calc_ranks_since_last_retained_commonality_with

calc_ranks_since_last_retained_commonality_with(focal: Union[HereditaryStratigraphicColumn, HereditaryStratigraphicSpecimen], other: Union[HereditaryStratigraphicColumn, HereditaryStratigraphicSpecimen], confidence_level: float = 0.95) → int | None

Determine generations since MRCA with particular confidence.

How many depositions have elapsed along the focal column’s line of descent since the last matching strata at the same rank between focal and other?

Returns None if no common ancestor is shared between focal and other.

Parameters

confidence_levelfloat, optional

With what probability should the true number of ranks since the last commonality with other be less than the calculated estimate? Default 0.95.

Notes

If confidence_level < 0.5, then the true number of ranks since the last commonality with other is guaranteed greater than or equal to the calculated estimate.