Explicit design knowledge : investigating design space analysis in practice and opportunities for its development.
In the context of knowledge management, the challenge for organizations is
to convert individual human knowledge into structural capital so that the
knowledge becomes persistent in the organization, making it more accessible
and hence more usable. How to codify the knowledge of a workforce,
including the tacit knowledge of experts, and how to apply that codified
knowledge with success are unresolved issues.
The conversion of individual knowledge into structural capital is of particular
relevance in the field of design. Design is a complex activity that creates
valuable knowledge. However, that knowledge is often implicit, unstructured,
and embedded in procedures, methods, documentation, design artifacts, and
of course in the minds of designers and other project stakeholders. In
addition, design teams are often multidisciplinary and include experts who
apply tacit knowledge to arrive at solutions. Design projects extend over time
so that the risk of losing design knowledge increases.
Information in itself is not knowledge for the purposes of structural capital. A
user interface (UI) design specification for example, does not capture the
knowledge used to create that design. The specification tells us what the
artifact should be, but it does not tell us how the design came to be or why it
is the way it is. Design rationale (DR) is a field of study surrounding the
reasoning behind design decisions and the reasoning process that leads to
the design of an artifact. The objective of creating a design rationale is to
make the reasons for design decisions explicit. Design space analysis (DSA)
is one perspective on design rationale that explores alternative design
solutions and the assessment of each against design objectives. The
rationale behind design decisions provides insight about the design
knowledge that was applied and is therefore, of interest to the structural
capital of organizations. Moreover, the process of making the rationale explicit
is of interest to the domain of user interface design.
The challenge for UI designers and the question addressed in this research is
how to make the design rationale explicit and use it to effectively support the
design process? The proposed solution is to conduct design space analysiS
as part of the process of de.slgn. To. test this solution it is important to explore
the implications of generating design rationale in practice and to explore
whether DSA reflects the knowledge that expert deSigners apply.
The "DSA study" demonstrated and examined the use of design space
analysis by UI experts in a long-term, practical, design setting. The findings
suggest that design space analysis supports communication and the
reasoning process, and it provides context around past design decisions. It
was also found that conducting design space analysis encourages designers
to accumulate design ideas and develop an understanding of design
problems in a systematic way. In addition, the study showed that designers
are capable of producing and using the notation, but that the effort to
conduct DSA is an obstacle to its use in practice. Conclusions are drawn that
DSA can structure the reasoning aspect of design knowledge.
The "design skills study" identified the skills that user interface experts apply in
practice. The findings indicate that many of the skills of UI experts correspond
to the skills that are emphasized by DSA. The study emphasized the
pervasiveness and importance of the communication activity in design, as well
as the role of reasoning in communication and decision making. The study
also identified design activities that receive comparatively little attention from
UI experts and design skills that may be comparatively poor. Conclusions are
drawn that DSA reflects in part the knowledge that designers apply in
Findings from the above studies point to two approaches that maximize the
positive effects of DSA and minimize the effort to conduct a design space
analysis. I describe these approaches as coaching and heuristics. Informal
evaluations indicate that coaching and heuristics warrant further investigation.
The findings from each of the studies have implications for design space
analysis. These are discussed around several themes: the tension between
the processes of designing and structuring design knowledge, the trade-off in
effort between structuring design knowledge and interpreting unstructured
design knowledge, design knowledge and the complementary roles of
communication and documentation, and DSA as it pertains to expert and
It is inevitable that where there are new findings and solutions there are also
new questions to be explored. Several interesting questions raised by these
investigations suggest an agenda for future work.