¥Strategic
bias arises when the respondent provides a biased answer in order to influence
a particular
outcome.
If a decision to preserve a stretch of river for fishing, for example, depends on
whether or not the survey produces a sufficiently large value for fishing, the respondents
who enjoy fishing may be tempted to provide an answer that ensures a high value, rather
than a lower value that reflects
their true valuation.
¥ Information bias may arise whenever
respondents are forced to value attributes with which they
have little or no experience. In
such cases, the amount and type of information presented to
respondents may affect their answer Non-response bias is a concern when sampling
respondents, since individuals who do not respond are likely to have, on
average, different
values than individuals who do respond.
¥ Estimates of nonuse values are difficult
to validate externally.
¥ When conducted to the exacting standards
of the profession, contingent valuation methods can
be very expensive and time-consuming, because of the extensive pre-testing and survey
work.
¥Many people,
including jurists policy-makers, economists, and others, do not believe the results of
CV.