Kenneth L. Leicht

The Effects of Imaginal and Verbal Strategies on Prose Comprehension by Adults.

Adult subjects were given concrete and abstract textbook passages to study by using either an imaginai or verbal strategy. Two days later, they were given a multiple-choice test and a production test of comprehension. The verbal strategy produced better comprehension than the imaginai strategy; concrete passages were comprehended better than abstract passages, but only according to the production test; and strategy and concreteness did not interact. Differences between these results and results obtained in imagery research on word lists are discussed, and caution is advised before generalizing the word research to meaningful prose learning by adults

Differential rehearsal and primacy effects

Rehearsal of initial list items at the expense of middle list items was hypothesized to account for primacy effects in a free-recall (FR) task. Three predictions from the hypothesis were: (a) Primacy effects should be reduced under instructions not to rehearse prior list items; (b) the size of the primacy effect should increase with increasing presentation duration of list items; (c) the increase in the magnitude of the primacy effect with increasing presentation duration should be greater under conventional than under nonrehearsal FR instructions. Only prediction (b) was supported. Nonconfirmation of remaining predictions may have been due to S s inability to avoid rehearsal of prior list items under nonrehearsal instructions.

Type of Highlighted Material and Examination Performance

AbstractThe present study asks whether laboratory findings, that isolation of an item facilitates its recall, extend to formal educational settings. Four groups of students from a General Psychology class were differentiated in terms of the type of material which was isolated in assigned readings. Principles, examples of principles, or trivial statements were selected for isolation by underlining; readings of the remaining group did not contain underlinings. Class examinations included questions directed at knowledge of each type of material. Slight support was obtained for the prediction that exam performance on a particular type of material depended upon whether the material was isolated. There was no evidence for an overall facilitation by isolation. That is, underlining of one type of material did not appear to aid exam performance on non-isolated materials.

USE OF ANALYSIS OF VARIANCE TO ASSESS INDIVIDUAL DIFFERENCES IN LEARNING

Historically statistical tests of significance have not permitted determination of whether the trials effect (learning) differs reliably across learners. A common statistical test, analysis of variance, can ordinarily only be used to assess whether the trials effect varies across experimental treatments. However, the learning situation can be so rearranged that reliable individual differences in learning can be statistically evaluated. The proposed arrangement is such that learning materials, rather than learner, is the randomization unit. An illustration of the use of analysis of variance to evaluate individual differences in learning, when the learning setting is rearranged, is given.

Effects of Temporal Sequencing of Student Study and Teacher Presentation on Examination Performance

Whether students should read class materials prior to or after teacher presentation was investigated. One hundred twenty-eight General Psychology students were assigned to the two conditions, 64 per condition. Students in the prior-reading condition read two reprints, 10 minutes per reprint. The post-reading group was then assembled with the prior-reading group for a teacher presentation of reprint materials. Following teacher presentation, the post-reading group was retained and read the reprints. One day later both groups were given multiple-choice tests on the reprints. No difference in test performance was found for the two groups.

Effects of meaningfulness on the isolation effect

Two assumptions pertinent to isolation-effect studies were examined. Contrary to an assumption that the isolation effect is due to differential rehearsal of conspicuous items, instructions designed to distribute practice time across list items did not reduce the isolation effect. Prediction of equivalent total list recall for isolation and nonisolation conditions followed from an assumption that isolating a list item alters the distribution but not total amount of list rehearsal. Contrary to the latter assumption, total list recall was lower in isolation than in nonisolation conditions, except under instructions to distribute rehearsal time and with low-meaningful units.

Effect of number and relatedness of stimulus-term components on paired-associate learning

Word compounds comprised of two or three conceptually related or two or three unrelated words formed the stimulus terms in four paired-associate (PA) lists. List learning was more rapid when stimuli were compounds of conceptually related words than when stimuli consisted of unrelated words. An effect of number of words in the compounds and the interaction of number and relatedness of compound words were not obtained. Results were interpreted in terms of stimulus selection.

Some Remarks on the Expected Mean Squares in Analysis of Variance in the Assessment of Individual Differences in Learning

Leicht, et al. (1978) proposed that learning units, e.g., lists, passages, be randomization units, rather than learners (subjects) as is typical, so that the significance of trial-learner interactions can be tested with analysis of variance. In an illustrative application of the suggested rearrangement, learners were arbitrarily selected (fixed-effects factor). If the investigator wishes greater generalizability of individual differences in learning, learners must be randomly selected from a specified population (random-effects factor). The appropriate expected mean squares and tests of significance are presented for both models and subsequent comments are made.