Conference Agenda

Flight-booking websites, such as Google Flights and Skyscanner, increasingly display estimated CO2 emissions for flight itineraries, but little is known about whether this information affects booking decisions. We study how emissions disclosure affects consumers’ flight choices using US domestic flight data from 2018 to 2022 and a discrete-choice model and find that it increases consumers’ sensitivity to flight emissions. In our preferred specification, the absolute value of the emissions elasticity of demand increases from 0.23 in the predisclosure period to 0.28 in the period following the first disclosure. Expressed in willingness-to-pay (WTP) terms, the implied WTP for emissions reductions is $33 per ton higher in the postdisclosure period. Counterfactual simulations suggest that mandating emissions disclosure across all flight-booking platforms would further strengthen consumers’ responsiveness to emissions information.

Discrete choice experiments (DCEs) typically elicit a single “best” alternative per choice task, mirroring market settings in which only one chosen option is observed. Alternative elicitation formats—such as Best–Worst and Best–Best—collect additional preference information per task and are often motivated by gains in statistical efficiency. Yet efficiency gains require that multi-stage responses be behaviourally consistent and that the elicitation protocol not distort choice behaviour. We provide a systematic split-sample comparison of three elicitation formats—Best-only, Best–Worst, and Best–Best—in a DCE valuing peatland restoration outcomes in Scotland. Respondents were randomly assigned to treatments that differ only in the elicitation protocol, while the choice tasks and experimental design were held constant. Using mixed logit models estimated in preference space (with treatment-specific scale) and willingness-to-pay space, we test two questions. First, does the elicitation format affect first-best choices, even when the first question is identical across treatments? Second, are preferences recovered from follow-up responses equivalent when the follow-up elicits the “worst-of-two” versus the “best-of-two,” which are informationally equivalent in theory? We find that (i) first-best preferences are not invariant to the elicitation format—consistent with an observer effect—and (ii) follow-up responses reveal format-dependent preference information, including systematic differences between worst-of-two and best-of-two framing. The results caution against treating ranked-elicitation formats as an “insurance strategy” for small samples and have direct implications for welfare measurement and DCE design.

We investigate whether individuals discount delayed environmental rewards differently from delayed monetary rewards. Using a contingent valuation experiment with 1,850 respondents we elicit willingness to pay (WTP) for restoring eelgrass meadows in the Malmö port, Sweden, under three alternative time horizons for the same level of biodiversity recovery (2, 10, and 18 years). The same respondents also completed an analogous WTP task for monetary outcomes, allowing a direct comparison of individual discount factors across domains. Based on the WTP data, we estimate implicit discount factors and rates. We find a domain-specific term structure of discounting: annual discount factors across two equal 8-year intervals are very similar for the monetary domain (around 4.5%), whereas in the environmental domains the discount rate is substantially higher when the same biodiversity improvement is shifted from 10 to 18 years (10%) rather than from 2 to 10 years (4.5%). This implies greater impatience for environmental outcomes than for monetary ones in the more distant future —contrary to previous studies that often find overall lower environmental discount rates.