Tit-for-Tat: When the participant changes the amount they send in the same direction as the other player, either increased, decreased, or no change.
Benevolent: When the participant increases the amount sent to the other player despite a decrease or no change in the amount sent by the other player.
Ambivalent: The participant does not change the amount they send despite increases or decreases in the amount sent by the other player.
Malevolent: The participant decreases the amount sent to the other player despite an increase or no change in the amount sent by the other player.
n = the current trial.