PathBidPriceTracer¶

class passengersim.tracers.bid_price.PathBidPriceTracer(path_ids: list[int], *, priority: int = 1)[source]¶

Bases: _BidPriceTracer

A daily tracer that records the bid prices for specified paths.

At each day, the total bid price for each tracked path is captured and accumulated using a Welford online estimator, so that the mean and standard deviation across simulation samples can be computed efficiently.

Initialize the tracer.

Parameters:

path_ids : list[int]¶

IDs of the paths whose bid prices should be tracked.

priority : int, optional¶

Callback priority. Lower values run first. Defaults to 1.

Methods

__init__(path_ids, *[, priority])	Initialize the tracer.
attach(sim)	Attach a fresh instance of this tracer to sim as a daily callback.
finalize()	Aggregate accumulated Welford statistics into a tidy DataFrame.
fresh()	Return a new, empty tracer of the same type and configuration.
reset()	Reset all accumulated bid-price data to empty Welford accumulators.

Attributes

name	Identifier used to store results in SimulationTables.callback_data.
bid_prices	Nested mapping of entity-ID → days-prior → Welford accumulator.

name : str = 'path_bid_prices'¶

Identifier used to store results in SimulationTables.callback_data.

__init__(path_ids: list[int], *, priority: int = 1)[source]¶

Initialize the tracer.

Parameters:

path_ids : list[int]¶

IDs of the paths whose bid prices should be tracked.

priority : int, optional¶

Callback priority. Lower values run first. Defaults to 1.

attach(sim: Simulation) → None¶

Attach a fresh instance of this tracer to sim as a daily callback.

Parameters:

sim : Simulation¶

The simulation to attach the callback to.

finalize() → DataFrame¶

Aggregate accumulated Welford statistics into a tidy DataFrame.

Returns:

pd.DataFrame – A DataFrame with a MultiIndex of (statistic, days_prior) containing mean and sample standard deviation bid prices for each tracked entity. The DataFrame attrs n_trials and aggregation_process are set for downstream aggregation.

fresh() → _BidPriceTracer¶

Return a new, empty tracer of the same type and configuration.

Returns:

_BidPriceTracer – A freshly initialized tracer of the same concrete type, with the same IDs and priority but no accumulated data.

reset() → None¶

Reset all accumulated bid-price data to empty Welford accumulators.

bid_prices : dict[int, dict[int, Welford]]¶

Nested mapping of entity-ID → days-prior → Welford accumulator.