numeraire_dataset.zones.clean.ccm_links_clean#

numeraire_dataset.zones.clean.ccm_links_clean(ccmxpf_linkhist: DataFrame, *, link_types: tuple[str, ...] = ('LU', 'LC'), link_prims: tuple[str, ...] = ('P', 'C')) → DataFrame[source]#

Tidy CRSP-Compustat links: primary, reliable gvkey<->permno links with valid date windows.

Keeps linktype in link_types (LU/LC) and linkprim in link_prims (P/C), maps to gvkey, permno, linkdt, linkenddt with an open link end filled to a sentinel far-future date.