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T-LAB
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What T-LAB does and what it enables us to do
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Modeling of Emerging Themes
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Texts and Discourses as Dynamic Systems
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IDnumber
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Words and Lemmas
Bibliography

Frequency Threshold


During the pre-processing phase T-LAB computes a minimum frequency threshold to select words (or lemmas) for the automatic key-words list.

In any case, in order to guarantee the reliability of all statistical computations, the minimum T-LAB threshold is 4.


For this computation an algorithm documented in one of the books in the Bibliography is used (Bolasco, 1999). It requires the following steps:

- low frequency range detection; the range (starting from the minimum frequency -"1") is defined by the first "jump" in the growing occurrences values;

- threshold value choice. The threshold value, according to corpus sizes, corresponds to the minimum value in the first and in the second range decile (10% or 20%).