arch.bootstrap.StepM

class arch.bootstrap.StepM(benchmark: ndarray | DataFrame | Series, models: ndarray | DataFrame | Series, size: float = 0.05, block_size: int | None = None, reps: int = 1000, bootstrap: 'stationary' | 'sb' | 'circular' | 'cbb' | 'moving block' | 'mbb' = 'stationary', studentize: bool = True, nested: bool = False, *, seed: int | Generator | RandomState | None = None)[source]

StepM multiple comparison procedure of Romano and Wolf.

Parameters:
benchmark: ndarray | DataFrame | Series

T element array of benchmark model losses

models: ndarray | DataFrame | Series

T by k element array of alternative model losses

size: float = 0.05

Value in (0,1) to use as the test size when implementing the comparison. Default value is 0.05.

block_size: int | None = None

Length of window to use in the bootstrap. If not provided, sqrt(T) is used. In general, this should be provided and chosen to be appropriate for the data.

reps: int = 1000

Number of bootstrap replications to uses. Default is 1000.

bootstrap: 'stationary' | 'sb' | 'circular' | 'cbb' | 'moving block' | 'mbb' = 'stationary'

Bootstrap to use. Options are ‘stationary’ or ‘sb’: Stationary bootstrap (Default) ‘circular’ or ‘cbb’: Circular block bootstrap ‘moving block’ or ‘mbb’: Moving block bootstrap

studentize: bool = True

Flag indicating to studentize loss differentials. Default is True

nested: bool = False

Flag indicating to use a nested bootstrap to compute variances for studentization. Default is False. Note that this can be slow since the procedure requires k extra bootstraps.

seed: int | Generator | RandomState | None = None

Seed value to use when creating the bootstrap used in the comparison. If an integer or None, the NumPy default_rng is used with the seed value. If a Generator or a RandomState, the argument is used.

Notes

The size controls the Family Wise Error Rate (FWER) since this is a multiple comparison procedure. Uses SPA and the consistent selection procedure.

See [1] for detail.

See also

SPA

References

Methods

compute()

Compute the set of superior models.

reset()

Reset the bootstrap to it's initial state.

Properties

superior_models

List of the indices or column names of the superior models