Environment, Development and Sustainability

, Volume 12, Issue 2, pp 179–193 | Cite as

Estimating willingness to pay with the stochastic payment card design: further evidence from rural Cameroon

  • William Munpuibeyi Fonta
  • Hyacinth E. Ichoku
  • Kanayo K. Ogujiuba


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.


Cameroon Field test SPC design Sample selection bias Heckman’s 2-step estimator 



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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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • William Munpuibeyi Fonta
    • 1
  • Hyacinth E. Ichoku
    • 1
  • Kanayo K. Ogujiuba
    • 1
  1. 1.Health/Environmental Economics Unit, Department of EconomicsUniversity of Nigeria NsukkaNsukkaNigeria

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