"Associates" is the name given to key-words associated with a key key-word.
The point of it…
The idea is to identify words which are commonly associated with a key key-word, because they are key words in the same texts as the key key-word is. An example will help.
Suppose the word wine is a key key-word in a set of texts, such as the weekend sections of newspaper articles. Some of these articles discuss different wines and their flavours, others concern cooking and refer to using wine in stews or sauces, others discuss the prices of wine in a context of agriculture and diseases affecting vineyards. In this case, the associates of wine would be items like Chardonnay, Chile, sauce, fruit, infected, soil, etc.
The listing shows associates in order of frequency. A menu option allows you to re-sort them.
Settings
You can set a minimum number of text files for the association procedure, in the database settings:

Minimum texts
The screenshot settings will only process those key-key-words which appear in at least 3 text files.
Statistic
Choose the mutual information statistic you prefer, apart from Z score which uses a span (here we're using the whole text).
Minimum strength
This will only show associates which reach at least the strength set here, eg. 3.000.
See also: definition of associate.
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