Michael J. Wenger

Comprehension and retention of nonlinear text : Considerations of working memory and material-appropriate processing

The specific processes that support comprehension and retention of hypertext information and the manner in which those processes differ from those involved in the comprehension and retention of traditional linear text were examined in 4 experiments. Experiments 1 and 2 demonstrate that although processing hypertext is not more demanding overall than processing linear text, processing hypertext does make more demands for use of relational information. Experiments 3 and 4 provide tests of the operational assumptions and methods used in the initial two experiments and provide converging evidence to support the notion that hypertext requires a different balance of processing resources than does linear text. Results and directions for research with new information technologies are discussed using the constructs of a limited-capacity working memory and material-appropriate processing.

The relevance of reliability and validity to usability testing

The authors argue that while usability testers have drawn on demonstrated practices from a variety of the social and clinical sciences in developing their methods, they have not concerned themselves with the reliability and validity of the data produced. The authors suggest that the concepts of reliability and validity are relevant to usability testing and that a concern for reliability and validity will enhance the credibility and effectiveness of usability testers. >

Effects of Speech Intelligibility Level on Concurrent Visual Task Performance

Four experiments were performed to determine if changes in the level of speech intelligibility in an auditory task have an impact on performance in concurrent visual tasks. The auditory task used in each experiment was a memory search task in which subjects memorized a set of words and then decided whether authority presented probe items were members of the memorized set. The visual tasks used were an unstable tracking task, a spatial decision-making task, a mathematical reasoning task, and a probability monitoring task. Results showed that performance on the unstable tracking and probability monitoring tasks was unaffected by the level of speech intelligibility on the auditory task, whereas accuracy in the spatial decision-making and mathematical processing tasks was significantly worse at low speech intelligibility levels. The findings are interpreted within the framework of multiple resource theory.

On the rhetorical contract in human-computer interaction

Abstract The social identity of a participant in any form of human communication is in many ways determined and maintained by the patterned use of symbols. Research has illuminated the variety of ways that this is done in the standard forms of communication, such as conversation and text; much less, however, is known about the determination and maintenance of social identity in human—computer interaction. This paper reports an exploration of the rhetorical contract, or the expectation for appropriate interaction, as it develops in human—computer interaction. Subjects used either a direct manipulation or a command interface that, at an unannounced point in the interaction, presented an error message that was either consistent or inconsistent with the interfaces previous pattern of interaction. Results indicated that the direct manipulation interfaces were more likely to establish social expectations and that users of the direct manipulation interface that experienced an incosistent error message expressed large negative affective responses. These results suggest that the social nature of human—computer interactions can be examined with reference to the constructs applicable to other forms of communication.

Reduced Text Structure at Two Text Levels: Impacts on the Performance of Technical Readers.

Cues to text structure have been proposed to operate a number of different levels and it has been suggested that lower-level factors (e.g., word decoding) are more critical to reader performance than are higher-level factors (e.g., paragraph and text structure). The current study involved presenting texts in their base form and with cues to coherence at two levels—at the word and paragraph level—removed. These manipulations were performed on technical texts at two levels of familiarity and were presented to technical readers. Tests of recall, recognition, and problem-solving revealed that while removal of cues to local coherence did produce reliable decrements in reader performance, more dramatic effects occurred when both types of cues were removed. Results are discussed in terms of their relevance to questions of information design.

Selective disruption of hypermnesia for pictures and words

In this study, we investigated the effects of various interpolated tasks on hypermnesia (improved recall across repeated tests) for pictures and words. In five experiments, subjects studied either pictures or words and then completed two free-recall tests, with varying activities interpolated between the tests. The tasks performed between tests were varied to test several hypotheses concerning the possible factor(s) responsible for disruption of the hypermnesic effect. In each experiment, hypermnesia was obtained in a control condition in which there was no interpolated task between tests. The remaining conditions showed that the effect of the interpolated tasks was related to the overlap of the cognitive processes involved in encoding the target items and performing the interpolated tasks. When pictures were used as the target items, no hypermnesia was obtained when subjects engaged in imaginal processing interpolated tasks, even when these tasks involved materials that were very distinct from the target items. When words were used as the target items, no hypermnesia was obtained when the interpolated tasks required verbal/linguistic processing, even when the items used in these tasks were auditorily presented. The results are discussed in terms of a strength-based model of associative memory.

Improving Memory Through Practice

This chapter is concerned with the manner in which practice performing various memory tasks influences subsequent performance. Although memory practice involves learning, simply calling the beneficial effects of memory practice “learning” does little to enhance our understanding of these effects, because the standard definition of learning (i.e., “the relatively permanent change in behavior that results from experience”) provides us with little information regarding (a) the extent to which changes in memory behavior generalize across tasks, (b) the role that the nature of the experience plays in producing the observed changes, and (c) the structure or processes that change as a result of practice. These three issues must be addressed in order to provide a proper theoretical interpretation of practice effects in memory and constitute the focus of the present chapter.

The technical communicator's guide to understanding statistics and research design

Technical communicators are faced daily with digesting the results of research reports; however, many technical communicators do not have the training that would facilitate their comprehension of such reports, particularly the sections of research reports that cite statistical terminology. This article addresses the need of technical communicators to become critical readers of empirical research. Specifically, we present simple definitions of selected research designs and statistical concepts and accompany these definitions with concrete examples related to the field of technical communication research.

Initial recall, reminiscence, and hypermnesia: comment on Madigan and O'Hara (1992).

S. Madigan and R. OHara (1992) analyzed data from repeated free-recall experiments and concluded that the rate of item recovery across tests was related to the level of recall performance on an initial free-recall test. We report a reanalysis of these data along with Monte Carlo simulations that indicate the measures used by Madigan and OHara may have inflated the magnitude of the relation between initial recall and item recovery. The results are discussed in terms of their implications for future research investigating reminiscence and hypermnesia.

Interaction of reader skills and document demands

One strategy for improving the usability of information products is to develop generic descriptions of the products users. Designers can then plan and implement their information products with these generic descriptions in mind. However, designers who develop information based on a generic user type make two associated assumptions, both of which are problematic. First, they assume that differences in reading skills are invariant across texts of differing difficulty and user familiarity. Secondly, they make the logically related assumption that usability is a concern only for readers and users possessing less-developed skills. A study that challenges these assumptions is summarized. Specifically, the authors challenge the assumption that reader performance, particularly the performance of skilled technical readers, is solely a function of reader characteristics. It is possible to manipulate aspects of a text such that skilled readers, when given difficult and/or unfamiliar text, will perform like less-skilled readers in terms of their recall and application of information. It is necessary to consider ease of reading and use in the design of technical information for technical professionals.<<ETX>>