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Frat5 Curves

Frat5Curve

Bases: Named

FRAT5 = Fare Ratio at which 50% of customers will buy up to the higher fare.

Source code in passengersim/config/frat5_curves.py 
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class Frat5Curve(Named, extra="forbid"):
    """
    FRAT5 = Fare Ratio at which 50% of customers will buy up to the higher fare.
    """

    curve: dict[int, float]
    """Define a Frat5 curve.

    To be consistent with the econometric interpretation of the Frat5 curve,
    the values should increase as the keys (DCPs, e.g. days to departure) decrease.
    This implies that average willingness to pay increases as the departure date
    approaches.

    Example
    -------
    ```{yaml}
    - name: curve_C
      curve:
        63: 1.4
        56: 1.4
        49: 1.5
        42: 1.5
        35: 1.6
        31: 1.7
        28: 1.8
        24: 1.9
        21: 2.3
        17: 2.7
        14: 3.2
        10: 3.3
        7: 3.4
        5: 3.4
        3: 3.5
        1: 3.5
    ```
    """

    max_cap: float = 10.0
    """
    Maximum Q-equivalent demand implied by any unit of demand in any fare class.

    This cap is applied only on the creation of Q-equivalent demand that occurs
    at the end of each DCP, and is not used in any RM step.
    """

    @field_validator("curve")
    def _frat5_curves_accumulate(cls, v: dict[int, float], info: ValidationInfo):
        """Check that all curve values do not decrease as DCP keys decrease."""
        sorted_dcps = reversed(sorted(v.keys()))
        i = 0
        for dcp in sorted_dcps:
            assert (
                v[dcp] >= i
            ), f"frat5 curve {info.data['name']} moves backwards at dcp {dcp}"
            i = v[dcp]
        return v

curve instance-attribute 

curve: dict[int, float]

Define a Frat5 curve.

To be consistent with the econometric interpretation of the Frat5 curve, the values should increase as the keys (DCPs, e.g. days to departure) decrease. This implies that average willingness to pay increases as the departure date approaches.

Example 
- name: curve_C
  curve:
    63: 1.4
    56: 1.4
    49: 1.5
    42: 1.5
    35: 1.6
    31: 1.7
    28: 1.8
    24: 1.9
    21: 2.3
    17: 2.7
    14: 3.2
    10: 3.3
    7: 3.4
    5: 3.4
    3: 3.5
    1: 3.5

max_cap class-attribute instance-attribute 

max_cap: float = 10.0

Maximum Q-equivalent demand implied by any unit of demand in any fare class.

This cap is applied only on the creation of Q-equivalent demand that occurs at the end of each DCP, and is not used in any RM step.