Breath of Clarity

Contingent Valuation Questions

5. Design some contingent valuation-type questions for evaluating the value to people of improving the air quality in the Grand Canyon. (Field and Field 2017, 165)

I identified my contingent valuation-type questions in bold along with the logic I used to design them:

Do you identify the current air quality at Grand Canyon National Park as unsatisfactory? Is citizen payment necessary in order to improve air quality at Grand Canyon National Park?

In the Jacksonville study, the authors mentioned “trust in authorities” is a factor significantly impacting WTP for clean drinking water (Chatterjee et al. 2017). The authors explained a higher trust in authorities results in participants being satisfied with water quality staying the same and decreases WTP for a cleaner alternative. Insofar as the Grand Canyon study’s participants trust a change is going to happen without interference, there would be a low WTP. For the Grand Canyon study, I would provide information about the existing air quality’s condition and how clean air quality actually impacts a visitor’s experience. Specifying the problem and clearly painting a picture of the superiorly clean vision informs the participant before answering a question about WTP that directly lists various prices.

How much of an increase in your entrance fee would you be willing to pay to improve the air quality at Grand Canyon National Park ($0, $2; $8; $10; $15)?

Similar to the limitation Emily addressed concerning the vague, subjective definition of clean drinking water, the same is true in regard to improved air quality. I would outline a description of potential degrees to which the air quality can be improved and then design a question with specific cost options similar to the Jacksonville study’s question “How much of an increase in your monthly water bill would you be willing to pay to improve the quality of your water ($15; $10; $5; $3; $2; $0)?” (Chatterjee et al. 2017). Moreover, considering the Grand Canyon is a federally controlled park, it is crucial to explain how the visitor money would be allocated to improve air quality. Communicating the tools in place for scientists to throughly understand the area and actually improve air qualityLinks to an external site. supports the participants feeling as though the money would be used efficiently (Karlstrom et al. 2019). Doing so supports the participant having accurate benefit estimation.

Do you have an electric vehicle or use any other sustainable mode of transportation in daily life?

The Jacksonville study’s authors explained a limitation of the contingent valuation is “this methodology emphasizes the stated preferences of respondents and stands in contrast to those approaches that use revealed preferences” (Chatterjee et al. 2017). However, in the Jacksonville study, the questions were designed to understand specific actions already being conducted in households i.e. using water filters, drinking bottled water and cooking. While contingent valuation is reliant on participant responses accurately reflecting truth, the questions are still geared at identifying participant preference in terms of behavior.

Would you pay $2 extra to contribute to improvements in air quality at Grand Canyon National Park?

I also concur with the Jacksonville study’s use of closed-ended questions as the type of inquiry is “incentive-compatible and have become the standard approach to simulate WTP” (Chatterjee et al. 2017). The closed-ended method states a minimum amount and simply asks the participant to answer “yes” or “no” in terms of WTP which mimics an actual market for a private good or the choice facing citizens in a referendum for a public good (Chatterjee et al. 2017). In order to minimize the hypothetical quality of a contingent valuation study, the test needs to be as close to using actual or simulated market transactions as possible.


Karlstrom, Karl, Laura Crossey, Peter Huntoon, George Bilingsley, Michael Timmons, and Ryan Crow. 2019. “One Hundred and Sixty Years of Grand Canyon Geological Mapping” Journal of Arizona History: (655-674). to an external site.

Chatterjee, Chiradip, Russell Triplett, Christopher K. Johnson, and Parvez Ahmed. 2017. “Willingness to Pay for Safe Drinking Water: A Contingent Valuation Study in Jacksonville, FL” Journal of Environmental Management 203 (August): 413-421.

Comment by Rachel Hartley:

Excellent contingent valuation questions! Your second question reminded me of a concept Catherine mentioned in response to Ed’s article for Chapter 6, regarding the importance of using specific numeric expressions of benefits, likelihoods of an outcome, etc. since people tend to have trouble accurately envisioning ambiguous quantifiers such as “probable,” “significant,” or “unlikely.” I think employing a bidding game approach like adding a specific price value to entrance fees in the Grand Canyon Park scenario in relation to specifically outlined air quality measures is a smart pairing and approach to the analysis. For your fourth question, which as you note provides consumers a simple choice that mimics a market good scenario, I wonder if it would be beneficial to present the information about what tools are available for scientists to assess and improve air quality alongside this question as well.