Essence.Readability.dale_chall

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dale_chall(doc)

Calculates the Dale-Chall readability score. that provides a numeric gauge of the comprehension difficulty that readers come upon when reading a text. It uses a list of 3000 words that groups of fourth-grade American students could reliably understand, considering any word not on that list to be difficult.

ScoreNotes
4.9 or lowereasily understood by an average 4th-grade student or lower
5.0–5.9easily understood by an average 5th or 6th-grade student
6.0–6.9easily understood by an average 7th or 8th-grade student
7.0–7.9easily understood by an average 9th or 10th-grade student
8.0–8.9easily understood by an average 11th or 12th-grade student
9.0–9.9easily understood by an average 13th to 15th-grade (college) student