Account

Basic model of an account with optional interest

Diagram

Information

This information is part of the Business Simulation Library (BSL).

The output y reports the balance of an account that is increased or decreased by flows connected to the stock ports or at given rates (u_plus and u_minus respectively) if hasRateInputs = true. When there are interest payments (withInterest = true) positive and negative balances of the account will lead to interest earned and interest paid, respectively. The associated fractional rates can be given either as constants or as variable inputs.

Notes

Usually rates for deposits and withdrawals are given as separate, positive inputs. Using hasNetRateInput = true the rate of flow for the account can be given as a netRate using the connector u_plus only.

Fractional rates are assumed to be continuously compounding rates (→ForceOfInterest).

The Account is a more general structure than the widely known bathtub [6, pp.10f.]

Parameters (9)

initialBalance	Value: 0 Type: Money (CU) Description: Initial balance of the account
interestRatePlus	Value: unspecified Type: Rate (1/s) Description: Constant fractional interest rate for positive balances (optional)
interestRateMinus	Value: unspecified Type: Rate (1/s) Description: Constant fractional interest rate for negative balances (optional)
hasRateInputs	Value: true Type: Boolean Description: = true, if input connectors should allow giving transaction rates increasing/decreasing the balance of the account
hasNetRateInput	Value: false Type: Boolean Description: = true, if the rate of flow is given a net rate (u_plus only)
withInterest	Value: false Type: Boolean Description: = true, if positive and negative balances lead to interest earned or paid
hasConstantInterest	Value: true Type: Boolean Description: = true, if the optional interest rates are given as constant parameters
init	Value: modelSettings.init Type: InitializationOptions Description: Provide InitializationOptions (Free, FixedValue, SteadyState) (accountBalance.init)
strict	Value: true Type: Boolean Description: = true, if strict limits with noEvent(..) (positiveBalance.strict)

Connectors (9)

	inflow	Type: StockPort Description: Increasing the balance of the account
	outflow	Type: StockPort Description: Decreasing the balance of the account
	u_plus	Type: RealInput Description: Rate of inflow increasing the account (or net rate of flow)
	u_minus	Type: RealInput Description: Rate of outflow decreasing the account
	u_interestPlus	Type: RealInput Description: Fractional interest rate for positive balances (optional)
	u_interestMinus	Type: RealInput Description: Fractional interest rate for negative balances (optional)
	y_intEarned	Type: RealOutput Description: Interest earned (optional)
	y_intPaid	Type: RealOutput Description: Interest paid (optional)
	y	Type: RealOutput Description: Balance of the account (e.g., amount in the stock)

Components (15)

	modelSettings	Type: ModelSettings
	accountBalance	Type: InformationLevel Description: Balance of the account
	netFlow	Type: ExogenousChange Description: Net flow to or from the account
	negativeRate	Type: Gain Description: The rate of decrease is turned into a negative rate
	netRate	Type: Add_2 Description: Net rate of flow
	netRateInput	Type: PassThrough Description: Input u_plus net rate of flow
	interestPlus	Type: ConstantConverterRate Description: Constant rate of interest for positive balances
	interestMinus	Type: ConstantConverterRate Description: Constant rate of interest for negative balances
	positiveBalance	Type: ZeroIfNegative Description: Positive balance or zero
	negativeBalance	Type: ZeroIfNegative Description: Negative balance or zero
	invertedBalance	Type: Gain
	rateDecline	Type: Product_2 Description: Rate of decline
	interestPaid	Type: Decline Description: Interest decreasing the balance
	interestEarned	Type: Growth Description: Interest payments increasing the balance
	rateIncrease	Type: Product_2 Description: Rate of decline