Center for Environmental Economics - Montpellier - Monthly Publications feed

Deforestation and retail prices of Brazilian beef: a preregistered product-level econometric analysis

2026-10-02 10:58:08

Tereza da Silva Jacqueline, Guye Valentin, de Carvalho Aline Martins, Garcia Andrea, Cammelli Federico, Moran Dominic, de Oliveira Silva Rafael, zu Ermgassen Erasmus
Lancet Planetary Health
à paraître

Background Cattle ranching is the leading proximate driver of deforestation in Brazil. Efforts to eradicate deforestation could incur a trade-off between forest conservation and agricultural production, as conservation constrains the supply of new agricultural land and requires investments in traceability and improved agricultural production, potentially negatively affecting consumer welfare through increased retail prices. We estimated the effect of deforestation on consumer prices using supply chain data for 2980 beef products in Brazil. Methods We investigated the effect of deforestation on retail prices using a regression model with neighbourhood fixed effects and covariates, including sanitary inspection level, product type, distance from meatpacker to retail store, supply chain monitoring, and retail store size. The model was informed by a directed acyclic graph and the analysis plan was preregistered. Findings We found no evidence that deforestation rates in regions where beef products were sourced affected retail price (R$-1

Valuing undesirable waiting time: Evidence from a real-incentive lab experiment

2026-09-22 15:06:36

Beaud Mickael, Blayac Thierry, Priour Elven, Rosaz Julie, Stéphan Maïté
Journal of Behavioral and Experimental Economics 124: 102627
2026

We study how individuals value reductions in passive and undesirable waiting time using a real-incentive laboratory experiment. Participants were required to endure enforced inactivity – no phone, no reading, no conversation – and could pay to reduce the waiting time. By varying both the size of the time reduction (within-subject) and the initial waiting duration (between-subjects), we elicit willingness to pay (WTP) for time savings and compute the implied value of time (VOT) in euros per hour. We find that WTP is positive on average but increases less than proportionally with the amount of time saved. As a result, the VOT decreases with both the size of the time reduction and the initial waiting time. These findings highlight reference dependence and diminishing marginal sensitivity to time savings, challenging the assumption of a constant VOT commonly used in transport appraisal. Our results support a more context-sensitive approach to time valuation.

Improving households biowaste management: An attitudes and perceptions based typology to identify targeted policy levers

2026-09-22 15:06:34

Garnier Suzon, Guillou Célestine, Aissani Lynda, Ibanez Lisette, Mathias Jean-Denis, Tremier Anne, Blazy Jean-Marc, Barlagne Carla
Cleaner Waste Systems 15: 100578
2026

Small island territories such as Guadeloupe face acute challenges in solid waste management and limited recycling of organic residues. Strengthening better household biowaste management is essential to advancing a circular bioeconomy and reducing waste management costs. Composting offers a locally adapted solution that can enhance soil quality, support domestic resource valorization, and divert organic waste from landfills. However, adoption remains limited by behavioural and infrastructural barriers. This study investigates the attitudinal and sociodemographic determinants shaping household biowaste sorting and composting practices in Guadeloupe. The research draws on the COM-B model, which conceptualises behaviour as the interaction of capability, opportunity, and motivation. It also uses the Behaviour Change Wheel to identify key behavioural drivers and design targeted interventions for home and community composting. A household survey (n = 241) was conducted, and behavioural determinants were analysed using binomial probit modelling, principal component analysis, and hierarchical cluster analysis. Results show that physical constraints, such as lack of space and psychological barriers, including perceived complexity and forgetfulness, are the most significant obstacles to composting. Environmental motivation alone is insufficient to induce behavioural change. Three household profiles were identified: indifferent households, motivated and practising households, and motivated but constrained households. Recommendations of targeted policy levers are proposed for each profile to better foster circularity in biowaste management. The study highlights the importance of integrating behavioural insights into circular bioeconomy policies. Differentiated strategies combining education, incentives, and infrastructural support can effectively enhance domestic composting and organic resource recovery in Guadeloupe.

No effect of endowment risk on dictator giving in the lab

2026-10-05 14:34:19

Beaud Mickael, Sun Yujiang, Willinger Marc
Economics Letters 259: 112774
2026

While various models of inequality aversion predict different effects of background risk on giving, empirical evidence remains mixed. This study presents a laboratory experiment using a modified dictator game to examine whether exposure to an additive, zero-mean background risk affecting endowments influences giving behavior. Our results show that such exposure does not significantly affect average donation amounts, the likelihood of giving nothing, or the tendency to split resources equally. These findings are consistent with ex ante inequality concerns under risk neutrality; however, overall, our experimental data do not support the behavioral predictions implied by purely ex post inequality aversion.

When air pollution meets comorbidities: evidence on the causal effect of PM2.5 on COVID-19 hospitalizations and deaths

2026-10-02 10:58:06

Morvan Carla, Lepeule Johanna, Lavaine Emmanuelle
International Journal of Epidemiology 55
2026

Abstract Background Despite growing evidence on the health effects of air pollution, few studies have examined its impact on COVID-19 hospitalizations and deaths, and none have explicitly accounted for preexisting comorbidities in a causal framework. This study addresses this gap by investigating the relationship between PM2.5 exposure and COVID-19 severity. We place particular emphasis on the role of comorbidities, which can increase vulnerability to COVID-19 and may interact with air pollution exposure. Methods We use an exhaustive dataset covering the entire French territory over 2020–1, totaling more than 3.5 million weekly observations. The data include information on COVID-19 mortality and hospitalizations, disaggregated by age, sex, and municipality, along with detailed records on preexisting conditions. To address endogeneity, we employ a two-stage least squares approach, using wind direction as an instrument for local PM2.5 concentrations. Results We find no significant effect of PM2.5 exposure on COVID-19 mortality or hospitalizations among individuals without preexisting conditions. However, when accounting for comorbidities, a 10 μg/m3 increase in PM 2.5 was associated with higher COVID-19 mortality rates (1.5 per 100 000, 95% CI: 0.8–2.2), particularly among patients with respiratory (0.9 per 100 000, 95% CI: 0.4–1.4), and cardiovascular diseases (0.6 per 100 000, 95% CI: 0.1–1.1). Conclusions These findings underscore the importance of incorporating comorbidities when assessing the health effects of air pollution during a pandemic. Our results also show that the effects of PM2.5 are driven by the oldest age groups, who are both more vulnerable to COVID-19 and more likely to have comorbidities.