Automatic Settings

When this option is selected in the subsequent analyses the Key-Terms used will be chosen automatically by T-LAB.

The automatic list includes up to 3,000 lexical units which belong to the category of content words: nouns, verbs, adjectives and adverbs.

The selection criterion varies according to the kind of file analysed.

If the corpus is a single text T-LAB simply selects the lexical units with the highest occurrence values.

If the corpus is made up of two or more texts T-LAB uses the following algorithm:

· it selects the words with occurrence values higher than the minimum threshold;
· it computes the TF-IDF or applies the chi-square test to all the crosses of each selected word for all the texts being analysed (N.B.: In the case of chi square test, the maximum number of text allowed is 500);
· it selects the words with the TF-IDF or chi-square highest values, that is those words that, in the corpus, make the difference.

You can check the list of T-LAB key-terms by using the function Memo.