Her persuasion chapter contained main ideas first 50 times and main idea last 2 times. Her expressive writing chapter had main idea first 40 times and last 14 times. In both cases, however, main idea in first position predominates by a wide margin. Because there was no statistical significance for intrabook use of the other position combinations, it appears that the authors of these texts used a fairly consistent pattern in presenting their material. Texts in both composition and sociology have main ideas in the first sentence over 52.0 percent of the time.
Last position occurs with less regularity in writing texts.
Other positions seem unimportant in both fields. Table 3 shows the frequency of all main idea clues in the composition texts. Examples and repetition of important material are universally used with great frequency. If an idea is repeated, or if it is accompanied by one or more examples, it seems to be important. Other clues vary in frequency of usage.