from otree.api import * doc = """ This is a prisoner's dilemma game with side payments as well as symmetric and asymmetric treatments """ class Constants(BaseConstants): name_in_url = 'sym_game_test' players_per_group = 2 num_rounds = 1 treatment = ['symmetric', 'asymmetric'] rich_role = 'Rich' poor_role = 'Poor' class Subsession(BaseSubsession): pass def creating_session(subsession: Subsession): import itertools treatments = itertools.cycle([True, False]) for g in subsession.get_groups(): g.treatment = next(treatments) class Group(BaseGroup): treatment = models.BooleanField( doc="Group", label="Assigned group", choices=[ [True, 'Asymmetric'], [False, 'Symmetric'] ] ) sp_amount = models.FloatField( choices=[0, 1, 2], doc="Amount sent by Country A", label="How many points do you want to transfer to player B?", ) sp_decision = models.BooleanField( blank=True, doc="Decision of Country B", label="Do you want to accept the transfer?", choices=[ [True, 'Accept'], [False, 'Reject'], ] ) class Player(BasePlayer): cooperate = models.BooleanField( label="I want to", choices=[ [True, 'contribute the points to the joint project'], [False, 'keep the points'], ] ) def other_player(player: Player): return player.get_others_in_group()[0] def set_payoffs(group: Group): p1 = group.get_player_by_role(Constants.poor_role) p2 = group.get_player_by_role(Constants.rich_role) if group.treatment: if group.sp_amount >= 1 and group.field_maybe_none('sp_decision') == 1: if p1.cooperate: if p2.cooperate: p1.payoff = 4 + group.sp_amount p2.payoff = 10 - group.sp_amount else: p1.payoff = 2 + group.sp_amount p2.payoff = 5 - group.sp_amount else: if p2.cooperate: p1.payoff = 5 + group.sp_amount p2.payoff = 6 - group.sp_amount else: p1.payoff = 3 + group.sp_amount p2.payoff = 3 - group.sp_amount else: if p1.cooperate: if p2.cooperate: p1.payoff = 4 p2.payoff = 10 else: p1.payoff = 2 p2.payoff = 5 else: if p2.cooperate: p1.payoff = 5 p2.payoff = 6 else: p1.payoff = 3 p2.payoff = 3 else: if group.sp_amount >= 1 and group.field_maybe_none('sp_decision') == 1: if p1.cooperate: if p2.cooperate: p1.payoff = 5 + group.sp_amount p2.payoff = 5 - group.sp_amount else: p1.payoff = 2 + group.sp_amount p2.payoff = 6 - group.sp_amount else: if p2.cooperate: p1.payoff = 6 + group.sp_amount p2.payoff = 2 - group.sp_amount else: p1.payoff = 3 + group.sp_amount p2.payoff = 3 - group.sp_amount else: if p1.cooperate: if p2.cooperate: p1.payoff = 5 p2.payoff = 5 else: p1.payoff = 2 p2.payoff = 6 else: if p2.cooperate: p1.payoff = 6 p2.payoff = 2 else: p1.payoff = 3 p2.payoff = 3 # PAGES class Roles(Page): pass class Sidepayments(Page): form_model = 'group' form_fields = ['sp_amount'] @staticmethod def is_displayed(player: Player): return player.role == Constants.rich_role class WaitforOffer(WaitPage): @staticmethod def is_displayed(player: Player): return player.role == Constants.poor_role class Decision(Page): @staticmethod def is_displayed(player: Player): return player.role == Constants.poor_role form_model = 'group' form_fields = ['sp_decision'] class Contribution(Page): form_model = 'player' form_fields = ['cooperate'] class ResultsWaitPage(WaitPage): after_all_players_arrive = set_payoffs class Results(Page): @staticmethod def vars_for_template(player: Player): opponent = other_player(player) return dict( opponent=opponent, same_choice=player.cooperate == opponent.cooperate, my_decision=player.field_display('cooperate'), opponent_decision=opponent.field_display('cooperate'), opponent_payoff=opponent.payoff, ) page_sequence = [Roles, Sidepayments, WaitforOffer, Decision, Contribution, ResultsWaitPage, Results]