty is located in the interpretative relationship linking person and artefact. Ambiguity of information finds its source in the artefact itself, ambiguity of context in the sociocultural discourses that are used to interpret it, and ambiguity of relationship in the interpretative and evaluative stance of the individual. For each of these categories, we describe tactics for emphasising ambiguity that may help designers and other practitioners understand and craft its use.

Technology affordances

Ecological approaches to psychology suggest succinct accounts ofeasily-used artifacts. Affordances are properties of the world that are compatible with and relevant for people’s interactions. When affordances are perceptible, they offer a direct link between perception and action; hidden and false affordances lead to mistakes. Complex actions can be understood in terms of groups of affordances that are sequential in time or nested in space, and in terms of the abilities of different media to reveal them. I illustrate this discussion with several examples of interface techniques, and suggest that the concept of affordances can provide a useful tool for user-centered analyses of technologies.

The SonicFinder: an interface that uses auditory icons

The appropriate use of nonspeech sounds has the potential to add a great deal to the functionality of computer interfaces. Sound is a largely unexploited medium of output, even though it plays an integral role in our everyday encounters with the world, a role that is complementary to vision. Sound should be used in computers as it is in the world, where it conveys information about the nature of sound-producing events. Such a strategy leads to auditory icons, which are everyday sounds meant to convey information about computer events by analogy with everyday events. Auditory icons are an intuitively accessible way to use sound to provide multidimensional, organized information to users. These ideas are instantiated in the SonicFinder, which is an auditory interface I developed at Apple Computer, Inc. In this interface, information is conveyed using auditory icons as well as standard graphical feedback. I discuss how events are mapped to auditory icons in the SonicFinder, and illustrate how sound is used by describing a typical interaction with this interface. Two major gains are associated with using sound in this interface: an increase in direct engagement with the model world of the computer and an added flexibility for users in getting information about that world. These advantages seem to be due to the iconic nature of the mappings used between sound and the information it is to convey. I discuss sound effects and source metaphors as methods of extending auditory icons beyond the limitations implied by literal mappings, and I speculate on future directions for such interfaces.

Effective sounds in complex systems: the ARKOLA simulation

We designed an ecology of auditory icons which worked together to convey information about a complex, demanding simulation task, and observed users collaborating on it with and without sound. Our observations suggest that audio cues can provide useful information about processes and problems, and support the perceptual integration of a number of separate processes into one complex one. In addition, they can smooth the transition between division of labour and collaboration by providing a new dimension of reference. These results suggest that auditory icons can play a significant role in future multiprocessing and collaborative systems.

Realizing a video environment: EuroPARC's RAVE system

At EuroPARC, we have been exploring ways to allow physically separated colleagues to work together effectively and naturally. In this paper, we briefly discuss several examples of our work in the context of three themes that have emerged: the need to support the full range of shared work; the desire to ensure privacy without giving up unobtrusive awareness; and the possibility of creating systems which blur the boundaries between people, technologies and the everyday world.

The affordances of media spaces for collaboration

ABSTRACT In this paper, I discuss the affordances offered by media spaces for collaboration, contrasting their properties with those of the everyday medium and exploring the implications for perception and interaction. Collaboration is situated in a physical environment which supports or constrains the various forms social interactions might take. An analysis of the affordances of the environment – the properties that offer actions and interactions to those within it – thus complements analyses which emphasize social and cultural factors. Examining the “physics” of media space systems is helpful both in understanding how people use them to collaborate and in suggesting possibilities for design.

What should we expect from research through design

In this essay, I explore several facets of research through design in order to contribute to discussions about how the approach should develop. The essay has three parts. In the first, I review two influential theories from the Philosophy of Science to help reflect on the nature of design theory, concluding that research through design is likely to produce theories that are provisional, contingent, and aspirational. In the second part, I discuss three possible interpretations for the diversity of approaches to research through design, and suggest that this variation need not be seen as a sign of inadequate standards or a lack of cumulative progress in the field, but may be natural for a generative endeavour. In the final section, I suggest that, rather than aiming to develop increasingly comprehensive theories of design, practice based research might better view theory as annotation of realised design examples, and particularly portfolios of related pieces. Overall, I suggest that the design research community should be wary of impulses towards convergence and standardisation, and instead take pride in its aptitude for exploring and speculating, particularising and diversifying, and - especially - its ability to manifest the results in the form of new, conceptually rich artefacts.

Interaction relabelling and extreme characters: methods for exploring aesthetic interactions

Aesthetics and interaction are interwoven concepts, rather than separate entities. An aesthetics of interaction must consider richness in appearance, actions, and role. Moving beyond a narrow focus on usability in this way requires new methods for understanding design possibilities. Here we describe two: interaction relabelling, in which possible interactions with a known mechanical device are mapped to the functions of an electronic device to be designed; and extreme characters, in which fictional users with exaggerated emotional attitudes are taken as the basis of design to highlight cultural issues. These methods may help designers in considering physical interactions with products on the one hand, and the sociocultural role their products will take on the other.

Synthesizing auditory icons

Auditory icons add valuable functionality to computer interfaces, particularly when they are parameterized to convey dimensional information. They are difficult to create and manipulate, however, because they usually rely on digital sampling techniques. This paper suggests that new synthesis algorithms, controlled along dimensions of events rather than those of the sounds themselves, may solve this problem. Several algorithms, developed from research on auditory event perception, are described in enough detail here to permit their implementation. They produce a variety of impact, bouncing, breaking, scraping, and machine sounds. By controlling them with attributes of relevant computer events, a wide range of parameterized auditory icons may be created.

Sound support for collaboration

Shared work often involves fluid transitions between relatively focussed collaboration, division of labour, general awareness and serendipitous communication. This leads to a tension in the design of software systems meant to support shared work: focussed collaboration implies the need to coordinate peoples views of work objects, while division of labour requires individual control over views. A similar tension exists in the office environment as well: group engagement in the workplace depends on a shared context, but individual work is facilitated by privacy and freedom of action. Auditory cues have the potential to reduce these tensions because graphics and sound can provide two independent ways to present and obtain information. I illustrate the potential of sound in collaborative systems with observations drawn from two systems: the ARKola simulation, which explores the effects of sound on collaboration within a workstation environment; and EAR, in which auditory cues are used to increase general awareness of events and encourage group engagement within the workplace itself. These examples suggest useful functions sound can play in collaborative systems.