Question: How accurate are readability formulas?
Answer: “There are easy ways to get a readability estimate. [Italics are in the original document.] …. If you don’t have a computer available, use Edward Fry’s graph. It requires little more than counting the numbers of sentences and syllables in some text samples…. But don’t forget that all graphs and formulae are imperfect in determining how easy or difficult a passage or book may be. Factors such as student interest and background in a topic, how clear the author’s writing style is, how fully the author explains the topic, and whether graphic aids are included, etc., are not measured. Formulae are only rough estimates of difficulty.” Pp. 923-924.
Fry readability formula
From Wikipedia, the free encyclopediaSee the Internet for a copy of the graph.
The Fry readability formula (or Fry readability graph) is a readability metric for English texts, developed by Edward Fry.
The grade reading level (or reading difficulty level) is calculated by the average number of sentences (y-axis) and syllables (x-axis) per hundred words. These averages are plotted onto a specific graph; the intersection of the average number of sentences and the average number of syllables determines the reading level of the content.
The formula and graph are often used to provide a common standard by which the readability of documents can be measured. It is sometimes used for regulatory purposes, such as in healthcare, to ensure publications have a level of readability that is understandable and accessible by a wider portion of the population.
To calculate a grade level score:
Randomly select three separate 100 word passages. (Count every word including proper nouns, initializations, and numerals.)
- Count the number of sentences in each 100 word sample (estimate to nearest tenth).
- Count the number of syllables in each 100 word sample. (Each numeral is a syllable. For example, 2007 is 5 syllables -- two-thou-sand-se-ven -- and one word.)
- Plot the average sentence length and the average number of syllables on the graph.
- The area in which it falls is the approximate grade