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The consistent finding that internationally coauthored papers are more heavily cited has led to a tacit agreement among politicians and scientists that international collaboration in scientific research should be particularly promoted. However, existing studies of research collaboration suffer from a major weakness in that the Thomson Reuters Web of Science until recently did not link author names with affiliation addresses. The general approach has been to hierarchically code papers into international paper, national paper, or local paper based on the address information. This hierarchical coding scheme severely understates the level and contribution of local or national collaboration on an internationally coauthored paper. In this research, I code collaboration variables by hand checking each paper in the sample, use two measures of a paper's impact, and try several regression models. I find that both international collaboration and local collaboration are positively and significantly associated with a paper's impact, but international collaboration does not have more epistemic authority than local collaboration. This result suggests that previous findings based on hierarchical coding might be misleading. [ABSTRACT FROM AUTHOR]

With more and more information available on the Internet, the task of making personalized recommendations to assist the user's navigation has become increasingly important. Considering there might be millions of users with different backgrounds accessing a Web site everyday, it is infeasible to build a separate recommendation system for each user. To address this problem, clustering techniques can first be employed to discover user groups. Then, user navigation patterns for each group can be discovered, to allow the adaptation of a Web site to the interest of each individual group. In this paper, we propose to model user access sequences as stochastic processes, and a mixture of Markov models based approach is taken to cluster users and to capture the sequential relationships inherent in user access histories. Several important issues that arise in constructing the Markov models are also addressed. The first issue lies in the complexity of the mixture of Markov models. To improve the efficiency of building/maintaining the mixture of Markov models, we develop a lightweight adapt-ive algorithm to update the model parameters without recomputing model parameters from scratch. The second issue concerns the proper selection of training data for building the mixture of Markov models. We investigate two different training data selection strategies and perform extensive experiments to compare their effectiveness on a real dataset that is generated by a Web-based knowledge management system, Livelink. [ABSTRACT FROM AUTHOR]

In this paper, we present a framework for clustering Web search engine queries whose aim is to identify groups of queries used to search for similar information on the Web. The framework is based on a novel term vector model of queries that integrates user selections and the content of selected documents extracted from the logs of a search engine. The query representation obtained allows us to treat query clustering similarly to standard document clustering. We study the application of the clustering framework to two problems: relevance ranking boosting and query recommendation. Finally, we evaluate with experiments the effectiveness of our approach. [ABSTRACT FROM AUTHOR]

Co-occurrence matrices, such as cocitation, coword, and colink matrices, have been used widely in the information sciences. However, confusion and controversy have hindered the proper statistical analysis of these data. The underlying problem, in our opinion, involved understanding the nature of various types of matrices. This article discusses the difference between a symmetrical cocitation matrix and an asymmetrical citation matrix as well as the appropriate statistical techniques that can be applied to each of these matrices, respectively. Similarity measures (such as the Pearson correlation coefficient or the cosine) should not be applied to the symmetrical cocitation matrix but can be applied to the asymmetrical citation matrix to derive the proximity matrix. The argument is illustrated with examples. The study then extends the application of co-occurrence matrices to the Web environment, in which the nature of the available data and thus data collection methods are different from those of traditional databases such as the Science Citation Index. A set of data collected with the Google Scholar search engine is analyzed by using both the traditional methods of multivariate analysis and the new visualization software Pajek, which is based on social network analysis and graph theory. [ABSTRACT FROM AUTHOR]

Web citations have been proposed as comparable to, even replacements for, bibliographic citations, notably in assessing the academic impact of work in promotion and tenure decisions. We compared bibliographic and Web citations to articles in 46 journals in library and information science. For most journals (57%), Web citations correlated significantly with both bibliographic citations listed in the Social Sciences Citation Index and the ISI's Journal Impact Factor. Many of the Web citations represented intellectual impact, coming from other papers posted on the Web (30%) or from class readings lists (12%). Web citation counts were typically higher than bibliographic citation counts for the same article. Journals with more Web citations tended to have Web sites that provided tables of contents on the Web, while less cited journals did not have such publicity. The number of Web citations to journal articles increased from 1992 to 1997. [ABSTRACT FROM AUTHOR]

Network structure analysis plays an important role in characterizing complex systems. Different from previous network centrality measures, this article proposes the topological centrality measure reflecting the topological positions of nodes and edges as well as influence between nodes and edges in general network. Experiments on different networks show distinguished features of the topological centrality by comparing with the degree centrality, closeness centrality, betweenness centrality, information centrality, and PageRank. The topological centrality measure is then applied to discover communities and to construct the backbone network. Its characteristics and significance is further shown in e-Science applications. [ABSTRACT FROM AUTHOR]

In recent years, many evaluations of Web sites have been conducted, and relevant researches have also been carried out in academic circles. Correspondence analysis is introduced in this paper to evaluate university library Web sites through building a correspondence analysis model. This paper gives suggestions as to how to construct university library Web sites based on analysis and summary of evaluation results, in a bid to strengthen the construction of university library Web sites. [ABSTRACT FROM AUTHOR]

Flickr, the large-scale online photo sharing website, is often viewed as one of the 'classic' examples of Web2.0 applications through which researchers are able to observe the social behavior of online communities. One of the main features of Flickr is groups. These provide a means to organize, share and discuss photos of potential interest to group members. This paper explores the scale of group creation on Flickr and proposes a new set of metrics for characterizing groups on Flickr looking at aspects of membership, communication activity, and communication structure. Data collected from a sample of 1,000 groups was used to confirm the metrics and provide new insights into group formation in Flickr, such as the nature of larger and smaller groups. The contributions of the article are as follows: a set of metrics for characterizing online groups that extend existing schemes; an approach for sampling Flickr to estimate the number of groups; new insights into Flickr groups based on results from analyzing 1,000 randomly selected groups; and reflections on our experiences with using publicly accessible, automatically collected data to characterize the types of groups on Flickr. [ABSTRACT FROM AUTHOR]

Wikis are designed to support collaborative editing, without focusing on individual contribution, such that it is not straightforward to determine who contributed to a specific page. However, as wikis are increasingly adopted in settings such as business, government, and education, where editors are largely driven by career goals, there is a perceived need to modify wikis so that each editor's contributions are clearly presented. In this paper we introduce an approach for assessing the contributions of wiki editors along several authorship categories, as well as a variety of information glyphs for visualizing this information. We report on three types of analysis: (a) assessing the accuracy of the algorithms, (b) estimating the understandability of the visualizations, and (c) exploring wiki editors' perceptions regarding the extent to which such an approach is likely to change their behavior. Our findings demonstrate that our proposed automated techniques can estimate fairly accurately the quantity of editors' contributions across various authorship categories, and that the visualizations we introduced can clearly convey this information to users. Moreover, our user study suggests that such tools are likely to change wiki editors' behavior. We discuss both the potential benefits and risks associated with solutions for estimating and visualizing wiki contributions. [ABSTRACT FROM AUTHOR]

Weblogs are gaining momentum as one of most versatile tools for online scholarly communication. Since academic weblogs tend to be used by scholars to position themselves in a disciplinary blogging community, links are essential to their construction. The aim of this article is to analyze the reasons for linking in academic weblogs and to determine how links are used for distribution of information, collaborative construction of knowledge, and construction of the blog's and the blogger's identity. For this purpose I analyzed types of links in 15 academic blogs, considering both sidebar links and in-post links. The results show that links are strategically used by academic bloggers for several purposes, among others to seek their place in a disciplinary community, to engage in hypertext conversations for collaborative construction of knowledge, to organize information in the blog, to publicize their research, to enhance the blog's visibility, and to optimize blog entries and the blog itself. [ABSTRACT FROM AUTHOR]

A common problem in the spatialization of information systems is the determination of geometry; i.e., dimensionality and metric. Such geometry is either chosen a priori or is inferred a posteriori from secondary data. Recent work emphasizes the use of geometric information latent in a system's navigational record. Resolving this information from its noisy background, however, requires an unambiguous criterion of selection. In this paper we use a previously published, statistical method for resolving a Web-based information system's geometry from navigational data. However, because of the method's (theoretical) sensitivity to data selection, a weighted frequency correction based on empirical probability distributions is applied. The effect of this correction on the Web-space geometry is investigated. Results indicate that the inferred geometry is robust; i.e., it does not significantly change under this probabilistic correction. [ABSTRACT FROM AUTHOR]

Modern Standard Arabic (MSA) is the official language used in all Arabic countries. In this paper we describe an investigation of the uniformity of MSA across different countries. Many studies have been carried out locally or regionally on Arabic and its dialects. Here we look on a more global scale by studying language variations between countries. The source material used in this investigation was derived from national newspapers available on the Web, which provided samples of common media usage in each country. This corpus has been used to investigate the lexical characteristics of Modem Standard Arabic as found in 10 different Arabic speaking countries. We describe our collection methods, the types of lexical analysis performed, and the results of our investigations. With respect to newspaper articles, MSA seems to be very uniform across all the countries included in the study, but we have detected various types of differences, with implications for computational processing of MSA. [ABSTRACT FROM AUTHOR]

Web links have been studied by information scientists for at least six years but it is only in the past two that clear evidence has emerged to show that counts of links to scholarly Web spaces (universities and departments) can correlate significantly with research measures, giving some credence to their use for the investigation of scholarly communication. This paper reports on a study to investigate the factors that influence the creation of links to journal Web sites. An empirical approach is used: collecting data and testing for significant patterns. The specific questions addressed are whether site age and site content are inducers of links to a journal's Web site as measured by the ratio of link counts to Journal Impact Factors, two variables previously discovered to be related. A new methodology for data collection is also introduced that uses the Internet Archive to obtain an earliest known creation date for Web sites. The results show that both site age and site content are significant factors for the disciplines studied: library and information science, and law. Comparisons between the two fields also show disciplinary differences in Web site characteristics. Scholars and publishers should be particularly aware that richer content on a journal's Web site tends to generate links and thus the traffic to the site. [ABSTRACT FROM AUTHOR]

The Web, during its 15 years of existence, has become a major information and communication medium. It is well known that the Web is growing at an enormous rate, due to its popularity and prevalence. Different aspects of the growth of the Web have been extensively studied and discussed. However, relatively little has been said about additional processes that take place on the Web. The Web is evolving constantly, but growth is not the only process that influences it. Web page modification and disappearance of the specific page or of the server on which the page resided and resurfacing sometimes at a different URL also have important roles in shaping the Web. As the rate of growth slows down-according to the OCLC report this has already started to take place-these additional processes will become more and more emphasized. This article analyzes the changes that occurred to a set of Web pages related to informetrics during a period of five years between June 1998 and June 2003. The Web pages were collected and monitored four times, in June 1998, 1999, 2002, and 2003. The results indicate that modification, disappearance and resurfacing cannot be ignored when studying the structure and development of the Web.

Presents results from published studies of Web searching to determine the current state of research. Indication of divergent research methods and terminology; Proposed framework for future studies that will facilitate comparison of results; Searching characteristics of Web users.

The amount of information on the Web has been expanding at an enormous pace. There are a variety of Web documents in different genres, such as news, reports, reviews. Traditionally, the information displayed on Web sites has been static. Recently, there are many Web sites offering content that is dynamically generated and frequently updated. It is also common for Web sites to contain information in different languages since many countries adopt more than one language. Moreover, content may exist in multimedia formats including text, images, video, and audio. [ABSTRACT FROM AUTHOR]

A huge number of informal messages are posted every day in social network sites, blogs, and discussion forums. Emotions seem to be frequently important in these texts for expressing friendship, showing social support or as part of online arguments. Algorithms to identify sentiment and sentiment strength are needed to help understand the role of emotion in this informal communication and also to identify inappropriate or anomalous affective utterances, potentially associated with threatening behavior to the self or others. Nevertheless, existing sentiment detection algorithms tend to be commercially oriented, designed to identify opinions about products rather than user behaviors. This article partly fills this gap with a new algorithm, SentiStrength, to extract sentiment strength from informal English text, using new methods to exploit the de facto grammars and spelling styles of cyberspace. Applied to MySpace comments and with a lookup table of term sentiment strengths optimized by machine learning, SentiStrength is able to predict positive emotion with 60.6% accuracy and negative emotion with 72.8% accuracy, both based upon strength scales of 1-5. The former, but not the latter, is better than baseline and a wide range of general machine learning approaches. [ABSTRACT FROM AUTHOR]

This study explored the feasibility of using Web hyperlink data to study European political Web sites. Ninety-six European Union (EU) political parties belonging to a wide range of ideological, historical, and linguistic backgrounds were included in the study. Various types of data on Web links to party Web sites were collected. The Web colink data were visualized using multidimensional scaling (MDS), while the inlink data were analyzed with a 2-way analysis of variance test. The results showed that Web hyperlink data did reflect some political patterns in the EU. The MDS maps showed clusters of political parties along ideological, historical, linguistic, and social lines. Statistical analysis based on inlink counts further confirmed that there was a significant difference along the line of the political history of a country, such that left-wing parties in the former communist countries received considerably fewer inlinks to their Web sites than left-wing parties in countries without a history of communism did. The study demonstrated the possibility of using Web hyperlink data to gain insights into political situations in the EU. This suggests the richness of Web hyperlink data and its potential in studying social-political phenomena. [ABSTRACT FROM AUTHOR]

This study investigated factors that motivate or impede faculty participation in self-archiving practices—the placement of research work in various open access (OA) venues, ranging from personal Web pages to OA archives. The author's research design involves triangulation of survey and interview data from 17 Carnegie doctorate universities with DSpace institutional repositories. The analysis of survey responses from 684 professors and 41 telephone interviews identified seven significant factors: (a) altruism—the idea of providing OA benefits for users; (b) perceived self-archiving culture; (c) copyright concerns; (d) technical skills; (e) age; (f) perception of no harmful impact of self-archiving on tenure and promotion; and (g) concerns about additional time and effort. The factors are listed in descending order of their effect size. Age, copyright concerns, and additional time and effort are negatively associated with self-archiving, whereas remaining factors are positively related to it. Faculty are motivated by OA advantages to users, disciplinary norms, and no negative influence on academic reward. However, barriers to self-archiving—concerns about copyright, extra time and effort, technical ability, and age—imply that the provision of services to assist faculty with copyright management, and with technical and logistical issues, could encourage higher rates of self-archiving. [ABSTRACT FROM AUTHOR]

Politicians' Web sites have been considered a medium for organizing, mobilizing, and agenda-setting, but extant literature lacks a systematic approach to interpret the Web sites of senators—a new medium for political communication. This study classifies the role of political Web sites into relational (hyperlinking) and topical (shared-issues) aspects. The two aspects may be viewed from a social embeddedness perspective and three facets, as K. Foot and S. Schneider (2002) suggested. This study employed network analysis, a set of research procedures for identifying structures in social systems, as the basis of the relations among the system's components rather than the attributes of individuals. Hyperlink and issue data were gathered from the United States Senate Web site and Yahoo. Major findings include: (a) The hyperlinks are more targeted at Democratic senators than at Republicans and are a means of communication for senators and users; (b) the issue network found from the Web is used for discussing public agendas and is more highly utilized by Republican senators; (c) the hyperlink and issue networks are correlated; and (d) social relationships and issue ecologies can be effectively detected by these two networks. The need for further research is addressed. [ABSTRACT FROM AUTHOR]

The study examined the possibility of constructing business profiles (specifically, product profiles) based on keyword patterns on various types of Web sites, including a company's own Web site, blog sites, and Web sites that have particular keywords and also hyperlinks pointing to company Web sites. To test the proposed methods, we selected China's four major oil companies and two other companies that have related products. We collected three rounds of data over a 7-month period from these three Web sources and analyzed the numbers of retrieved pages to construct business profiles. The business profiles constructed were checked against business information collected from other sources such as company annual reports and company newsletters to determine the correctness of the profiles and thus the usefulness of the proposed methods. We found that we can construct fairly accurate profiles by examining the frequency distribution of product keywords on company Web sites. Analyzing the frequency distribution of blogs on various topics was very useful in following major business events and developments during particular time periods. We also conducted qualitative content analysis for a sample of 454 Web pages retrieved from the three sources. Findings from the content analysis confirmed the conclusions from the quantitative analysis. [ABSTRACT FROM AUTHOR]

Despite the development of huge healthcare Web sites and powerful search engines, many searchers end their searches prematurely with incomplete information. Recent studies suggest that users often retrieve incomplete information because of the complex scatter of relevant facts about a topic across Web pages. However, little is understood about regularities underlying such information scatter. To probe regularities within the scatter of facts across Web pages, this article presents the results of two analyses: (a) a cluster analysis of Web pages that reveals the existence of three page clusters that vary in information density and (b) a content analysis that suggests the role each of the above-mentioned page clusters play in providing comprehensive information. These results provide implications for the design of Web sites, search tools, and training to help users find comprehensive information about a topic and for a hypothesis describing the underlying mechanisms causing the scatter. We conclude by briefly discussing how the analysis of information scatter, at the granularity of facts, complements existing theories of information-seeking behavior. [ABSTRACT FROM AUTHOR]

This study evaluates how well the authors of Wikipedia history articles adhere to the site's policy of assuring verifiability through citations. It does so by examining the references and citations of a subset of country histories. The findings paint a dismal picture. Not only are many claims not verified through citations, those that are suffer from the choice of references used. Many of these are from only a few US government Websites or news media and few are to academic journal material. Given these results, one response would be to declare Wikipedia unsuitable for serious reference work. But another option emerges when we jettison technological determinism and look at Wikipedia as a product of a wider social context. Key to this context is a world in which information is bottled up as commodities requiring payment for access. Equally important is the problematic assumption that texts are undifferentiated bearers of knowledge. Those involved in instructional programs can draw attention to the social nature of texts to counter these assumptions and by so doing create an awareness for a new generation of Wikipedians and Wikipedia users of the need to evaluate texts (and hence citations) in light of the social context of their production and use. [ABSTRACT FROM AUTHOR]

Terrorist groups use the Web as their infrastructure for various purposes. One example is the forming of new local cells that may later become active and perform acts of terror. The Advanced Terrorist Detection System (ATDS), is aimed at tracking down online access to abnormal content, which may include terrorist-generated sites, by analyzing the content of information accessed by the Web users. ATDS operates in two modes: the training mode and the detection mode. In the training mode, ATDS determines the typical interests of a prespecified group of users by processing the Web pages accessed by these users over time. In the detection mode, ATDS performs real-time monitoring of the Web traffic generated by the monitored group, analyzes the content of the accessed Web pages, and issues an alarm if the accessed information is not within the typical interests of that group and similar to the terrorist interests. An experimental version of ATDS was implemented and evaluated in a local network environment. The results suggest that when optimally tuned the system can reach high detection rates of up to 100% in case of continuous access to a series of terrorist Web pages. [ABSTRACT FROM AUTHOR]

Though practitioners have seen discussions and debates surrounding the “Web 2.0” concept for the last few years, we know little of Web users' heterogeneity in the usage of Web 2.0 applications, let alone the factors associated with such heterogeneity. In this article, we propose a Web user's degree of Web 2.0-ness to be measured by the weighted average of the degrees of Web 2.0-ness of the Web sites that he or she has visited. A Web site's degree of Web 2.0-ness in turn is evaluated through a series of binary criteria as to whether the site accommodates popular Web 2.0 applications. Utilizing clickstream data from an online panel coupled with expert scoring for the empirical analysis, we find that a Web user's degree of Web 2.0-ness is positively associated with his or her behavioral volume (measured by the number of page views), behavioral speed (measured by the duration of each page view), and behavioral concentration (measured by the Gini coefficient of page views the user made across Web sites). Furthermore, Web users who are younger and male are found to have a higher degree of Web 2.0-ness. [ABSTRACT FROM AUTHOR]

With the increasing number of digital documents, the ability to automatically classify those documents both efficiently and accurately is becoming more critical and difficult. One of the major problems in text classification is the high dimensionality of feature space. We present the ambiguity measure (AM) feature-selection algorithm, which selects the most unambiguous features from the feature set. Unambiguous features are those features whose presence in a document indicate a strong degree of confidence that a document belongs to only one specific category. We apply AM feature selection on a naïve Bayes text classifier. We favorably show the effectiveness of our approach in outperforming eight existing feature-selection methods, using five benchmark datasets with a statistical significance of at least 95% confidence. The support vector machine (SVM) text classifier is shown to perform consistently better than the naïve Bayes text classifier. The drawback, however, is the time complexity in training a model. We further explore the effect of using the AM feature-selection method on an SVM text classifier. Our results indicate that the training time for the SVM algorithm can be reduced by more than 50%, while still improving the accuracy of the text classifier. We favorably show the effectiveness of our approach by demonstrating that it statistically significantly (99% confidence) outperforms eight existing feature-selection methods using four standard benchmark datasets. [ABSTRACT FROM AUTHOR]

Social network sites like MySpace are increasingly important environments for expressing and maintaining interpersonal connections, but does online communication exacerbate or ameliorate the known tendency for offline friendships to form between similar people (homophily)? This article reports an exploratory study of the similarity between the reported attributes of pairs of active MySpace Friends based upon a systematic sample of 2,567 members joining on June 18, 2007 and Friends who commented on their profile. The results showed no evidence of gender homophily but significant evidence of homophily for ethnicity, religion, age, country, marital status, attitude towards children, sexual orientation, and reason for joining MySpace. There were also some imbalances: women and the young were disproportionately commenters, and commenters tended to have more Friends than commentees. Overall, it seems that although traditional sources of homophily are thriving in MySpace networks of active public connections, gender homophily has completely disappeared. Finally, the method used has wide potential for investigating and partially tracking homophily in society, providing early warning of socially divisive trends. [ABSTRACT FROM AUTHOR]

Since millions seek health information online, it is vital for this information to be comprehensible. Most studies use readability formulas, which ignore vocabulary, and conclude that online health information is too difficult. We developed a vocabularly-based, naïve Bayes classifier to distinguish between three difficulty levels in text. It proved 98% accurate in a 250-document evaluation. We compared our classifier with readability formulas for 90 new documents with different origins and asked representative human evaluators, an expert and a consumer, to judge each document. Average readability grade levels for educational and commercial pages was 10th grade or higher, too difficult according to current literature. In contrast, the classifier showed that 70–90% of these pages were written at an intermediate, appropriate level indicating that vocabulary usage is frequently appropriate in text considered too difficult by readability formula evaluations. The expert considered the pages more difficult for a consumer than the consumer did. [ABSTRACT FROM AUTHOR]

This research explores the use of genre as a document descriptor in order to improve the effectiveness of Web searching. A major issue to be resolved is the identification of what document categories should be used as genres. As genre is a kind of folk typology, document categories must enjoy widespread recognition by their intended user groups in order to qualify as genres. Three user studies were conducted to develop a genre palette and show that it is recognizable to users. (Palette is a term used to denote a classification, attributable to Karlgren, Bretan, Dewe, Hallberg, and Wolkert, 1998.) To simplify the users' classification task, it was decided to focus on Web pages from the edu domain. The first study was a survey of user terminology for Web pages. Three participants separated 100 Web page printouts into stacks according to genre, assigning names and definitions to each genre. The second study aimed to refine the resulting set of 48 (often conceptually and lexically similar) genre names and definitions into a smaller palette of user-preferred terminology. Ten participants classified the same 100 Web pages. A set of five principles for creating a genre palette from individuals' sortings was developed, and the list of 48 was trimmed to 18 genres. The third study aimed to show that users would agree on the genres of Web pages when choosing from the genre palette. In an online experiment in which 257 participants categorized a new set of 55 pages using the 18 genres, on average, over 70% agreed on the genre of each page. Suggestions for improving the genre palette and future directions for the work are discussed. [ABSTRACT FROM AUTHOR]

Using an enriched author cocitation analysis (ACA), we map information science (IS) for 1996–2005, a decade of explosive development of the World Wide Web, to examine its development since the landmark study by White and McCain (1998). The Web, we find, has had a profound impact on IS, driving the creation of new disciplines and revitalization or obsolescence of old, and most importantly, bridging the chasm between the “literatures” and “retrieval” IS camps. Simultaneously, the development of IS towards cognitive aspects has intensified. Our study enriches classic ACA in that it employs both orthogonal and oblique rotations in the factor analysis (FA), and reports both pattern and structure matrices for the latter, thus enabling a comparison between these several FA methods in ACA. Each method provides interesting information not available from the others, we find, especially when results are also visualized in the novel manner we introduce here. [ABSTRACT FROM AUTHOR]

The purpose of this article is to critically deconstruct the term engagement as it applies to peoples' experiences with technology. Through an extensive, critical multidisciplinary literature review and exploratory study of users of Web searching, online shopping, Webcasting, and gaming applications, we conceptually and operationally defined engagement. Building on past research, we conducted semistructured interviews with the users of four applications to explore their perception of being engaged with the technology. Results indicate that engagement is a process comprised of four distinct stages: point of engagement, period of sustained engagement, disengagement, and reengagement. Furthermore, the process is characterized by attributes of engagement that pertain to the user, the system, and user-system interaction. We also found evidence of the factors that contribute to nonengagement. Emerging from this research is a definition of engagement—a term not defined consistently in past work—as a quality of user experience characterized by attributes of challenge, positive affect, endurability, aesthetic and sensory appeal, attention, feedback, variety/novelty, interactivity, and perceived user control. This exploratory work provides the foundation for future work to test the conceptual model in various application areas, and to develop methods to measure engaging user experiences. [ABSTRACT FROM AUTHOR]

Personal Web portfolios have become a popular information source and an effective method for individuals to present themselves to others in cyberspace. Thus, the quality of personal Web portfolios is critical and affects the perception that others have of the individuals. But how do we measure quality of personal Web portfolios? What are the important factors affecting quality of personal Web portfolios? This study presents the development of an instrument measuring factors affecting information quality of personal Web portfolios. The proposed instrument, based on the Information Quality framework, was refined and validated to assess its construct validity, convergent validity, and discriminant validity. The proposed instrument can be used to guide those who want to design their personal Web portfolios and also to help those who need to evaluate the quality of personal Web portfolios. [ABSTRACT FROM AUTHOR]

Although the body of literature pertaining to the study of micro, context-specific behavior on the Web is growing, there lacks a global, macro analysis as to the behavioral dimensions of Web users' online activities. In an attempt to fill in the gap, this study proposes a three-dimensional, cubic typology for the characterization of Web users' online information behavior. We discuss a set of hypotheses concerning the relationships among these dimensions as well as those between these dimensions and related behavioral aspects. Online panel data consisting of month-long clickstreams of 2,022 Web users obtained from InsightXplore, Taiwan are made available for the empirical validation of the hypotheses. We found that a Web user's width (i.e., number of categories of Web sites explored), length (i.e., number of sites visited per category), and depth (i.e., number of pages downloaded per site) of online information behavior are highly correlated. Furthermore, these three dimensions of the behavioral “cube” are positively associated with speed of navigation, but negatively associated with the Web users' explicit online information search propensity and the degree of relatedness among the sites they visited. [ABSTRACT FROM AUTHOR]

We present an approach to enhancing information access through Web structure mining in contrast to traditional approaches involving usage mining. Specifically, we mine the hardwired hierarchical hyperlink structure of Web sites to identify patterns of term-term co-occurrences we call Web functional dependencies (FDs). Intuitively, a Web FD ‘x → y’ declares that all paths through a site involving a hyperlink labeled x also contain a hyperlink labeled y. The complete set of FDs satisfied by a site help characterize (flexible and expressive) interaction paradigms supported by a site, where a paradigm is the set of explorable sequences therein. We describe algorithms for mining FDs and results from mining several hierarchical Web sites and present several interface designs that can exploit such FDs to provide compelling user experiences. [ABSTRACT FROM AUTHOR]

Documents discussing public affairs, common themes, interesting products, and so on, are reported and distributed on the Web. Positive and negative opinions embedded in documents are useful references and feedbacks for governments to improve their services, for companies to market their products, and for customers to purchase their objects. Web opinion mining aims to extract, summarize, and track various aspects of subjective information on the Web. Mining subjective information enables traditional information retrieval (IR) systems to retrieve more data from human viewpoints and provide information with finer granularity. Opinion extraction identifies opinion holders, extracts the relevant opinion sentences, and decides their polarities. Opinion summarization recognizes the major events embedded in documents and summarizes the supportive and the nonsupportive evidence. Opinion tracking captures subjective information from various genres and monitors the developments of opinions from spatial and temporal dimensions. To demonstrate and evaluate the proposed opinion mining algorithms, news and bloggers' articles are adopted. Documents in the evaluation corpora are tagged in different granularities from words, sentences to documents. In the experiments, positive and negative sentiment words and their weights are mined on the basis of Chinese word structures. The f-measure is 73.18% and 63.75% for verbs and nouns, respectively. Utilizing the sentiment words mined together with topical words, we achieve f-measure 62.16% at the sentence level and 74.37% at the document level. [ABSTRACT FROM AUTHOR]

The Internet is increasingly being recognized for its potential for health communication and education. The perceived relative advantage of the Internet over other media is its cost-effectiveness and interactivity, which in turn contribute to its persuasive capabilities. Ironically, despite its potential, we are nowhere nearer understanding how interactivity affects processing of health information and its contribution in terms of health outcomes. An experiment was conducted to examine the effects of Web interactivity on comprehension of and attitudes towards two health Web sites, and whether individual differences might moderate such effects. Two sites on skin cancer were designed with different levels of interactivity and randomly assigned to 441 undergraduate students (aged 18–26) at a large southeastern university. The findings suggest that interactivity can significantly affect comprehension as well as attitudes towards health Web sites. The article also discusses insights into the role of interactivity on online health communications, and presents implications for the effective design of online health content. [ABSTRACT FROM AUTHOR]

It has been claimed that topic metadata can be used to improve the accuracy of text searches. Here, we test this claim by examining the contribution of metadata to effective searching within Web sites published by a university with a strong commitment to and substantial investment in metadata. The authors use four sets of queries, a total of 463, extracted from the university's official query logs and from the university's site map. The results are clear: The available metadata is of little value in ranking answers to those queries. A follow-up experiment with the Web sites published in a particular government jurisdiction confirms that this conclusion is not specific to the particular university. Examination of the metadata present at the university reveals that, in addition to implementation deficiencies, there are inherent problems in trying to use subject and description metadata to enhance the searchability of Web sites. Our experiments show that link anchor text, which can be regarded as metadata created by others, is much more effective in identifying best answers to queries than other textual evidence. Furthermore, query-independent evidence such as link counts and uniform resource locator (URL) length, unlike subject and description metadata, can substantially improve baseline performance. [ABSTRACT FROM AUTHOR]

In recent years, a considerable body of Webometric research has used hyperlinks to generate indicators for the impact of Web documents and the organizations that created them. The relationship between this Web impact and other, offline impact indicators has been explored for entire universities, departments, countries, and scientific journals, but not yet for individual scientists—an important omission. The present research closes this gap by investigating factors that may influence the Web impact (i.e., inlink counts) of scientists' personal homepages. Data concerning 456 scientists from five scientific disciplines in six European countries were analyzed, showing that both homepage content and personal and institutional characteristics of the homepage owners had significant relationships with inlink counts. A multivariate statistical analysis confirmed that full-text articles are the most linked-to content in homepages. At the individual homepage level, hyperlinks are related to several offline characteristics. Notable differences regarding total inlinks to scientists' homepages exist between the scientific disciplines and the countries in the sample. There also are both gender and age effects: fewer external inlinks (i.e., links from other Web domains) to the homepages of female and of older scientists. There is only a weak relationship between a scientist's recognition and homepage inlinks and, surprisingly, no relationship between research productivity and inlink counts. Contrary to expectations, the size of collaboration networks is negatively related to hyperlink counts. Some of the relationships between hyperlinks to homepages and the properties of their owners can be explained by the content that the homepage owners put on their homepage and their level of Internet use; however, the findings about productivity and collaborations do not seem to have a simple, intuitive explanation. Overall, the results emphasize the complexity of the phenomenon of Web linking, when analyzed at the level of individual pages. [ABSTRACT FROM AUTHOR]

Web citations have become common in scholarly publications as the amount of online literature increases. Yet, such links are not persistent and many decay over time, causing accessibility problems for readers. The present study investigates the link decay phenomenon in three leading information science journals. Articles spanning a period of 7 years (1997–2003) were downloaded, and their links were extracted. From these, a measure of link decay, the half-life, was computed to be approximately 5 years, which compares favorably against other disciplines (1.4–4.8 years). The study also investigated types of link accessibility errors encountered as well as examined characteristics of links that may be associated with decay. It was found that approximately 31% of all citations were not accessible during the time of testing, and the majority of errors were due to missing content (HTTP Error Code 404). Citations from the edu domain were also found to have the highest failure rates of 36% when compared with other popular top-level domains. Results indicate that link decay is a problem that cannot be ignored, and implications for journal authors and readers are discussed. [ABSTRACT FROM AUTHOR]

Ethical aspects of the employment of Web crawlers for information science research and other contexts are reviewed. The difference between legal and ethical uses of communications technologies is emphasized as well as the changing boundary between ethical and unethical conduct. A review of the potential impacts on Web site owners is used to underpin a new framework for ethical crawling, and it is argued that delicate human judgment is required for each individual case, with verdicts likely to change over time. Decisions can be based upon an approximate cost-benefit analysis, but it is crucial that crawler owners find out about the technological issues affecting the owners of the sites being crawled in order to produce an informed assessment. [ABSTRACT FROM AUTHOR]

An evaluation methodology based on fuzzy computing with words aimed at measuring the information quality of Web sites containing documents is presented. This methodology is qualitative and user oriented because it generates linguistic recommendations on the information quality of the content-based Web sites based on users' perceptions. It is composed of two main components, an evaluation scheme to analyze the information quality of Web sites and a measurement method to generate the linguistic recommendations. The evaluation scheme is based on both technical criteria related to the Web site structure and criteria related to the content of information on the Web sites. It is user driven because the chosen criteria are easily understandable by the users, in such a way that Web visitors can assess them by means of linguistic evaluation judgments. The measurement method is user centered because it generates linguistic recommendations of the Web sites based on the visitors' linguistic evaluation judgments. To combine the linguistic evaluation judgments we introduce two new majority guided linguistic aggregation operators, the Majority guided Linguistic Induced Ordered Weighted Averaging (MLIOWA) and weighted MLIOWA operators, which generate the linguistic recommendations according to the majority of the evaluation judgments provided by different visitors. The use of this methodology could improve tasks such as information filtering and evaluation on the World Wide Web. [ABSTRACT FROM AUTHOR]

Homepages usually describe important semantic information about conceptual or physical entities; hence, they are the main targets for searching and browsing. To facilitate semantic-based information retrieval (IR) at a Web site, homepages can be identified and classified under some predefined concepts and these concepts are then used in query or browsing criteria, e.g., finding professor homepages containing “information retrieval.” In some Web sites, relationships may also exist among homepages. These relationship instances (also known as homepage relationships) enrich our knowledge about these Web sites and allow more expressive semantic-based IR. In this article, we investigate the features to be used in mining homepage relationships. We systematically develop different classes of inter-homepage features, namely, navigation, relative-location, and common-item features. We also propose deriving for each homepage a set of support pages to obtain richer and more complete content about the entity described by the homepage. The homepage together with its support pages are known to be a Web unit. By extracting inter-homepage features from Web units, our experiments on the WebKB dataset show that better homepage relationship mining accuracies can be achieved. [ABSTRACT FROM AUTHOR]

Recent studies suggest that the wide variability in type, detail, and reliability of online information motivate expert searchers to develop procedural search knowledge. In contrast to prior research that has focused on finding relevant sources, procedural search knowledge focuses on how to order multiple relevant sources with the goal of retrieving comprehensive information. Because such procedural search knowledge is neither spontaneously inferred from the results of search engines, nor from the categories provided by domain-specific portals, the lack of such knowledge leads most novice searchers to retrieve incomplete information. In domains like healthcare, such incomplete information can lead to dangerous consequences. To address the above problem, a new kind of domain portal called a Strategy Hub was developed and tested. Strategy Hubs provide critical search procedures and associated high-quality links to enable users to find comprehensive and accurate information. We begin by describing how we collaborated with physicians to systematically identify generalizable search procedures to find comprehensive information about a disease, and how these search procedures were made available through the Strategy Hub. A controlled experiment suggests that this approach can improve the ability of novice searchers in finding comprehensive and accurate information, when compared to general-purpose search engines and domain-specific portals. We conclude with insights on how to refine and automate the Strategy Hub design, with the ultimate goal of helping users find more comprehensive information when searching in unfamiliar domains. [ABSTRACT FROM AUTHOR]

This article explores the associations that message features and Web structural features have with perceptions of Web site credibility. In a within-subjects experiment, 84 participants actively located health-related Web sites on the basis of two tasks that differed in task specificity and complexity. Web sites that were deemed most credible were content analyzed for message features and structural features that have been found to be associated with perceptions of source credibility. Regression analyses indicated that message features predicted perceived Web site credibility for both searches when controlling for Internet experience and issue involvement. Advertisements and structural features had no significant effects on perceived Web site credibility. Institution-affiliated domain names (.gov, .org, .edu) predicted Web site credibility, but only in the general search, which was more difficult. Implications of results are discussed in terms of online credibility research and Web site design. [ABSTRACT FROM AUTHOR]

A novel metric for quantitatively measuring the content accessibility of the Web for persons with disabilities is proposed. The metric is based on the Web Content Accessibility Guidelines (WCAG) checkpoints, an internationally accepted standard, that can be automatically tested using computer programs. Problems with current accessibility evaluation and the need for a good Web accessibility metric are discussed. The proposed metric is intended to overcome the deficiencies of the current measurements used in Web accessibility studies. The proposed metric meets the requirements as a measurement for scientific research. Examples of large-scale Web accessibility evaluations using the metric are given. The examples cover a comparison of Web accessibility of top medical journal Web sites and a longitudinal study of a Web site over time. The validity of the metric was tested using a large number of Web sites with different levels of compliance (rating categories) to the standard WCAG. The metric, which uses a predetermined simple weighting scheme, compares well to the more complex C5.0 machine learning algorithm in separating Web sites into different rating categories. [ABSTRACT FROM AUTHOR]

Some collections cover many topics, while others are narrowly focused on a limited number of topics. We introduce the concept of the “scope” of a collection of documents and we compare two ways of measuring it. These measures are based on the distances between documents. The first uses the overlap of words between pairs of documents. The second measure uses a novel method that calculates the semantic relatedness to pairs of words from the documents. Those values are combined to obtain an overall distance between the documents. The main validation for the measures compared Web pages categorized by Yahoo. Sets of pages sampled from broad categories were determined to have a higher scope than sets derived from subcategories. The measure was significant and confirmed the expected difference in scope. Finally, we discuss other measures related to scope. [ABSTRACT FROM AUTHOR]

Eleven middle school children constructed hierarchical maps for two science categories selected from two Web directories, Yahooligans! and KidsClick! For each category, children constructed a pair of maps: one without links and one with links. Forty-four maps were analyzed to identify similarities and differences. The structures of the maps were compared to the structures employed by the directories. Children were able to construct hierarchical maps and articulate the relationships among the concepts. At the global level (whole map), children's maps were not alike and did not match the structures of the Web directories. At the local levels (superordinate and subordinate), however, children shared similarities in the conceptual configurations, especially for the concrete concepts. For these concepts, substantial overlap was found between the children's structures and those employed in the directories. For the abstract concepts the configurations were diverse and did not match those in the directories. The findings of this study have implications for design of systems that are more supportive of children's conceptual structures. [ABSTRACT FROM AUTHOR]

Our purpose in this study is to inductively reorganize software interface menu items based on a user's process model. The proposed menu interface in this study used direct users' input, such as goals and strategies for solving their information needs, to reorganize and re-label menus. To assess its effectiveness, efficiency, and user satisfaction with actual users, we implemented and compared this new menu version to the original interface that was based upon a traditional categorical menu organization. The significance of this study is that it incorporates user process modeling into the design of the user interface, providing insights into the impact of such modeling on the usability of an information system. Results from the usability testing do indicate that the proposed menu and the traditional menu are similarly effective for users in terms of task completion time and accuracy. User preferences and debriefing comments from usability testing also indicate users preferred the user-process based arrangement of menu items as displayed. However, the types of tasks (different problem type) suggest significant differences for results in task completion time and in accuracy, sometimes favoring the new version. In other words, usable and effective menu organization depends more on the types of tasks and the domain of knowledge than mere menu organization, although menu organization is a factor in the process. [ABSTRACT FROM AUTHOR]

The rapid development of Web sites providing extensive coverage of a topic, coupled with the development of powerful search engines (designed to help users find such Web sites), suggests that users can easily find comprehensive information about a topic. In domains such as consumer healthcare, finding comprehensive information about a topic is critical as it can improve a patient's judgment in making healthcare decisions, and can encourage higher compliance with treatment. However, recent studies show that despite using powerful search engines, many healthcare information seekers have difficulty finding comprehensive information even for narrow healthcare topics because the relevant information is scattered across many Web sites. To date, no studies have analyzed how facts related to a search topic are distributed across relevant Web pages and Web sites. In this study, the distribution of facts related to five common healthcare topics across high-quality sites is analyzed, and the reasons underlying those distributions are explored. The analysis revealed the existence of few pages that had many facts, many pages that had few facts, and no single page or site that provided all the facts. While such a distribution conforms to other information-related phenomena, a deeper analysis revealed that the distributions were caused by a trade-off between depth and breadth, leading to the existence of general, specialized, and sparse pages. Furthermore, the results helped to make explicit the knowledge needed by searchers to find comprehensive healthcare information, and suggested the motivation to explore distribution-conscious approaches for the development of future search systems, search interfaces, Web page designs, and training. [ABSTRACT FROM AUTHOR]

The value of low frequency words for subject-based academic Web site clustering is assessed. A new technique is introduced to compare the relative clustering power of different vocabularies. The technique is designed for word frequency tests in large document clustering exercises. Results for the Australian and New Zealand academic Web spaces indicate that low frequency words are useful for clustering academic Web sites along subject lines; removing low frequency words results in sites becoming, on average, less dissimilar to sites from other subjects. [ABSTRACT FROM AUTHOR]