At this point, we decided to focus almost entirely on structural engineers, with a few
interviews in neighbouring disciplines. ‘Structurals’ were chosen because they are (1)
core members of building design teams, (2) relatively sophisticated and frequent users of
mathematics, compared with the related disciplines.
Data was collected as follows.
Interviews: We developed an interview schedule, which went through three iterations as
our focus on issues became more refined. In the early part of the project we asked
structural engineers in interviews to talk generally about the roles of calculation and
‘intuition’ in their design work, and what they considered to be the ‘mathematical
elements’ of engineering design. On the basis of the common elements of their responses
we were able to focus our questions (at the same time tuning into the language of the
engineers) onto some key structural ideas (see Section 4 for a description of these), and
asking how do mathematical ideas become ‘embedded’ within those ideas. Finally, in the
last part of the project, when we broadened the range of interviewees from structural
engineers to related engineering specialisms, we re-phrased our interview questions into
more general terms, looking for analogous key ideas to those we had found from
structural engineers.
In all the interviews, we requested the engineers to bring drawings and documents from
one or two particular projects, and on some occasions we were able to receive
demonstrations of the use of software packages. Part of each interview was focussed on
these specific artefacts, and we asked the interviewees to describe ‘critical incidents’
relating to the documents and/or software.
Each interview was audio-taped and transcribed. Periodically, memos were written which
identified questions and issues for further study: transcripts were reviewed independently
by the researcher and project director and separate memos written that were subsequently
synthesised.
Project meetings: We observed meetings over an initial 4-week period. These were audio-
taped (given the dominantly verbal nature of the discourse, videotape was not used), and
relevant portions transcribed. These meetings were, as we had been informed, mostly
about project management, but they did provide a source of contacts and relevant issues
that could be followed up subsequently in interviews.
Project documents and computer files: The interview and meeting data was enriched by
working documents, computer outputs, and computer files from the projects under
discussion.
Email trails: On a number of occasions we were able to follow interactions between
specialist domains in the firm by tracing email conversations. We followed up these email
trails by directly communicating with one or more participants by telephone or face-to-
face interviews.
As the body of data and analytical memos grew, we were able to choose our data sources,
including the choice of individuals to interview, according to the principles of theoretical
sampling, in which we identified gaps in our data or particular issues for follow-up, and
collected further data from sources chosen to inform our emerging theory and clarify
hypotheses and categories. As part of this process, we developed a coding scheme for
data analysis, which was taken as the starting point for the preliminary coding in phase 4.