from otree.api import ( models, widgets, BaseConstants, BaseSubsession, BaseGroup, BasePlayer, Currency as c, currency_range ) doc = "\nEach player decides if to free ride or to volunteer from which all will\nbenefit.\n\nSee: Diekmann, A. (1985). Volunteer's dilemma. Journal of Conflict\nResolution, 605-610.\n" class Constants(BaseConstants): name_in_url = 'volunteer_dilemma' players_per_group = 3 num_rounds = 1 num_other_players = 2 general_benefit = c(100) volunteer_cost = c(40) instructions_template = 'volunteer_dilemma/instructions.html' class Subsession(BaseSubsession): pass class Group(BaseGroup): num_volunteers = models.IntegerField() def set_payoffs(self): players = self.get_players() self.num_volunteers = sum([p.volunteer for p in players]) if self.num_volunteers > 0: baseline_amount = Constants.general_benefit else: baseline_amount = c(0) for p in players: p.payoff = baseline_amount if p.volunteer: p.payoff -= Constants.volunteer_cost class Player(BasePlayer): volunteer = models.BooleanField(doc='Whether player volunteers', label='Do you wish to volunteer') Yes_No = models.IntegerField(choices=[[1, 'Yes. I have read and understood the above information, I choose to participate.'], [0, "No. I don't want to participate."]], widget=widgets.RadioSelect)