Textbooks Readability THEORETICAL REVIEW

12 a Coleman Formulas Coleman formulas as explained by Dubay were introduced by Edmund B. Coleman. The formulas are used in a research project sponsored by the National Science Foundation. He published four readability formulas for general use; among other they are very important for predicting mean cloze scores percentage of correct cloze completions. Coleman was also the first who used cloze procedures as a criterion rather than the conventional multiple-choice reading tests or rankings by judges. The four formulas use different variables shown as the followings: 12 C = 1.29w – 38.45 C = 1.16w + 1.48s – 37.95 C = 1.07s + 1.18s + .76p – 34.02 C = 1.04w + 1.06s + .56p – .36prep – 26.01 Where: C = percentage of correct cloze completions; w = number of one-syllable words per 100 words s = number of sentences per 100 words p = number of pronouns per 100 words Prep = number of prepositions per 100 words b Bormuth Mean Cloze Formula The second one is the Bormuth Mean Cloze Formula. This formula is introduced by John Bormuth which intends to measure the degrees of reading power. This formula uses three variables namely number of words on the original Dale-Chall list of 3,000, average sentence length in words, and average word length in letters. The Bormuth Mean Cloze Formula is as follows: 13 R = .886593 – .083640 LETW + .161911 DLLW 3 – 0.021401 WSEN + .000577 WSEN 2 – .000005 WSEN 3 DRP = 1-R x 100 Where: R = mean cloze score LET = letters in passage X W = words in passage X DLL = Number of words in the original Dale-Chall list in passage X SEN = Sentences in passage X 12 William H. Dubay. The Principles of Readability, Costa Mesa, CA: Impact Information. 2004, p. 42. 13 Ibid., p. 44. 13 DRP = Degrees of Reading Power, on a 0 – 100 scale with 30 very easy to 100 very hard c Fry Readability Graph Fry Readability Graph is introduced by Edward Fry. One of the popular readability tests that use a graph. Then it is validated with comprehension scores of primary and secondary school materials and by correlations with other formulas. Directions of doing a measurement namely: 1 Select sample of 100 words. 2 Find y vertical, the average number of sentences per 100-word passage calculating to the nearest tenth. 3 Find x horizontal, the average number of syllables per 100-word sample. 4 The zone where the two coordinates meet shows the grade score. While scores that appear in the dark areas are invalid. 14 It can be seen in the following graph: Graph. 2.1 Fry’s Readability Graph 15 National Partnership for Women and Families describes the score shown by the intersection of x line horizontal and y line vertical of the Fry graph. The descriptions are: 1 4 th – 6 th grade means readable by most adults. 2 7 th – 8 th grade mean readable by half or more adults. 3 14 Dubay. Op. Cit., pp. 44 —46. 15 National Partnership for Women and Families. Fry Readability Formula; an Overview. 2009, p. 1.