Experimental Design
Participants in the two experiments will be recruited through Prolific using a representative sample of the U.S. population. They will be redirected to the experimental platform developed using oTree (Chen et al., 2016) and randomly assigned to one treatment arm. All participants will first provide informed consent and then begin the experiment. At the end of the experiment, they will answer several demographic questions and draw a random number to determine whether they receive an additional bonus. The participation fee and any bonus payments will be distributed through Prolific within one week.
Experiment 1:
Experiment 1 involves budgetary decision tasks. Participants will complete 25 rounds of decision task in the risk preference domain (Choi et al., 2007, 2014) and 25 rounds in the social preference domain (Andreoni and Miller, 2002). The order of the two tasks will be randomized. In the risk preference domain, the participant allocates 100 points to two accounts, where the exchange rates between points and payoffs differ. She receives the payoff from one random account, selected with equal probability. For the social preference, the participant allocates 100 points between herself and another randomly matched agent. These points are converted into payoffs with distinct exchange rates for the two agents. Budget lines vary across rounds for both tasks. We will randomly select, on average, 1 out of every 30 participants to receive additional bonuses. For each of the selected participants, we will randomly select one round across total 50 rounds to realize her additional bonus.
Experiment 1 consists of three arms, examining whether dialogue structure affects economic rationality. In the first arm (Single-turn dialogue), all 25 rounds of decision are presented on the same page. In the second arm (Multi-turn dialogue), each page presents a new round of the task while retaining all previous questions and responses. In the third arm (Repeated single-turn dialogue), each page presents a new round of the task without retaining any previous questions or responses.
Experiment 2:
Experiment 2 involves five decision scenarios drawn from four tasks: the dictator game, the ultimatum game, the public goods game, and the bomb risk elicitation task. The order of the decision scenarios will be randomized. In each game, participants are required to make one decision, with the following exception—in the ultimatum game, the participants separately play the role of proposer, who proposes an allocation, and responder, who determines the minimum proposal they are willing to accept. Detailed descriptions of these tasks can be found in Mei et al. (2024). To avoid learning effects and simplify the analysis, we focus solely on the first round of decisions in each scenario. We will randomly select, on average, 1 out of every 30 participants to receive additional bonuses. For each of the selected participants, we will randomly select one game to realize her additional bonus.
Experiment 2 consists of two arms, examining whether answer format affects economic preferences. In the first arm (Open-ended answer format), participants may choose any value within the feasible range. In the second arm (Multiple-choice answer format), participants can select only one of the provided options. Given that the feasible choice sets in all scenarios except the public goods game range from 0 to 100, we discretize this range into 21 options in increments of 5. In the public goods game, where the feasible choice set ranges from 0 to 20, we retain 21 options and use increments of 1.