Experimental Design
Hypotheses
H1: Global redistribution policies help a political program to be preferred
The conjoint analysis asks respondents their preference between two political programs (they can also express indifference), with policies (or absence of policy) taken at random in each of five policy domains.
H1a: No positive effect of “Cut development aid” in the conjoint analysis.
H1b: Positive effect of “International tax on millionaires with 30% financing healthcare and education in low-income countries” in the conjoint analysis.
H2: Global issues are given substantial priority when allocating a budget
I ask respondents for their preferred allocation among five categories (there are two random branches: one where the five categories are fixed, one where they are taken at random out of 13 categories). I expect global issues to remain at a similar level of priority as previously found in Fabre et al. (2025), substantial though lower than most national issues. Namely, I expect an average allocation at two thirds of the average amount, that is 13.33% (66.66% of 20%).
H2: Allocation of at least 13.33% of the budget to each global issue.
H3: Global redistributive policies are supported by a majority
I test the support for various global redistributive policies, from realistic ones to radical ones.
When the questions are preceded by a treatment, the majority support is generally tested on the control group. I will also test an alternative specification where the control group is extended to treatment branches with no treatment effect (at a conservative 20% threshold).
H3a1, …, H3a10: Majority support for each realistic globally redistributive policy.
H3b: Majority support for the Global Climate Scheme.
H3c1, …, H3c9: Majority support for a global wealth tax, for a NCQG at least as high as the current amount ($26 billion in grant-equivalent), for a sustainable future, for both version a radical tax (on the global top 1% or top 3%), for global convergence in GDP per capita, for a global sustainability movement, for “my taxes should solve global problems”.
H4: Lower support but still majority support for international policies when fewer countries participate
I expect support to significantly decrease with partial (rather than universal) participation, though to remain in the relative majority.
H4a1, …, H4a6: Majority support for an international (non-global) wealth tax (two participation scenarios) and for an international climate scheme (four participation scenarios).
H4b1, …, H4b6: Lower support for an international policy under partial participation.
H5: Absence of warm glow
To test whether people support global redistribution only for as long as its implementation seems unlikely (H5a), I randomly treat respondents with information about ongoing negotiations on globally redistributive policies. Following the information, I expect their belief that global redistribution is likely to be higher. Warm glow would be identified if the number of realistic global redistribution policies supported were then lower. I will test the effect of information on support both directly and through a two-stage least squares model, with the belief in likelihood of global redistribution as the endogenous variable.
To test the effect of moral substitute (H5b), before the question on the support for the Global Climate Scheme, I randomly ask (or not) to the respondents how much they would like to donate to a reforestation charity, should they win the $100 lottery they are enrolled in. If the donation acts as a moral substitute, support should be lower for those who are offered this treatment.
H5a: Information increases the belief in the likelihood of global redistribution but does not reduce support for realistic global redistribution policies.
H5b: Being offered the possibility to donate to a reforestation charity (in case of lottery win) does not reduce support for the Global Climate Scheme.