Scenario Adjustment in Stated Preference Research
Loading...
Date
2009-11-22
Authors
Cameron, Trudy Ann
DeShazo, J. R.
Johnson, Erica H.
Journal Title
Journal ISSN
Volume Title
Publisher
University of Oregon, Dept of Economics
Abstract
Stated preference (SP) survey methods have been used increasingly to assess willingness
to pay for a wide variety of non-market goods and services, including reductions in risks to life
and health. Poorly designed SP studies are subject to a number of well-known biases, but many
of these biases can be minimized when they are anticipated ex ante and accommodated in the
study’s design or during data analysis. We identify another source of potential bias, which we
call “scenario adjustment,” where respondents assume that the substantive alternative(s) in an SP
choice set, in their own particular case, will be different than the survey instrument
describes. We use an existing survey, developed to ascertain willingness to pay for private
health-risk reduction programs, to demonstrate a strategy to control and correct for scenario
adjustment in the estimation of willingness to pay. This strategy involves data from carefully
worded follow-up questions and ex post econometric controls for each respondent’s subjective
departures from the intended choice scenario. Our research has important implications for the
design of future SP surveys.
Description
2, 25, 19 p.
Keywords
Scenario adjustment, Scenario rejection, Stated preference, Value of a statistical life, Value of a statistical illness profile, VSL