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Non-Market Valuation: Contingent Valuation. REM-621 Environmental and Ecological Economics Guest Lecturer: Jonn Axsen Fall 2011. Why we value the environment. Cost benefit analysis Projects New regulations / policies Assessment of environmental damage (compensation / liability)
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Non-Market Valuation:Contingent Valuation REM-621Environmental and Ecological Economics Guest Lecturer: Jonn Axsen Fall 2011
Why we value the environment • Cost benefit analysis • Projects • New regulations / policies • Assessment of environmental damage (compensation / liability) • Green accounting (green GDP)
Framework for valuation • Values include: • direct use values • Recreation, harvesting • indirect use values • Ecosystem services like soil retention, climate stabilization, water management, life support • Use (both indirect and direct) values can be for present or future use (option value / bequest value) • non-use values • Existence value • Total economic value = direct use + indirect use + non-use
Techniques for valuation In addition to these methods, benefit transfer is used to apply results of one study – in one region – to another region.
Revealed and Stated Preferences • Revealed: Observed in market (real) • Stated: Elicited from consumer (hypothetical)
Initial thoughts on survey?How did you feel?What was the survey trying to do?
State Preference Approaches • Contingent valuation • Open-ended • Close-ended: iterative bids, dichotomous choice • Choice experiments (bundles of attributes) • Contingent ranking
Contingent Valuation “asks people what they would be willing to pay (or accept in compensation) for changes in quality of an environmental amenity”
Evolution of contingent valuation techniques - example • “What is the most you would be willing to pay to ensure that the old-growth forest in the Stein Valley was preserved in a park?” • “Suppose the only way of preserving the old-growth forest in the Stein Valley is if British Columbia residents agree to pay additional taxes to establish a park in this region. What is the maximum you would be willing to pay, in additional taxes per year, to make sure that this park is created?” • Adds context • “Government is considering establishing a park to protect old-growth forests in British Columbia’s Stein Valley. Creation of the park will increase your taxes by $10/year. Would you be in favour of this measure?” • Dichotomous choice is more natural • Adds realism (respondents are more familiar with taxation than with valuation) • Reduces strategic overstatement
WTP (I would pay…) vs. WTA (I would have to be paid…) • Your Example: Open-ended valuation of Spotted Owls Which is more appropriate: WTP or WTA?
Discrete Choice • Characteristic theory of value: • Value is based on attributes • Choice sets: Compare bundles of attributes • What did we use in Gondola survey? • Respondent chooses preferred bundle • Statistically estimate a flexible model, calculating • Sample utility function, weighting each attribute • MWTP for change in attribute • Value of a combination of attributes • % of sample (or market share) choosing particular bundle • Contingent ranking is similar, but multiple bundles are ranked
Discrete Choice • Your Example: Choices between SFU Gondola and Bus Same as34% GHG Reduction
Simulating Policy Effects • Status quo: same price, trip time, owls, GHGs • Gondola = 67% • Alternative Gondola Policies: • Disturb one pair of owls • Gondola = 37% • Cut GHGs by 50% • Gondola = 93% • Disturb two pairs of owls, cut GHGs by 50% • Gondola = 51% • Disturb one pairs of owls, cut trip time by 10 min. • Gondola = 57% • Disturb one pair of owls, cut price by $7 • Gondola = 49%
SP Limitations: Bias • Hypothetical bias • Difficult to envision? • Budget constraint? • WTP estimates are too large • Social desirability bias: appear “good” • Interviewer bias: influence from interviewer • Anchoring: influenced by starting point • Framing bias: influenced by context
Other SP Limitations • WTA vs. WTP • Appropriate measure depends on situation • In practice, WTP is usually used • Strategic response • Respondents may try to influence public decisions • Over-value if they won’t have to actually pay • Under-value if they might have to actually pay • What about “protest” responses? • Lack of knowledge • Do people understand value provided by that service • Uncertainty, instability in preferences?
Getting the most out of SP Methods • Sampling technique • Choose appropriate population • Select representative sample (or weight correctly) • Maximize response rate (or minimize non-response bias) • Survey mode • Face-to-face interviews are ideal • Carefully choose among phone, mail or internet • Conservative survey design • Use WTP rather than WTAP (NOAA cuts WTP by 50%...) • Remind respondents of substitute resources • Referendum/choice rather than open-ended • Incorporate/measure respondent uncertainty?