• ALFRED BOTHE KPADE DOSSA Benin Center for Scientific Research and Innovation (CBRSI), University of Abomey-Calavi (UAC), Cotonou, Benin.
  • POKOUN DAME KOMBIENOU Benin Center for Scientific Research and Innovation (CBRSI), University of Abomey-Calavi (UAC), Cotonou, Benin.


contingent evaluation, agricultural soil conservation, selection, probit


Land degradation is an environmental problem that constitutes a serious threat and endangers food production and rural livelihoods. Thus, where water and wind erosion, reinforced by human activities, can have negative impacts on soils, there are methods to restore or maintain soil fertility in a context of financial constraints. (Dossa, 2016). The contingent evaluation method is the mathematical tool used to model the willingness to pay (CAP: WTP) of farm households to invest financially in soil conservation techniques in the commune of Kérou in the north-west and on the ADJA Plateau in the south-east of Benin. Its formalisation made it possible to calculate the average CAP E (CAP) on a sample by the following formula: E(CAP)=m(α/σ)/(β/σ). Thus, in estimating the average CAP using the probit model, the tobit model (Tobin, 1958) is tested by the two-step method of Heckman (1979) to control for selection bias in the sample of 385 farm households in Kérou and 267 on the ADJA Plateau. The results of the econometric regression give an average CAP of 1,260.92 FCFA/month/hectare for the adoption of SCTs (soil conservation techniques) in Kérou and 1,557 FCFA/month/hectare on the ADJA Plateau.


Alinsato, A.S. (2006): Analysis of the determinants of willingness to pay for soil conservation. – Faculty of Economics and Management, University of Abomey-Calavi 25p.

Amadou, I. (2008): Consent to pay consumers for healthy vegetables in urban and peri-urban areas: the case of southern Benin. – University of Abomey Calavi 85p.

Amemiya, T. (1981): Qualitative Response Models: A Survey. – Journal of Economic Literature 19 (4): 481-536.

Arrow, K., Solow, R., Portney, P.R., Radner, R., Schuman, H., (1993): Report of the NOAA panel on contingent valuation. – Federal Register 58(10): 4602- 4614

Avocè, V.F. (2012): Health costs of air pollution in the city of Cotonou in Benin. – University of Abomey-Calavi 245p.

Dato, P. Z. (2010): Policies for the sustainable management of non-renewable natural resources in Benin: the case of gravel exploitation in the municipality of Dogbo. – University of Abomey-Calavi 21p.

Dossa, A. (2016): Assessment and financing of environmental expenditures: case of willingness to pay for the conservation of agricultural soils in Kérou, Benin. – University of Abomey-Calavi 303p.

Garcia, S., Harou, P., Montagné, C., Stenger, A. (2009): Models for sample selection bias in contingent valuation: Application to forest biodiversity. – Journal of Forest Economics 15(1-2): 59-78.

Gbinlo, R. E. (2010): Organization and financing of household waste management in the cities of Sub-Saharan Africa: Case of the city of Cotonou in Benin. – University of Orleans 237p.

Haab, T.C., McConnell, K.E. (2003): Valuing Environmental and Natural Resources: The Econometrics of Non-Market Valuation (New Horizons in Environmental Economics series). – Edward Elgar Pub 352p.

Heckman, J. (1979): Sample Selection Bias as a Specification Error. – Econometrica 47(1): 153- 162.

Kombiénou, P.D. (2016): Influence of agricultural production systems on land use, soil fertility and agro-biodiversity in mountainous areas in the department of Atacora in Benin. – University of Abomey-Calavi 283p.

Maddala, G.S. (1983): Limited dependent and qualitative variables in econometrics. – Cambridge University Press 401p.

Mäler, K.G. (1974): Environmental Economics: A Theoretical Inquiry. – John Hopkins University Press 267p.

Marpsat, M., Trognon, A. (1992): Overview of the Logit model. – Journées de Méthodologie Statistique 32p.

Reveret, J.P., Charron, I., St-Arnaud, R.M. (2008): Reflections on methods for estimating the economic value of wildlife habitat loss. – AGECO Group for the Ministry of Natural Resources and Wildlife, Department of Socio-Economic Development, Partnerships and Education, Quebec 54p.

Tobin, J. (1958): Estimation of Relationships for Limited Dependent Variables. – Econometrica 26(1): 24-36.

Voltaire, L. (2011): Contingent valuation method and economic valuation of a nature reserve project in the Gulf of Morbihan (France). – University of Western Brittany 281p.

Yaya, S., Nouatin, G.S., Singbo, S.J. (2013): Community pre-financing: the willingness to pay of households for primary health care in the commune of Sèmè-Podji. – Department of Ouémé, Benin 7p.




How to Cite

DOSSA, A. B. K., & KOMBIENOU, P. D. (2021). STATISTICAL APPLICATION OF THE CONTINGENT EVALUATION FOR CONSERVATION OF AGRICULTURAL SOILS IN BENIN. Quantum Journal of Engineering, Science and Technology, 2(3), 1–11. Retrieved from