Effects of variable encoding and spaced presentations on vocabulary learning.

] examined the applicability of the encoding variability hypothesis and the spacing phenomenon to vocabulary learning in five experiments. I manipulated encoding variability by varying the number of potential retrieval routes to the word meanings, using a one-sentence context condition, a three-sentence context condition, and a no-context (definitions-only) control condition. I evaluated the spacing effect by presenting each word with or without intervening words. The results provided no evidence that the opportunity to establish multiple retrieval routes by means of contextual information is helpful to vocabulary learning, a conclusion supported unequivocally by all five experiments. By contrast, spaced presentations yielded substantially higher levels of learning than did massed presentations. I discuss the results largely in terms of educational concerns, including the utility of the learning-from-context approach to vocabulary learning. In the experiments reported in this article, 1 investigated the applicability of two principles derived from traditional verbal learning research—variable encoding and the spacing effect—to a real-world activity, vocabulary learning. More specifically, the principal questions under investigation were whether vocabulary learning would be enhanced by (a) the opportunity to establish multiple retrieval routes to word meanings and (b) spaced rather than massed presentations of the to-be-learned information.