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Proofs of Data Reliability are cryptographic protocols that provide assurance to a user that a cloud storage system correctly stores her data and has provisioned sufficient redundancy to be able to guarantee reliable storage service. In this paper, we consider distributed cloud storage systems that make use of erasure codes to guarantee data reliability. We propose two novel Proof of Data Reliability schemes, namely POROS and PORTOS, that on the one hand guarantees the retrieval of the outsourced data in their entirety through the use of proofs of data possession and on the other hand ensures the actual storage of redundancy. As a result, POROS and PORTOS are compatible with the current cloud computing model where the cloud autonomously performs all maintenance operations without any interaction with the user. Moreover, POROS and PORTOS delegate the burden of generating the redundancy to the cloud as well. The security of both solutions is proved in the face of a rational adversary whereby the cheating cloud provider tries to gain storage savings without increasing its total operational cost. [ABSTRACT FROM AUTHOR]

This paper investigates error correction in two‐dimensional (2‐D) intersymbol interference (ISI) channels using polar codes. 2‐D channels offer high data storage capacity compared to traditional one‐dimensional (1‐D) channels but suffer from greater ISI effects. Error correction codes can be used to mitigate the effects of ISI in 2‐D data storage systems and improve their performance and reliability. Polar codes achieve the symmetric capacity for the class of binary‐input discrete memoryless channels (B‐DMCs). A post‐processing technique is proposed to improve the performance of polar codes in the 2‐D ISI channel. The simplified successive cancellation (SSC) polar decoder is useful for data storage systems owing to its good waterfall region performance, low error floors and good throughput rates and is therefore adopted for the study. Simulation results indicate that the proposed technique has an error correction performance comparable to some existing decoders and has better performance than other decoding techniques. [ABSTRACT FROM AUTHOR]

In this paper, we perform an in-depth study into how clinicians represent their information needs and the influence this has on information retrieval (IR) effectiveness. While much research in IR has considered the effectiveness of IR systems, there is still a significant gap in the understanding of how users contribute to the effectiveness of these systems. The paper aims to contribute to this by studying how clinicians search for information. Multiple representations of an information need-from verbose patient case descriptions to ad-hoc queries-were considered in order to understand their effect on retrieval. Four clinicians provided queries and performed relevance assessment to form a test collection used in this study. The different query formulation strategies of each clinician, and their effectiveness, were investigated. The results show that query formulation had more impact on retrieval effectiveness than the particular retrieval systems used. The most effective queries were short, ad-hoc keyword queries. Different clinicians were observed to consistently adopt specific query formulation strategies. The most effective queriers were those who, given their information need, inferred novel keywords most likely to appear in relevant documents. This study reveals aspects of how people search within the clinical domain. This can help inform the development of new models and methods that specifically focus on the query formulation process to improve retrieval effectiveness. [ABSTRACT FROM AUTHOR]

Data containing geospatial semantics, such as geotagged tweets, travel blogs, and crime reports, associates natural language texts with geographical locations. This paper presents a lens‐based visual interaction technique, GTMapLens, to flexibly browse the geo‐text data on a map. It allows users to perform dynamic focus+context exploration by using movable lenses to browse geographical regions, find locations of interest, and perform comparative and drill‐down studies. Geo‐text data is visualized in a way that users can easily perceive the underlying geospatial semantics along with lens moving. Based on a requirement analysis with a cohort of multidisciplinary domain experts, a set of lens interaction techniques are developed including keywords control, path management, context visualization, and snapshot anchors. They allow users to achieve a guided and controllable exploration of geo‐text data. A hierarchical data model enables the interactive lens operations by accelerated data retrieval from a geo‐text database. Evaluation with real‐world datasets is presented to show the usability and effectiveness of GTMapLens. [ABSTRACT FROM AUTHOR]

Conventional approaches to relevance ranking typically optimize ranking models by each query separately. The traditional cluster hypothesis also does not consider the dependency between related queries. The goal of this paper is to leverage similar search intents to perform ranking consistency so that the search performance can be improved accordingly. Different from the previous supervised approach, which learns relevance by click‐through data, we propose a novel cocluster hypothesis to bridge the gap between relevance ranking and ranking consistency. A nearest‐neighbors test is also designed to measure the extent to which the cocluster hypothesis holds. Based on the hypothesis, we further propose a two‐stage unsupervised approach, in which two ranking heuristics and a cost function are developed to optimize the combination of consistency and uniqueness (or inconsistency). Extensive experiments have been conducted on a real and large‐scale search engine log. The experimental results not only verify the applicability of the proposed cocluster hypothesis but also show that our approach is effective in boosting the retrieval performance of the commercial search engine and reaches a comparable performance to the supervised approach. [ABSTRACT FROM AUTHOR]

The segment of companies providing storage services and hardware for end users and small businesses has been growing in the past few years. Cloud storage, personal network-attached storage ( NAS), and external hard drives are more affordable than ever before and one would think that backing up personal digital information is a straightforward process nowadays. Despite this, small group studies and corporate surveys show the opposite. In this paper we present the results from a quantitative and qualitative survey of 319 participants about how they back up their personal computers and restore personal information in case of computer failures. The results show that the majority of users do manual, selective, and noncontinuous backups, rely on a set of planned and unplanned backups (as a consequence of other activities), have inadequate knowledge about possible solutions and implications of using known solutions, and so on. The study also reveals that around a fifth of all computers are not backed up, and a quarter of most important files and a third of most important folders at the time of the survey could not be (fully) restored in the event of computer failure. Based on the results, several implications for practice and research are presented. [ABSTRACT FROM AUTHOR]

This paper provides empirical support for some of the key assumptions guiding the design of data fusion methods. It computes and analyzes the overlap structures between the search results of retrieval systems that participated in the short, long, and manual tracks in TREC 3, 6, 7, and 8 to examine what can be learned to infer a document's probability of being relevant. This paper shows that the potential relevance of a document increases exponentially as the number of systems retrieving it increases—called the Authority Effect. It also shows that documents higher up in ranked lists and found by more systems are more likely to be relevant—called the Ranking Effect. A contribution of this paper is that it shows that the Authority and Ranking Effects can be observed regardless of whether a query is generated manually or automatically and short or long queries are used. Further, it is illustrated that the Authority and Ranking Effects can be observed if the result sets of random groupings of five retrieval systems are compared and only the top 50 results are used in the overlap computation. Also discussed is how the Authority and Ranking Effects can help explain why major data fusion methods perform well. [ABSTRACT FROM AUTHOR]

Research patterns could enhance understanding of the Information Systems (IS) field. Citation analysis is the methodology commonly used to determine such research patterns. In this study, the citation methodology is applied to one of the top-ranked Information Systems conferences—International Conference on Information Systems (ICIS). Information is extracted from papers in the proceedings of ICIS 2000 to 2002. A total of 145 base articles and 4,226 citations are used. Research patterns are obtained using total citations, citations per journal or conference, and overlapping citations. We then provide the citation ranking of journals and conferences. We also examine the difference between the citation ranking in this study and the ranking of IS journals and IS conferences in other studies. Based on the comparison, we confirm that IS research is a multidisciplinary research area. We also identify the most cited papers and authors in the IS research area, and the organizations most active in producing papers in the top-rated IS conference. We discuss the findings and implications of the study. [ABSTRACT FROM AUTHOR]

In this paper the authors propose a search system composed of a self-organizing information retrieval network as a method to effectively search for information managed in a distributed fashion. An information retrieval network is a virtual network consisting of World Wide Web (WWW) server hosts that have search functions. A search system making use of the features of the authors' method can provide the following benefits: (1) information searches on a newly added WWW server host; (2) information searches that avoid a problem host; (3) information searches from any host. In this paper the authors demonstrate the validity of their idea by creating an information search system based on their idea and performing experiments on a university LAN. © 2000 Scripta Technica, Electron Comm Jpn Pt 1, 84(3): 29–37, 2001 [ABSTRACT FROM AUTHOR]

In both the popular press and scholarly research, digital information is persistently discussed in terms that imply its immateriality. In this characterization, the digital derives its power from its nature as a mere collection of 0s and 1s wholly independent from the particular media on which it is stored-hard drive, network wires, optical disk, etc.-and the particular signal carrier which encodes bits-variations of magnetic field, voltages, or pulses of light. This purported immateriality endows bits with considerable advantages: they are immune from the economics and logistics of analog media, and from the corruption, degradation, and decay that necessarily result from the handling of material carriers of information, resulting in a worldwide shift 'from atom to bits' as captured by Negroponte. This is problematic: however immaterial it might appear, information cannot exist outside of given instantiations in material forms. But what might it mean to talk of bits as material objects? In this paper I argue that bits cannot escape the material constraints of the physical devices that manipulate, store, and exchange them. Such an analysis reveals a surprising picture of computing as a material process through and through. [ABSTRACT FROM AUTHOR]

Statistical process control charts are intended to assist operators in detecting process changes. If a process change does occur, the control chart should detect the change quickly. Owing to the recent advancements in data retrieval and storage technologies, today's industrial processes are becoming increasingly autocorrelated. As a result, in this paper we investigate a process-monitoring tool for autocorrelated processes that quickly responds to process mean shifts regardless of the magnitude of the change, while supplying useful diagnostic information upon signaling. A likelihood ratio approach was used to develop a phase II control chart for a permanent step change in the mean of an ARMA ( p, q) (autoregressive-moving average) process. Monte Carlo simulation was used to evaluate the average run length (ARL) performance of this chart relative to that of the more recently proposed ARMA chart. Results indicate that the proposed chart responds more quickly to process mean shifts, relative to the ARMA chart, while supplying useful diagnostic information, including the maximum likelihood estimates of the time and the magnitude of the process shift. These crucial change point diagnostics can greatly enhance the special cause investigation. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper aims to review the fiercely discussed question of whether the ranking of Wikipedia articles in search engines is justified by the quality of the articles. After an overview of current research on information quality in Wikipedia, a summary of the extended discussion on the quality of encyclopedic entries in general is given. On this basis, a heuristic method for evaluating Wikipedia entries is developed and applied to Wikipedia articles that scored highly in a search engine retrieval effectiveness test and compared with the relevance judgment of jurors. In all search engines tested, Wikipedia results are unanimously judged better by the jurors than other results on the corresponding results position. Relevance judgments often roughly correspond with the results from the heuristic evaluation. Cases in which high relevance judgments are not in accordance with the comparatively low score from the heuristic evaluation are interpreted as an indicator of a high degree of trust in Wikipedia. One of the systemic shortcomings of Wikipedia lies in its necessarily incoherent user model. A further tuning of the suggested criteria catalog, for instance, the different weighing of the supplied criteria, could serve as a starting point for a user model differentiated evaluation of Wikipedia articles. Approved methods of quality evaluation of reference works are applied to Wikipedia articles and integrated with the question of search engine evaluation. [ABSTRACT FROM AUTHOR]

Thomson Reuters' Web of Science (WoS) is undoubtedly a great tool for scientiometrics purposes. It allows one to retrieve and compute different measures such as the total number of papers that satisfy a particular condition; however, it also is well known that this tool imposes several different restrictions that make obtaining certain results difficult. One of those constraints is that the tool does not offer the total count of documents in a dataset if it is larger than 100,000 items. In this article, we propose and analyze different approaches that involve partitioning the search space (using the Source field) to retrieve item counts for very large datasets from the WoS. The proposed techniques improve previous approaches: They do not need any extra information about the retrieved dataset (thus allowing completely automatic procedures to retrieve the results), they are designed to avoid many of the restrictions imposed by the WoS, and they can be easily applied to almost any query. Finally, a description of WoS Query Partitioner, a freely available and online interactive tool that implements those techniques, is presented. [ABSTRACT FROM AUTHOR]

Vast amounts of medical information reside within text documents, so that the automatic retrieval of such information would certainly be beneficial for clinical activities. The need for overcoming the bottleneck provoked by the manual construction of ontologies has generated several studies and research on obtaining semi-automatic methods to build ontologies. Most techniques for learning domain ontologies from free text have important limitations. Thus, they can extract concepts so that only taxonomies are generally produced although there are other types of semantic relations relevant in knowledge modelling. This paper presents a language-independent approach for extracting knowledge from medical natural language documents. The knowledge is represented by means of ontologies that can have multiple semantic relationships among concepts. [ABSTRACT FROM AUTHOR]

Understanding what kinds of Web pages are the most useful for Web search engine users is a critical task in Web information retrieval (IR). Most previous works used hyperlink analysis algorithms to solve this problem. However, little research has been focused on query-independent Web data cleansing for Web IR. In this paper, we first provide analysis of the differences between retrieval target pages and ordinary ones based on more than 30 million Web pages obtained from both the Text Retrieval Conference (TREC) and a widely used Chinese search engine, SOGOU (www.sogou.com). We further propose a learning-based data cleansing algorithm for reducing Web pages that are unlikely to be useful for user requests. We found that there exists a large proportion of low-quality Web pages in both the English and the Chinese Web page corpus, and retrieval target pages can be identified using query-independent features and cleansing algorithms. The experimental results showed that our algorithm is effective in reducing a large portion of Web pages with a small loss in retrieval target pages. It makes it possible for Web IR tools to meet a large fraction of users' needs with only a small part of pages on the Web. These results may help Web search engines make better use of their limited storage and computation resources to improve search performance. [ABSTRACT FROM AUTHOR]

This article describes the aims and objectives of the Text REtrieval Conference (TREC) workshops and its impact in the areas of retrieval system effectiveness, retrieval system evaluation, and support of new retrieval tasks. The first TREC workshop was held in November 1992, and there has been a workshop held annually since then. The cumulative effort represented by the TREC is significant. Approximately 250 distinct groups representing more than 20 different countries have participated in at least one TREC, thousands of individual retrieval experiments have been performed and hundreds of papers have been published in the TREC proceedings. The TREC's impact on information retrieval research has been equally significant. A variety of large test collections have been built for both traditional ad hoc retrieval and new tasks such as cross-language retrieval, speech retrieval and question answering. The TREC has standardized the evaluation methodology used to assess the quality of retrieval results and, through the large repository of retrieval runs, demonstrated both the validity and efficacy of the methodology.

Text classification involves deciding whether or not a document is about a given topic. It is an important problem in machine learning, because automated text classifiers have enormous potential for application in information retrieval systems. It is also an interesting problem for cognitive science, because it involves real world human decision making with complicated stimuli. This paper develops two models of human text document classification based on random walk and accumulator sequential sampling processes. The models are evaluated using data from an experiment where participants classify text documents presented one word at a time under task instructions that emphasize either speed or accuracy, and rate their confidence in their decisions. Fitting the random walk and accumulator models to these data shows that the accumulator provides a better account of the decisions made, and a “balance of evidence” measure provides the best account of confidence. Both models are also evaluated in the applied information retrieval context, by comparing their performance to established machine learning techniques on the standard Reuters-21578 corpus. It is found that they are almost as accurate as the benchmarks, and make decisions much more quickly because they only need to examine a small proportion of the words in the document. In addition, the ability of the accumulator model to produce useful confidence measures is shown to have application in prioritizing the results of classification decisions. [Copyright &y& Elsevier]

This paper proposes a system for information storage and delivery. It is based on the new concept where the information corresponding to 10 still pictures and approximately 3 min of sound ire encoded digitally and printed on a postcard as a dot pattern to be read and restored. The system is called an optical postcard system. In this study, after the basic technologies for the realization of this system are investigated, the printed optical postcard and the reproducing system are cone structed experimentally. As a result of the reproduction experiment, the information recorded on the postcard is read and the original picture and sound signal are played back. This indicates that the information can be delivered by optical postcard. The proposed idea of an information storage/delivery system can be applied not only to postcard-sized sheet, but also to sheets of various sizes. Also, there can be various applications which differ from the use of the traditional information media, e.g., the information delivery media, inserted in a book or magazine. [ABSTRACT FROM AUTHOR]

Objectives: To undertake a bibliometric analysis of the physiotherapy literature at two points in time to identify similarities, differences, and the evolution of scholarship over a 40‐year time‐frame. Method: To undertake a quantitative comparative analysis of the published and indexed scholarship literature contained within Scopus relating to physiotherapy over two 10‐year time windows—1978–1987 and 2008–2017. The method used, bibliometrics, is capable of identifying the nature of scholarship, the key actors, and how the focus and methods used to conduct studies have changed. A specialized bibliographic analysis and visualization tool VosViewer (University of Leiden) was used to analyse the extracted results. Results: There has been a more than 10‐fold increase in the number of papers published across the two time‐frames (3,384 from the 1978 to 1987 period and 38,434 from 2008 to 2017). The focus of publication has moved from a medical disease orientated approach to one more specifically looking at physiotherapy interventions aimed at addressing functional ability. In addition, a more diverse range of research approaches are being used as well as efforts to synthesize findings across multiple studies using systematic reviews and meta‐analytical techniques. Authors now come from a much wider range of countries than they did 40 years ago, and they are more likely to be part of a large international collaborative research teams. Conclusions: This unique and comprehensive analysis of physiotherapy scholarship across two different timeframes has provided important insights into the evolution of the profession, its changing focus and methodological approaches as well as the dramatic increase in activity, growth in research teams and diversity of country origins. For anyone entering the profession at this time, it provides a perspective on the pace of change they are likely to experience in their career ahead. [ABSTRACT FROM AUTHOR]

The article presents an introduction to the 55th vol. of the "Journal of the American Society for Information Science and Technology." This issue of the journal presents papers on the topics of information retrieval and information seeking in industrial environments. Information retrieval involves a specific kind of information seeking, as the user is in direct contact with an information interface and with potential sources of information from the system's database. The user conducts the search using various strategies. But there is also the possibility that information processes will occur resulting in a change in the way the user thinks about the topic of the search. Information seeking in industry environments takes up more and more of working day. Even companies producing industrial products are in fact mainly producing informational elements of some kind, often for the purpose of making decisions or as starting positions for further information seeking. While there may be company mechanisms in place to aid such information seeking, and to make it more efficient, if better information seeking structures were in place, not only would workers waste less time in informational pursuits, but they would also find things, discover new processes. That would benefit the corporations bottom line.

This article presents news briefs related to the American Society for Information Science and Technology's members and chapters. Special Interest Group (SIG)/International Information Issues raised over $7000 in just two months this spring for the 6th International Paper Contest on International Digital Libraries and Information Science and Technology Advances in Developing Countries. With fundraising a continuing process, SIG officials expressed pleasure and expectation for ongoing support from the information community. For its June 2005 meeting, the Los Angeles Chapter of the American Society for Information Science and Technology combined a professional development workshop on Personal Knowledge Management: Coping with Information Overload with a business meeting. Karen Fisher, Joan Durrance and Marian Bouch Hinton are the winners of ALA's 2005 Jesse H. Shera Award for Distinguished Published Research, for their article "Information Grounds and the Use of Need-based Services by Immigrants in Queens, NY: A Context-based, Outcome Evaluation Approach."