The main hypotheses concern fundamental differences in giving decisions between the two protocols: The non-interactive protocol predicts intermediate payments if a subject has some distributional and altruistic concern for the recipient's material well-being. By contrast, Nash equilibria of the games induced by the interactive protocol are characterized by extremal payments (either full or null payments), and in particular by increased levels of zero-giving for low prices of redistribution.
Additional hypotheses can be tested by varying the 'price of redistribution' p, that is, the factor by which each unit of material payoff that is given up is multiplied and sent to the recipient: in the interactive protocol, the Nash equilibrium prediction is that the peak at null (full) decreases (increases) in p.
We do a standard economic experiment conducted online. Recruitment will be done through a pre-registered subject pool from Amazon's Mechanical Turk, as used by the Decision Science Laboratory of ETH Zurich. Earnings will include a fixed show-up fee, and a variable bonus that depends on decisions of the subjects. We will not exclude any specific set of subjects except for ones that took part in dictator game experiments in the last three months, and we will pay subjects based on the decisions they take during the experiment according to online experiments standards. We aim to run the study before January 2018.
We plan to run 5 sessions of two-times-both treatments involving 20 active decision-making participants per session per treatment = 200 active subjects per treatment, which leads to a total of 600 subjects (of which 200 are inactive "recipients" in one of the treatments).