The effects of the number of links and navigation support on cognitive load and learning with hypertext: The mediating role of reading order

Problems in learning with hypertext systems have been claimed to be caused by high levels of disorientation and cognitive load. This was recognized by DeStefano and LeFevre [DeStefano, D., & LeFevre, J. -A., (2007). Cognitive load in hypertext reading: A review. Computers in Human Behavior, 23(3), 1616–1641.] who predicted an increase of cognitive load and impairment of learning for hypertexts with a higher number of links per page. From a practical perspective, several navigation support techniques, such as providing link suggestions, have been proposed for guiding learners and reducing cognitive overload. In an experiment, we tested DeStefano and LeFevre’s predictions as well as the usefulness of link suggestions. Participants used different versions of a hypertext, either with 3-links or 8-links per page, presenting link suggestions or not. We tested their cognitive load and learning outcomes. Results showed that there was a benefit of using link suggestions for learning, but no effect of number of links on learning was found. Moreover, the effects of our manipulations on cognitive load were mediated by the reading order that participants selected. Implications for research and the design of navigation support systems are discussed.     

Effect of high-level content organizers on hypertext learning

This study investigates the cognitive abilities involved in hypertext learning and design approaches that can help users. We examined the effects of two types of high-level content organizers - a graphic spatial map and an alphabetical list - on readers’ memory for hypertext structure. In the control condition, a simple “home” page with no navigational aid was offered. Subjects were asked to read the hypertext with the purpose of learning the content, but in the post test phase they also had to recall the layout of nodes and links. Memory for links and page places varied as a function of condition. When a spatial map was available participants reconstructed more accurate formal structure then in the two other conditions. Participants’ memory about page places was the least accurate in the list condition. Results also indicate that participants use the content organizer when it is available in order to orientate during learning from hypertext documents.Our results prove that a content organizer showing the formal structure can facilitate the spatial mapping process. However, an organizer exposing a different structure than the real one would generate a conflict.     

Efficacy of a map on search, orientation and access behaviour in a hypermedia system

Many researchers have proposed hypertext and hypermedia as superior learning environments over traditional linear-based approaches. At the same time, reports of disorientation amongst students working in these environments has become a topic of major concern. The study reported in this paper sets out to investigate the efficacy of the provision of maps on students' ability to search, orientation and access information in a hypertext-based learning task. The domain used required students to learn about the theory of tectonic plates. The results indicate that the greater use of maps led to less relevant searching behaviour and less effective search effort. In conclusion, it is argued that the concept of the spatial metaphor has not served the designers and students of hypertext and hypermedia environments well. Further, it is proposed that designers of non-linear learning environments would be better served by concentrating on the fundamental usability of their systems rather than attempting to introduce navigational aids, which themselves are a symptom of poor design.     

Concepts for improved visualization of Web link attributes

This paper discusses methods to generate and display automatically additional hyperlink information to the users of the World Wide Web. Current Web browsers make it hard to predict what will happen if a link is followed: users get different information than they expect, a new window may be opened, a download starts, or the destination object is just not available. Instead of giving an appropriate notification in advance, users have to follow a link, check whether the document contains the expected information, get back, try another link etc. However, usually it is possible to obtain additional hyperlink information from several sources like link anchor tags, the user's history and Web servers. Furthermore, with little enhancements, Web servers may include even more additional information to the hyperlinks in Web documents. These can be displayed before users select a link to improve navigation and reduce the cognitive overhead. In this paper several types of Web hyperlink information are listed, potential methods to present these facts are compared, the prototype implementation of the proposed concept — called by us HyperScout — is presented, and further developments are discussed.     

Reading skills and children’s navigation strategies in hypertext

Prior research has identified two important navigation strategies that have a clear impact on hypertext comprehension: link selection and overview processing strategies. The first relate to the order in which students select hyperlinks while trying to comprehend a hypertext, whereas the second relate to when and for how long students process navigation overviews, a text device that conveys the text structure by displaying sections, titles and their relations. Most prior research in navigation strategies has been conducted with undergraduate students. We extend prior research by exploring the navigation strategies used by sixth-graders while reading a hypermedia system. We also investigate how reading skills relate to the use of navigation strategies, and how both shape students’ comprehension in hypertext. Results from an electronic reading study replicated in sixth-graders the results on navigation strategies previously found in undergraduate samples. In addition, the results revealed that reading skills predicted the use of link selection but not of overview processing strategies. We discuss our results in light of new models of electronic reading proficiency, and propose some instructional guidelines to improve children’ electronic reading proficiency.     

Cognitive load in hypermedia reading comprehension: Influence of text type and linearity

In this paper the assumption of cognitive overhead in hypermedia learning is specified by cognitive load theory. This analysis is based on different types of cognitive load, the dimension of linearity/non-linearity as well as text characteristics. We propose a model stating that extraneous cognitive load in hypermedia learning is basically determined by the interaction of text presentation format (linear/non-linear) with text type (text with and without narrative structures). This assumption was tested by means of a 2 × 2 experimental design. Sixty participants completed a computer-based learning program that contained a narrative text or an encyclopaedia text in either linear or non-linear presentation format. Results confirm the suggested interaction hypothesis postulating that non-linear information presentation of narrative text structure increases cognitive load and decreases knowledge acquisition. However, for encyclopaedia text participants’ knowledge acquisition was not affected by linear or non-linear presentation format. Furthermore, results suggest a cross-validation of cognitive load measures and propositional analysis.     

The effect of visual design and placement of intra-article navigation schemes on reading comprehension and website user perceptions

Multipage articles on websites require intra-article navigation schemes and, when well designed, such navigational schemes signal the topical structure of the article’s contents. This study examines the effect of the visual design and placement of intra-article navigation schemes on website users’ reading comprehension and user experience. Using an informational medical website, four treatments of an intra-article navigation scheme were varied in their level of visual distinctness from the site’s other navigation devices and in their placement in the web page. Significant differences were found for reading comprehension and perceived knowledge gained. Reading comprehension was highest with an intra-article navigation scheme that was most visually distinct as an article table of contents and that replaced the site’s navigation on the web page layout. Paradoxically, participants’ perceptions of the amount of knowledge they gained were rated lowest for this condition. Suggestions for navigation design are presented.     

一种基于向量空间模型的文本分类方法

介绍的文本分类是指在给定分类体系下,根据文本的内容自动确定文本类别的过程。通过分析网页的特点及因特网用户感兴趣的查询信息,提出了一种基于机器学习的、独立于语种的文本分类模型。这一模型的关键算法主要利用字间的相关信息、词频、页面的标记信息以及对用户的查询信息的浅层语义分析,提取网页特征,并计算可调的词频加权参数和增加特征词的可分性信息,然后通过本类和非本类训练,建立预定义类的特征向量空间,进一步对文本进行分类。这种分类方法在相似文本分类中具有明显的优势。     

Evaluation of hypertext in an activity learning environment

Abstract This paper presents a study which evaluates the use and efficiency of two computer learning tools for basic virology. The first, VIROLAB, is a simulation of a biology laboratory in which the learner uses virtual lab facilities to help defective viruses to multiply. The system also includes a hypertext that provides learners with some knowledge on virology. The second tool is the hypertext which has been extracted from VIROLAB and which is now considered as an independent learning environment. This study addressed two specific questions: (1) which of the two tools was the most efficient for knowledge acquisition, and (2) were there any differences in the use of the two hypertexts? Comparison of pre‐ and post‐test scores showed that neither of the two learning tools is better than the other. However, analysis of the navigation paths showed that VIROLAB users dissociated the reading of the integrated hypertext from the problem resolution activities. The implications of this finding for the design of the learning environment are discussed.     

Natural language understanding within a cognitive semantics framework

The article argues that cognitive linguistic theory may prove an alternative to the Montague paradigm for designing natural language understanding systems. Within this framework it describes a system which models language understanding as a dialogical process between user and computer. The system operates with natural language texts as input and represent language meaning as entity-relationship diagrams.     

Web-based learning programs: Use by learners with various cognitive styles

To consider how Web-based learning program is utilized by learners with different cognitive styles, this study presents a Web-based learning system (WBLS) and analyzes learners’ browsing data recorded in the log file to identify how learners’ cognitive styles and learning behavior are related. In order to develop an adapted WBLS, this study also proposes a design model for system designers to tailor the preferences linked with each cognitive style. The samples comprise 105 third-grade Accounting Information System course students from a technology university in central Taiwan. Analytical results demonstrate that learners with different cognitive styles have similar but linear learning approaches, and learners with different cognitive styles adopt different navigation tools to process learning.     

一种基于超文本标签修改和附加字符实现信息隐藏的方法

分析HTML文档的结构和特点,对当前基于超文本实现信息隐藏所采用的技术进行了分析,提出一种对超文本文档修改较少且不影响页面显示效果,同时可以实现较大信息量隐藏的新方法.经试验证明,该方法具有较好的不可见性和较高的安全性.     

Ontological semantic inference based on cognitive map

Cognitive map is a well-known approach to model the dynamics of qualitative systems, and has been studied and used in various fields, such as psychology, education, engineering, and management. Although the validity and usefulness of cognitive maps has been proven in many fields, and a considerable number of cognitive maps have been built during the last decade, cognitive map construction and use was just one-off event. In addition, the high degree of cognitive complexities in large cognitive maps makes it difficult for others to understand and exploit the pre-defined cognitive map in another similar domain problem.In this paper, an ontological semantic inference method, which combines the cognitive map and semantic influence, is proposed. This approach reuses a pre-defined cognitive map and provides an ontological semantic inference mechanism in decision making environments by reducing the degree of cognitive complexities in a large cognitive map.     

车辆定位与导航系统中的数字地图

数字地图是车辆定位与导航系统中的重要组成部分,数字地图的设计直接关系到整个系统的成败。本文首先进行需求分析,然后探讨了数字地图的内容、结构及其面向对象的实现。     

Incorporating self-organizing map with text mining techniques for text hierarchy generation

Self-organizing maps (SOM) have been applied on numerous data clustering and visualization tasks and received much attention on their success. One major shortage of classical SOM learning algorithm is the necessity of predefined map topology. Furthermore, hierarchical relationships among data are also difficult to be found. Several approaches have been devised to conquer these deficiencies. In this work, we propose a novel SOM learning algorithm which incorporates several text mining techniques in expanding the map both laterally and hierarchically. On training a set of text documents, the proposed algorithm will first cluster them using classical SOM algorithm. We then identify the topics of each cluster. These topics are then used to evaluate the criteria on expanding the map. The major characteristic of the proposed approach is to combine the learning process with text mining process and makes it suitable for automatic organization of text documents. We applied the algorithm on the Reuters-21578 dataset in text clustering and categorization tasks. Our method outperforms two comparing models in hierarchy quality according to users’ evaluation. It also receives better F1-scores than two other models in text categorization task.