calc_rank_of_last_retained_commonality_between

calc_rank_of_last_retained_commonality_between(first: Union[HereditaryStratigraphicColumn, HereditaryStratigraphicSpecimen], second: Union[HereditaryStratigraphicColumn, HereditaryStratigraphicSpecimen], confidence_level: float = 0.95) → int | None

Determine lower bound on generation of MRCA at confidence level.

How many depositions elapsed along the columns’ lines of descent before the last matching strata at the same rank between first and second?

Parameters

confidence_levelfloat, optional

With what probability should the true rank of the last commonality between first and second fall at or after the returned rank? Default 0.95.

Returns

int, optional

The number of depositions elapsed or None if no common ancestor is shared between the columns.

Notes

The true rank of the last commonality with second is guaranteed to never be after the returned rank when confidence_level < 0.5.