Central Bank

Properties

central-bank.py

class CentralBank(mesa.Agent):
    """A Central Bank agent."""

    def __init__(self, rate_data, unique_id, model):
        super().__init__(unique_id, model)
        
        self.breed = "Central Bank"
        self.period = 0 # Model run step.

        # Importing the rates dataframe into the class.
        self.rate_data = rate_data

        # (rb) Rate of interest in the economy. A percentage.
        self.base_rate = Decimal(0)
        self.base_rate_last_step = Decimal(0)

        # Current accounts
        # (INTcb) Interest received on Government bills held.
        self.interest_from_bills = Decimal(0)
        # (Fcb) Central bank profits to distribute to Government.
        self.profits = Decimal(0)

        # Capital accounts
        # (Bcbd) Government bills held. A residual, after household bill demands.
        self.bills_demanded = Decimal(0)
        # (Hs) High-powered money supplied to households.
        self.high_powered_money = Decimal(0)
        self.high_powered_money_last_step = Decimal(0)

Behaviour Comments and Functions

central-bank.py

def step(self):
    """
    1 Set the rate of interest on bills.
    2 Distribute profit on Government bills back to the Government. (t-1)
    3 Purchase government bills surplus to household requirements. (t)
    """
    # Record the interest rate before update in this step, if any.
    self.base_rate_last_step = self.base_rate

    # 1
    # Historic rates.
    self.base_rate = Decimal(float(self.rate_data['value'].iloc[self.period]))

    # 2
    # Connect with the government.
    government = self.model.get_agents_of_type(Government)[0]
    # Interest received from government.
    self.profits = abs(self.interest_from_bills)
    # Distribute profit to government.
    government.central_bank_profits += self.profits

    # 3
    """
    (Equation 5.15) ΔHs ≡ Hs - Hs₋₁ = ΔBcb

    The amount of cash money supplied by the central bank is simply equal to the
    amount of bills purchased by the central bank.
    """
    self.bills_demanded = self.high_powered_money - self.high_powered_money_last_step
    government.bills_issued_to_central_bank = self.bills_demanded

    # Complete Central Bank actions in this step.
    self.high_powered_money_last_step = self.high_powered_money

    # Model step counter used for real-world base rate data.
    self.period += 1