The choice task then begins in earnest, with respondents stating their preferred
allocations across the modal alternatives for eight unique choice sets, each of which offer different mixes of costs and levels-of-service. This choice data
represents the central information analysed within discrete choice models to
yield behavioural measures relating to preferences for each mode as functions
of cost/level-of-service trade-offs, and characteristics of corridors, firms and
cargo. The survey instrument concludes with a brief series of attitudinal
questions, and the opportunity for respondents to state their opinions
on shipping and greenhouse gas emissions, and on the potential value of
integrated short sea shipping alternatives.
We now turn to a discussion of the experimental design process, which
specified the particular attribute level mixes across alternatives for each choice
set in the survey instrument.
Experimental design