Abstract:
While contingent valuation (CV) and choice experiments (CE) share many common features,
from a theoretical standpoint the essential and defining difference between them is that while CV
exercises pose a single valuation task, CE studies comprise multiple choices. This repetition of
valuation tasks brings two unique features to the CE exercise: first an awareness of multiple
valuation tasks may of itself influence stated preferences (for example via the adoption of
strategic behaviour or specific multiple task response heuristics); second, the repetition of choice
tasks delivers learning opportunities to the respondent (by providing opportunities to learn about
one's own preferences for a new good, or to learn about the response mechanism itself). We
conduct a controlled design CE exercise permitting investigation of both the awareness and
learning issues. Specifically the awareness issue is investigated by varying the visible choice set
(VCS) of valuation tasks of which a subject is aware of at any given point in a valuation exercise.
The issue of learning through repetition is handled by a unique CE design which repeats
specified valuation tasks at different points in the CE exercise. We find that both the awareness
and learning issues impact significantly upon stated preferences. These findings shed light upon
the cognitive processes dictating responses in CE exercises and permit a more informed
comparison with CV results.
