الگوریتم MEAD

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الگوریتم MEAD چه جوری عمل می کند؟
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Centroid-based methods: This type of methods ranks sentences
by computing their salience using a set of features. For example,
MEAD (Radev, Jing, Stys, & Tam, 2004) is a typical centroidbased
algorithm which extracts sentences according to three
parameters, i.e. centroid value, positional value, and first-sentence
overlap. The centroid value of a sentence is computed
as the average cosine similarity between the sentences and
the rest of the sentences in the document collection. The positional
value is computed as follows: the leading sentence is
assigned score 1 and the score decreases by 1=n for each sentence,
where n is the number of sentences in these documents.
The overlap value is computed as the cosine similarity between
a sentence and the first sentence in the same document. Then
the three values are linearly combined with equal weights.

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