Grantee Research Project Results
2018 Progress Report: Estimation of Spatially Explicit Water Quality Benefits throughout River Systems: Development of Next Generation Stated Preference Methods Using National Probability Samples and Online Labor Pools
EPA Grant Number: R836167Title: Estimation of Spatially Explicit Water Quality Benefits throughout River Systems: Development of Next Generation Stated Preference Methods Using National Probability Samples and Online Labor Pools
Investigators: Johnston, Robert J , Moeltner, Klaus , Wollheim, Wil
Current Investigators: Johnston, Robert J , Wollheim, Wil , Moeltner, Klaus
Institution: Clark University , Virginia Tech , University of New Hampshire
Current Institution: Clark University , University of New Hampshire , Virginia Tech
EPA Project Officer: Packard, Benjamin H
Project Period: April 1, 2016 through March 31, 2019 (Extended to March 31, 2022)
Project Period Covered by this Report: April 1, 2018 through March 31,2019
Project Amount: $799,919
RFA: Water Quality Benefits (2015) RFA Text | Recipients Lists
Research Category: Water
Objective:
This project will develop novel, modular approaches to stated preference valuation designed to address the challenges of use/nonuse value estimation for complex, temporally/spatially explicit aquatic ecosystem change with heterogeneous benefits for different user and nonuser groups. The approach, denoted Free-form Choice Experiments (FCEs), will restructure the way that willingness to pay (WTP) is elicited and estimated in survey-based valuation, hybridizing methods from contingent valuation, choice experiments, revealed preference modeling, online labor pool sampling, and Bayesian econometrics. The approach will be developed to estimate WTP for water quality and ecosystem service improvements throughout river networks. FCEs are designed to be transformative across multiple dimensions, including: (a) novel ways to elicit stated preferences and design surveys, with scenarios coupled directly to ecological models, (b) flexible value elicitation and modeling that generates benefit functions linked to temporally/spatially explicit effects, (c) an ability to evaluate the relevance of many ecological indicators to different user/nonuser groups, (d) novel modeling of data using Bayesian econometrics, and (e) new approaches to stated preference sampling using online labor pools. Biogeochemical forecasts for valuation scenarios will be projected using FrAMES (Framework for Aquatic Modeling of the Earth System), a process-based spatially explicit water quality model. These methods will provide a means to estimate economic values for a variety of surface waters and types of quality change.
Progress Summary:
We have completed Tasks I, II, III and IV as outlined in the project proposal. Tasks V and VII are in progress, and Tasks VI, VIII, IX and X are still to be completed. Conceptual model development, water quality modeling, and FCE scenario design have been completed. Survey development included the use of FrAMES to develop water quality scenarios and indicators, development of choice questions around those scenarios, and completion of additional questionnaire materials and supporting questions. Questionnaires have been pretested and revised with input from focus groups and cognitive interviews, with additional feedback from external experts in stated preference methodology and survey design. This input has been combined to develop final survey templates. We have jointly developed this scenario design with Bayesian econometric models suitable for model estimation, and have evaluated model performance using simulated response data. We are now developing the surrounding Amazon MTurk code and shell that will enable the questionnaire to be pilot tested and implemented on the MTurk platform.
Development of Water Quality Indicators and Scenarios: The Framework for Aquatic Modeling in the Earth System (FrAMES) was applied to the Northeast US region to simulate specific conductivity, fecal coliform, and dissolved inorganic nitrogen, which were used to characterize three water quality indicators of direct relevance to the public. An aquatic life indicator was developed based on a reported range of chloride concentrations that affect aquatic organism survival. A water safety indicator for drinking and recreation was developed based on fecal coliform count guidelines. Finally, an indicator for overall water quality was developed as a combined metric using all three modeled solute concentrations, compared to reference conditions for the case study watersheds. Grounded in these indicators and focus group input, we developed policy scenarios that included combinations of region-wide management actions to generate future scenarios of water quality change for the valuation survey. Forty-one scenarios were defined using a full factorial (36) of region-wide management actions, including: riparian buffer expansion (0%, 90% of agricultural and developed land); waste water treatment plant upgrades (50%, 90% from secondary to tertiary treatment); storm water retention (0%, 65%, 90% urban rain infiltration); and road salt application (700, 4000, 7600 g/mm/m2 snowfall). Five additional scenarios are added representing minimum and maximum levels of storm water retention and road salt application applied only in northern (ME, NH, VT) and southern (CT, MA, RI) New England states, with riparian buffers and WWTP upgrades at maximum levels in the target region only.
Final Development and Testing of Questionnaires: Based on these scenarios, complete versions of questionnaires have been developed, pretested and finalized. Valuation scenarios compare outcomes for these indicators with and without proposed management alternatives. These outcomes, paired with the hypothetical household cost of each management alternative (8 possible bid levels), comprise each valuation scenario (or question). Scenarios are illustrated for a case study area of approximately 95,800 miles of rivers and streams in Connecticut, Massachusetts, Rhode Island, Vermont, New Hampshire and Maine, over 71,992 square miles of land. All maps have GIS zoom capability, enabling respondents to view projected water quality baselines and changes at any desired magnification and local area. Survey design tasks during year three included final development and pretesting of the questionnaire. A total of 7 focus groups with 54 non-expert respondents were held between 2017 and 2019, with more than 20 additional one-on-one cognitive interviews. Focus groups and interviews were held with respondents from six different states. Additional feedback on survey design was solicited from external experts in stated preference design. Grounded in these activities, we have finalized the questionnaire template. Tasks also included initial development of the MTurk interface, including the "Human Intelligence Task" (or HIT) shell through which the embedded questionnaire will be presented to MTurk respondents, and the data from survey responses recorded. These data will be used for model estimation via application of novel Bayesian techniques.
Development of Bayesian Econometric Models: Econometric tasks completed in year three included (i) a simulation exercise to inform the optimal number and placement of bid values to be offered to respondents, (ii) a simulation exercise to determine the diagnostic and predictive abilities of the Bayesian model search algorithm, and (iii) a simulation exercise to test the algorithm under realistic field conditions, i.e. using the same water quality scenarios as will be given to respondents in the actual survey. These simulations were used to inform bid vector development for survey scenarios and evaluate the performance of the Bayesian estimators and search models. We are now in an excellent position to process the field data when they become available.
Future Activities:
Work during year four will focus on the completion of Tasks VII – X as described in the proposal. Tasks include completion of the interface for survey implementation on Amazon MTurk, followed by pilot testing (Task V). Pilot tests will be used to make final adjustments to the questionnaire, MTurk interface and bid vector, before final survey implementation on MTurk (Task VI). We will also implement a subset of scenarios using a standard mail/online push-to-web format for comparison, as described in the proposal (Task VI). We will then proceed with data verification and Bayesian econometric analysis (Task VII), including evaluation of any differences between MTurk and push-to-web results (Task VIII).
Journal Articles:
No journal articles submitted with this report: View all 6 publications for this projectSupplemental Keywords:
Media: water, watersheds; Ecosystem Protection: ecosystem, indicators, aquatic, habitat; Public Policy: decision making, cost-benefit, non-market valuation, contingent valuation, survey, preferences, public good, Bayesian, willingness-to-pay; Disciplines: social science, economics, ecology, hydrology; Methods/Techniques: modeling, analytical, surveys; Geographic Areas: Northeast, EPA Region 1; Other: ecosystem service, choice modeling, choice experiment, nonuse value, welfare analysis, water quality.Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.
Project Research Results
- Final Report
- 2020 Progress Report
- 2019 Progress Report
- 2017 Progress Report
- 2016 Progress Report
- Original Abstract
1 journal articles for this project