Abstract
This study reports new empirical findings of the field test of the stochastic payment card (SPC) design recently proposed by Wang (Contingent valuation of environmental resources: A stochastic perspective, 1997a; Journal of Environmental Economics & Management 32:219–232, 1997b). The purpose is to see how well this new contingent valuation method (CVM) elicitation format works in different cultural contexts, and what lessons can be drawn in general regarding its usefulness in environmental valuation. The survey is designed to estimate willingness to pay (WTP) values for an intended community-based environmental project in rural Cameroon (i.e., the control of malaria using larvivorous eating fish species). In order to estimate the bid function, Heckman’s 2-step method is used to detect, and if possible, correct for sample selection bias, an issue overlooked by the 2-step modeling approach proposed by Wang (1997a). The results suggest generally that in the presence of sample selection bias, Heckman’s 2-step estimates are more efficient and reliable for the public project in question than Wang’s proposed 2-stage modeling approach.
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Notes
The main function of the dam is to increase the volume of water into the River Sanaga that supplies Cameroon with hydroelectricity. The dam is located in the Bamendjim community of the Western Province of Cameroon; however, the artificial lake is found in the Ndop area of the Ngoketunjia Division, North West Province, Cameroon.
True zeros correspond to where respondents find the amenity valueless, whereas “protest” zeros, according to Freeman (1993, p. 187), occur when respondents reject some aspects of the constructed market scenario by reporting a zero value even though they place a positive value on the amenity or resource being valued.
The study area, which is one of the 13 communities that make up the entire Ndop clan located in the Ngoketunjia Division of the North West Province, Cameroon. By 2004, Bambalang comprised fifteen quarters with a population estimate of approximately 16,000 inhabitants living some few kilometers away from the lake.
More than 260 species of larvae eating fishes have been used in more than 40 countries in the world to combat 35 different species of mosquitoes (World Environmental Library: Document). Two commonly used species are the Gambusia affinis and Guppy (Poecilia reticulate). They are prolific mosquito breeders and can each consume 200–300 mosquito larvae per day. They are also surface feeders and hence are suitable for consuming floating mosquitoes.
Called community-led financing schemes because a greater part of these schemes are financed from funds raised within the communities. The methods of financing may include user fees, repayment/insurance scheme, commercial schemes, fund rising, and in-kind contributions.
Selected following answers to open-ended questions used in the pilot survey.
Those who always answer “definite no and probably no” or “definite no,” “probably no,” and “not sure” to all the offered prices on the card design.
According to NOAA’s first guideline for conducting CVM surveys, if a single dichotomous question of the yes/no type is used to elicit valuation questions, a total sample size of 1,000 respondents will limit the sampling error to about 3% plus or minus on a single dichotomous question, assuming simple random sampling (Arrow et al. 1993, p. 46).
At the time of the survey, one US dollar equalled 490 CFA francs.
Given the negligible percentage of true zero bidders in the dataset, we did not consider this group in the analysis.
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Acknowledgements
The authors are extremely grateful to E. Strazzera and H. Wang for their invaluable guidance and assistance while preparing the final Dissertation from which this paper is derived. The helpful suggestions and comments from Prof. A. O. Okore (Late) and Apia E. Okorafor are gratefully acknowledged. We equally thank the Editor and an anonymous referee whose comments and suggestions have helped greatly to improve the quality of this paper. The study from which this paper is derived was generously funded by the African Economic Research Consortium (AERC). However, the views and opinions expressed in the article are those of the authors and not of the consortium. Usual caveat applies.
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Except of the SPC WTP scenario
Except of the SPC WTP scenario
As you may be aware, malaria is a major health problem in Bambalang. The main cause of this is the site and location of the Bamendjim dam. The government is facing serious financial crisis, and therefore, lacks money to eradicate the disease in the community. One option that is quite feasible is for the members of this community to come together and initiate a kind of scheme called community-led financing scheme. It is what is done in most communities in the world to fight against poverty and diseases eradication. For the scheme to be implemented and managed, each member is expected to contribute financially or in kind for a stipulated period into a central fund managed by elected community members. If this is done, the money will be used to buy and nurse mosquito larvae eating fish species that can be used to completely eradicate mosquitoes in Bambalang.
Several advantages would accrue to Bambalang if the scheme is implemented. Some of these advantages include reduced medical expenditures for households, enhancement in the learning ability of children, increased life expectancy, reduction in adult and infant mortality rates, increased productivity of households, more savings, increased fish productivity, employment opportunities in the form of fish farming, and most importantly, the scheme would attract development assistance from several donor agencies, which implies more access to funds for the community members.
Please it is very important to first think of your monthly income and expenditure on other basic items before suggesting which price your household would be WTP to support the realization of the malaria control scheme. Suppose the amounts given on the left hand column (in Francs CFA) indicate an increase in household expenditure (assuming for say four times in a year), to help finance the implementation of the scheme in Bambalang, how likely is it you would vote for a plan to help implement the new scheme in Bambalang?
Enumerator: instruct respondent to circle an answer for each of the six prices
Cost to household (in franc CFA) | Definitely no (%) | Probably no (%) | Not sure (%) | Probably yes (%) | Definitely yes (%) |
|---|---|---|---|---|---|
0 | 0 | 25 | 50 | 75 | 100 |
200 | 0 | 25 | 50 | 75 | 100 |
400 | 0 | 25 | 50 | 75 | 100 |
600 | 0 | 25 | 50 | 75 | 100 |
800 | 0 | 25 | 50 | 75 | 100 |
1000 | 0 | 25 | 50 | 75 | 100 |
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Fonta, W.M., Ichoku, H.E. & Ogujiuba, K.K. Estimating willingness to pay with the stochastic payment card design: further evidence from rural Cameroon. Environ Dev Sustain 12, 179–193 (2010). https://doi.org/10.1007/s10668-009-9188-1
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DOI: https://doi.org/10.1007/s10668-009-9188-1