Experimental Design
In total, we compare four experimental treatments (between subjects) that vary which information participants have before making a donation decision. The design is based on standard theories of giving which posit that donors care about the total amount received by a recipient (G), their personal income (x) and their donation (g) as well as the share of their impact (g/G). The weight of these variables depends on the donor type (i.e., their unknown utility function). In a minimal design, we provide subjects with information about g and x, as well as about an amount committed by a third party. This follows a design in Ottoni-Wilhelm et al (2017). In an expanded version of the design, we provide a further breakdown of these information variables and hence allow different giving types to express their preferences more fully. The main focus for identifying giving types is on two treatments where participants have to decide which information they want to gather (for free) prior to making a decision.
Within subjects the choice sets vary
- The amount committed by a third party
- The amount of the gift matched/rebated
- The total income participants can choose over
In total each participant will provide answers in 16 main choice sets with 6 possible allocations in each. We also include 8 filler tasks.