Fig. 3.

Distributions of choices of ChatGPT-4, ChatGPT-3, and human subjects in each game: (A) Dictator; (B) Ultimatum as proposer; (C) Ultimatum as responder; (D) Trust as investor; (E) Trust as banker; (F) Public Goods; (G) Bomb Risk; (H) Prisoner’s Dilemma. Both chatbots’ distributions are more tightly clustered and contained within the range of the human distribution. ChatGPT-4 makes more concentrated decisions than ChatGPT-3. Compared to the human distribution, on average, the AIs make a more generous split to the other player as a dictator, as the proposer in the Ultimatum Game, and as the Banker in the Trust Game, on average. ChatGPT-4 proposes a strictly equal split of the endowment both as a dictator or as the proposer in the Ultimatum Game. Both AIs make a larger investment in the Trust Game and a larger contribution to the Public Goods project, on average. They are more likely to cooperate with the other player in the first round of the Prisoner’s Dilemma Game. Both AIs predominantly make a payoff-maximization decision in a single-round Bomb Risk Game. Density is the normalized count such that the total area of the histogram equals 1.