Céline Nauges

Technology Adoption under Production Uncertainty: Theory and Application to Irrigation Technology

We propose a theoretical framework to analyze the conditions under which a farmer facing production uncertainty (due to a possible water shortage) and incomplete information will adopt a more efficient irrigation technology. A reduced form of this model is empirically estimated using a sample of 265 farms located in Crete, Greece. The empirical results suggest that farmers choose to adopt the new technology in order to hedge against production risk. In addition, we show that the farmers human capital also plays a significant role in the decision to adopt modern, more efficient irrigation equipment.

Long-run Study of Residential Water Consumption

The estimation of dynamic models and themeasure of long-run effects arerare in residential water demand studies. Weshow in this paper that a dynamicmodel of water consumption can be derived froma structural optimisation programsolved by local communities. Thisnonlinear model is estimated on asample of French municipalities and is foundasymptotically equivalent to a dynamic panel data model that is linear in theparameters. The latter includes anoriginal error-component structure that allowsfor a flexible heterogeneity pattern, including both the usual idiosyncraticeffect, and an additional individualeffect affected by a multiplicative time-varyingparameter. As usual GMM estimators for panel data are not consistent inthis case, we propose a new GMMprocedure that yields consistent and efficientestimates of short- and long-runprice elasticities (respectively −0.26 and−0.40).

The story of the moment: risk averse cypriot farmers respond to drought management

This article illustrates the importance of estimating risk preferences when evaluating water policy. Using agricultural production data from the Kiti region of Cyprus we estimate farmers’ risk preferences à la Antle (Journal of Business and Economic Statistics, 1, 192–201, 1983, American Journal of Agricultural Economics, 69, 509–22, 1987) and show sensitivity to higher order moments of profit, such as skewness. We show that farmers in the Kiti region are risk averse with risk premiums in the region of 20% of expected profit. We use these estimates to analyse the impact of a water quota from the perspective of three policy-makers who differ only in their understanding of farmers’ risk preferences. We show in the case of Kiti that policy-makers who model risk preferences incorrectly, that is, either; (a) assume risk neutrality or; (b) ignore down-side risk, wrongly predict the magnitude and direction of input responses and therefore the magnitude of welfare changes. This highlights the importance of accommodating preferences for higher order moments of profit in the evaluation of water policy.

Ex Post Evaluation of an Earmarked Tax on Air Pollution

In this paper we do an ex post evaluation of the French tax on air pollution. The revenues of this tax were redistributed to polluters in the form of subsidies to abatement technologies, and the policy is a typical example of an earmarked tax. We use a two-stage estimation procedure on an unbalanced panel data set of 226 plants from three industrial sectors that are some of the main contributors to nitrogen oxide and sulfur dioxide emissions. The results indicate that the overall environmental effectiveness of this particular tax/ subsidy scheme can be questioned. (JEL Q53, Q58)

Estimation de la demande domestique d'eau potable en France

Peu de travaux ont ete menes pour connaitre la demande en eau potable des menages en France. Nous proposons d’estimer la fonction de demande domestique en eau potable dans deux departements francais qui sont relativement similaires du point de vue des ressources en eau mais qui different en termes de conditions climatiques et de caracteristiques socio-demographiques. Des variables de type socio-economiques et des donnees meteorologiques ont en consequence ete introduites, outre les chiffres de consommation et de prix de l’eau, dans la fonction de demande. Les methodes econometriques appliquees sont des methodes specifiques de traitement de donnees de panel, ce qui permet d’eviter tout biais dans l’estimation des coefficients. L’estimation separee des deux echantillons fait apparaitre une elasticite-prix de la demande significative, estimee a – 0,08 et – 0,22 dans les deux departements. L’elasticite revenu n’est significative que dans un departement, ou elle est estimee a 0,01.

How Natural are Natural Monopolies in the Water Supply and Sewerage Sector? Case Studies from Developing and Transition Economies

Using data from the International Benchmarking NETwork database, the authors estimate measures of density and scale economies in the water industry in four countries (Brazil, Colombia, Moldova, and Vietnam) that differ substantially in economic development, piped water and sewerage coverage, and characteristics of the utilities operating in the different countries. They find evidence of economies of scale in Colombia, Moldova, and Vietnam, implying the existence of a natural monopoly. In Brazil the authors cannot reject the null hypothesis of constant returns to scale. They also find evidence of economies of customer density in Moldova and Vietnam. The results of this study show that the cost structure of the water and wastewater sector varies significantly between countries and within countries, and over time, which has implications for how to regulate the sector.

Evaluating Greening Farm Policies: A Structural Model for Assessing Agri-environmental Subsidies

This study uses a structural econometric model to evaluate the impacts of support from a European Union agri-environmental program designed to reduce nutrient pollution from agricultural land. Drawing on a representative sample of individual grain farms, we first quantify the effects of agri-environmental payments on farms’ decisions on land allocation and on fertilizer use. We then combine the predicted land allocation and fertilizer use with environmental production functions to quantify the impact on nutrient loading. Finally, we assess the monetary value of reduced nutrient pollution, drawing on a recent valuation study. (JEL Q53, Q58)

The Value of Water Connections in Central American Cities: A Revealed Preference Study

We estimate annualized values of access to home tap water in three cities in El Salvador, and marginal ‘barrios’ in four Guatemalan cities, using a hedonic price method for studying changes in capitalized home values from obtaining a water connection. A tap water connection is found to add from 10 per cent to 52 per cent to sales values of homes in our sample. The estimated mean values of gaining tap water access represent 1–5 per cent of real household income, differing by city and with generally higher values in El Salvador. On average this gain eliminates between 1 per cent and 3 per cent of the initial difference in real incomes between the groups of connected and unconnected households. We also find large differences in the value of a tap connection depending on the main source of non-tap water, with lowest values when the source is a private well in El Salvador.

Water Markets, Demand, and Cost Recovery for Piped Water Supply Services: Evidence from Southwest Sri Lanka

In many countries water supply is a service that is seriously underpriced, especially for residential consumers. This has led to a call for setting cost recovery policies to ensure that the tariffs charged for water supply cover the full cost of providing for the service. Yet, the question arises on how consumers will react to such price increases. The authors illustrate the impact of price increases on consumption of piped water through a study of the demand for water of piped and non-piped households using cross-sectional data from 1,800 households in Southwest Sri Lanka. The (marginal) price elasticity is estimated at -0.74 for households exclusively relying on piped water, and at -0.69 for households using piped water but supplementing their supply with other water sources, with no significant differences between income groups. Those households that depend on non-piped water sources have a time cost elasticity (as a proxy for price elasticity) of only -0.06. The authors discuss the implications of these results in terms of pricing policy.

The Impact of Perceptions in Averting-decision Models: An Application of the Special Regressor Method to Drinking Water Choices

Individuals are commonly surveyed about their perception or assessment of risk and these variables are often used to explain individuals’ actions to protect themselves against these risks. Perceptions appear as endogenous variables in traditional theoretical averting-decision models but, quite surprisingly, endogeneity of perceived risk is not always controlled for in empirical studies. In this article, we present different models that can be useful to the practitioner when estimating binary averting-decision models featuring an endogenous discrete variable (such as risk perception). In particular we compare the traditional bivariate probit model with the special regressor model, which is less well known and relies on a different set of assumptions. In the empirical illustration using household data from Australia, Canada, and France, we study how the perceived health impacts of tap water affect a household’s decision to drink water from the tap. Individuals’ perceptions are found to be endogenous and significant for all models, but the estimated marginal effect is sensitive to the model and underlying assumptions. The special regressor appears to be a valuable alternative to the more common bivariate probit model.