from otree.api import * doc = """ Simple trust game """ class C(BaseConstants): NAME_IN_URL = 'trust_simple' PLAYERS_PER_GROUP = 2 NUM_ROUNDS = 1 ENDOWMENT = cu(10) MULTIPLIER = 3 class Subsession(BaseSubsession): pass class Group(BaseGroup): sent_amount = models.CurrencyField( min=cu(0), max=C.ENDOWMENT, doc="""Amount sent by P1""", label="How much do you want to send to participant B?", ) sent_back_amount = models.CurrencyField( doc="""Amount sent back by P2""", label="How much do you want to send back?" ) class Player(BasePlayer): pass # FUNCTIONS def sent_back_amount_choices(group: Group): return currency_range(0, group.sent_amount * C.MULTIPLIER, 1) def set_payoffs(group: Group): p1 = group.get_player_by_id(1) p2 = group.get_player_by_id(2) p1.payoff = C.ENDOWMENT - group.sent_amount + group.sent_back_amount p2.payoff = group.sent_amount * C.MULTIPLIER - group.sent_back_amount # PAGES class Send(Page): form_model = 'group' form_fields = ['sent_amount'] @staticmethod def is_displayed(player: Player): return player.id_in_group == 1 class WaitForP1(WaitPage): pass class SendBack(Page): form_model = 'group' form_fields = ['sent_back_amount'] @staticmethod def is_displayed(player: Player): return player.id_in_group == 2 @staticmethod def vars_for_template(player: Player): group = player.group return dict(tripled_amount=group.sent_amount * C.MULTIPLIER) class ResultsWaitPage(WaitPage): after_all_players_arrive = set_payoffs class Results(Page): pass page_sequence = [Send, WaitForP1, SendBack, ResultsWaitPage, Results]