Retrieval Methods (retrieval + methods)

Distribution by Scientific Domains


Selected Abstracts


The Pros and Cons of Data Analysis Software for Qualitative Research

JOURNAL OF NURSING SCHOLARSHIP, Issue 4 2000
Winsome St John
Purpose: To explore the use of computer-based qualitative data analysis software packages. Scope: The advantages and capabilities of qualitative data analysis software are described and concerns about their effects on methods are discussed. Findings: Advantages of using qualitative data analysis software include being freed from manual and clerical tasks, saving time, being able to deal with large amounts of qualitative data, having increased flexibility, and having improved validity and auditability of qualitative research. Concerns include increasingly deterministic and rigid processes, privileging of coding, and retrieval methods; reification of data, increased pressure on researchers to focus on volume and breadth rather than on depth and meaning, time and energy spent learning to use computer packages, increased commercialism, and distraction from the real work of analysis. Conclusions: We recommend that researchers consider the capabilities of the package, their own computer literacy and knowledge of the package, or the time required to gain these skills, and the suitability of the package for their research. The intelligence and integrity that a researcher brings to the research process must also be brought to the choice and use of tools and analytical processes. Researchers should be as critical of the methodological approaches to using qualitative data analysis software as they are about the fit between research question, methods, and research design. [source]


Unified linear subspace approach to semantic analysis

JOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 1 2010
Dandan Li
The Basic Vector Space Model (BVSM) is well known in information retrieval. Unfortunately, its retrieval effectiveness is limited because it is based on literal term matching. The Generalized Vector Space Model (GVSM) and Latent Semantic Indexing (LSI) are two prominent semantic retrieval methods, both of which assume there is some underlying latent semantic structure in a dataset that can be used to improve retrieval performance. However, while this structure may be derived from both the term space and the document space, GVSM exploits only the former and LSI the latter. In this article, the latent semantic structure of a dataset is examined from a dual perspective; namely, we consider the term space and the document space simultaneously. This new viewpoint has a natural connection to the notion of kernels. Specifically, a unified kernel function can be derived for a class of vector space models. The dual perspective provides a deeper understanding of the semantic space and makes transparent the geometrical meaning of the unified kernel function. New semantic analysis methods based on the unified kernel function are developed, which combine the advantages of LSI and GVSM. We also prove that the new methods are stable because although the selected rank of the truncated Singular Value Decomposition (SVD) is far from the optimum, the retrieval performance will not be degraded significantly. Experiments performed on standard test collections show that our methods are promising. [source]


Pluralism and diversity: trends in the use and application of ordination methods 1990-2007

JOURNAL OF VEGETATION SCIENCE, Issue 4 2009
Henrik Von Wehrden
Abstract Question: What are the trends and patterns in the application of ordination techniques in vegetation science since 1990? Location: Worldwide literature analysis. Methods: Evaluation of five major journals of vegetation science; search of all ISI-listed ecological journals. Data were analysed with ANCOVAs, Spearman rank correlations, GLMs, biodiversity indices and simple graphs. Results: The ISI search retrieved fewer papers that used ordinations than the manual evaluation of five selected journals. Both retrieval methods revealed a clear trend in increasing frequency of ordination applications from 1990 to the present. Canonical Correspondence Analysis was far more frequently detected by the ISI search than any other method. Applications such as Correspondence Analysis/Reciprocal Averaging and Detrended Correspondence Analysis have increasingly been used in studies published in "applied" journals, while Canonical Correspondence Analysis, Redundancy Analysis and Non-Metric Multidimensional Scaling were more frequently used in journals focusing on more "basic" research. Overall, Detrended Correspondence Analysis was the most commonly applied method within the five major journals, although the number of publications slightly decreased over time. Use of Non-Metric Multidimensional Scaling has increased over the last 10 years. Conclusion: The availability of suitable software packages has facilitated the application of certain techniques such as Non-Metric Multidimensional Scaling. However, choices of ordination techniques are currently less driven by the constraints imposed by the software; there is also limited evidence that the choice of methods follows social considerations such as the need to use fashionable methods. Methodological diversity has been maintained or has even increased over time and reflects the researcher's need for diverse analytical tools suitable to address a wide range of questions. [source]


Development and evolution of a heterogeneous continuous media server: a case study

JOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 2 2005
Dwight J. Makaroff
Abstract Media server software is significantly complicated to develop and maintain, due to the nature of the many interface aspects which must be considered. This paper provides a case study of the design, implementation, and evolution of a continuous media file server. We place emphasis on the evolution of the software and our approach to maintainability. The user interface is a major consideration, even though the server software would appear isolated from that factor. Since continuous media servers must send the raw data to a client application over a network, the protocol considerations, hardware interface, and data storage/retrieval methods are of the paramount importance. In addition, the application programmer's interface to the server facilities has an impact on both the internal design and the performance of such a server. We discuss our experiences and insight into the development of such software products within a small research-based university environment. We experienced two main types of evolutionary change: requirements changes from the limited user community and performance enhancements/corrections. While the former were anticipated via a generic interface and modular design structure, the latter were surprising and substantially more difficult to solve. Copyright © 2005 John Wiley & Sons, Ltd. [source]