Presence/Absence coding

Presence-absence coding helps you transform lists of attributes (or species) to a dataset that can be analyzed using statistical procedures.

Why do we use presence/absence coding

In many domains, data are available as sets of lists of attributes (a list by statistical individual). It might be a list of pharmaceutical properties for a list of plants, or a list of occurrences of species in a biotope. These lists cannot be manipulated by most statistical tools, and therefore, they first need to be transformed into a presence/absence table, where each cell has a 0 if the attribute is absent and a 1 if the attribute is present.

Presence/Absence coding in XLSTAT

Converting a table of attributes into a table of presences/absences showing the frequencies of the various elements for each of the lists has never been easier. You simply need to select the table in the XLSTAT tool for Presence/Abcense coding and the new table will be generated instantly.

Below you can find an example of presence/absence coding. Based on a table of two lists containing various elements, a presence/absence coding summarizes the presence of the elements in each list.

List 1List 2
E1 E1 E2 E1 E3E3 E1 E4

Table with presence and absence coding:

 E1E2E3E4
List 11110
List 21011