Table A2.
Coh-Metrix Indices as a Function of Test Level
| Index | Level
|
p | Cohen’s d | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Purple | Brown | Blue | ||||||||
|
|
|
|||||||||
| M | SD | M | SD | M | SD | P v Br | P v Bl | Br v Bl | ||
| Number of sentences | 17.67 | 6.41 | 21.67 | 9.42 | 23.17 | 14.85 | .667 | −0.50 | −0.48 | −0.12 |
| Number of words | 183.67 | 51.92 | 306.00 | 90.52 | 293.67 | 125.46 | .076 | −1.66 | −1.15 | 0.11 |
| Words per sentence | 10.79 | 2.48 | 15.04 | 3.61 | 14.23 | 3.33 | .079 | −1.37 | −1.17 | 0.23 |
| Syllables per word | 1.28 | 0.08 | 1.42 | 0.12 | 1.42 | 0.08 | .028 | −1.37 | −1.75 | 0.00 |
| Flesch Reading Ease | 87.89 | 8.86 | 71.65 | 12.65 | 72.48 | 8.37 | .023 | 1.49 | 1.79 | −0.08 |
| Celex Word Frequency | 2.26 | 0.14 | 2.22 | 0.24 | 2.18 | 0.16 | .755 | 0.20 | 0.53 | 0.20 |
| Content Word Concreteness | 439.21 | 29.13 | 421.64 | 11.60 | 421.09 | 18.25 | .265 | 0.79 | 0.75 | 0.04 |
| Connective to Verb Ratio | 0.39 | 0.13 | 0.52 | 0.30 | 0.62 | 0.23 | .258 | −0.56 | −1.23 | −0.37 |
| Connectives Incidence | 64.50 | 15.08 | 69.42 | 16.35 | 73.00 | 13.91 | .631 | −0.31 | −0.59 | −0.24 |
| LSA Sentence to Sentence | 0.22 | 0.10 | 0.21 | 0.11 | 0.24 | 0.13 | .898 | 0.10 | −0.17 | −0.25 |
| LSA All Sentences | 0.24 | 0.11 | 0.20 | 0.10 | 0.21 | 0.12 | .821 | 0.38 | 0.26 | −0.09 |
| LSA Paragraph to Paragraph | 0.37 | 0.17 | 0.41 | 0.13 | 0.38 | 0.17 | .909 | −0.26 | −0.06 | 0.20 |
Note: Means and SDs of indices reflect values across all passages classified by the SDRT as Purple (P), Brown (Br), or Blue (Bl). Number of Sentences=mean number of sentences in the passage; Number of Words=total number of words in the passage; Words per Sentence=total number of words in the passage divided by total number of sentences in the passage; Syllables per Word=mean number of syllables per content word in the passage; Flesch Reading Ease=readability formula that measures text difficulty based on average words per sentence and average syllables per word in the passage (see Kincaid, Fishburne, Rogers, & Chissom, 1975); Celex Word Frequency=log frequency of content words in the passage (nouns, adverbs, adjectives, main verbs in the passage, see Baayen, Piepenbrock, & van Rijn, 1993); Content Word Concreteness=ratings of word concreteness based on MRC Psycholinguistics Database (Coltheart, 1981), with scores ranging from 100 (abstract) to 700 (concrete); Connective to Verb Ratio=ratio of causal particles to causal verbs in the passage, thus representing causal relationships; Connectives Incidence=incidence of connecting words such as “and, so, then, or, but”; LSA Sentence to Sentence, All Sentences, and Paragraph to Paragraph=semantic overlap based on meaning (see Landauer, McNamara, Dennis, & Kintsch, 2007).