SEPS:PRISM | M. R. Dwyer
P03_Documented_Codetection_Counts

Each off-diagonal cell counts host identifiers with positive source records in both groups; the diagonal counts hosts with that group. We compute C = B transpose B for a documentary positive-record indicator B. Unrecorded taxa do not supply biological negatives. We therefore estimate neither odds ratios nor transmission edges from this matrix. Repeated records within a host contribute only once to group presence.

Source: Necropsy master workbook, Sheet1; exact source rows retained
Status: Source-linked descriptive analysis