Collection-level Metadata Research Articles

NCI Imaging Data Commons

National Cancer Institute (NCI) Cancer Research Data Commons (CRDC) aims to establish a cloud-based data science infrastructure. Imaging Data Commons (IDC) is a component of CRDC supported by the Cancer Moonshot™, which aims to enable access and exploration of de-identified imaging data, and to support integrated analyses with non-imaging data. IDC will interoperate with other components of CRDC, which include repositories of other types of data, such as genomics and proteomics repositories, and computational resources to perform analysis of the data. IDC builds on the strengths of the established efforts such as The Cancer Imaging Archive (TCIA) to collect and share FAIR (Findable Accessible Interoperable Reusable) imaging data.IDC uses a combination of commercially available tools and capabilities provided by Google Cloud Platform (GCP) together with a range of open-source components. While the initial focus is to support clinical radiology and radiotherapy data, IDC aims to provide similar capabilities for brightfield microscopy, multi-channel immunofluorescence and other imaging modalities. Equally important is the ability to support the results of imaging data analysis, such as annotations of regions of interest in the images or various descriptors of image findings. The IDC search portal provides an interface for exploring the data, defining cohorts, and summarizing attributes of the cohort. Images can be viewed in the integrated browser-based viewer, which uses DICOMweb to access the IDC data. IDC data is public and contains no Protected Health Information (PHI). As CDRC grows, imaging datasets will be increasingly cross-linked to genomic, proteomic, and clinical data about the subjects.The pilot of IDC was released in October 2020, including 28 collections of the TCIA: radiology images related to The Cancer Genome Atlas (TCGA) project, and several collections prioritized to establish the capabilities of IDC in handling image-derived data. DICOM and collection-level metadata is available from the BigQuery tables, and does not require a project configured with billing. The IDC portal is available at https://portal.imagingdatacommons.cancer.gov, and integrates a customized web viewer that supports visualization of both the images and image annotations (specifically, visualization of DICOM Segmentation and Radiotherapy Structure Set is supported, including multiplanar reformatting). IDC also provides documentation and a user forum.The IDC pilot available to the cancer research community explores the promise of cloud-hosted public imaging collections co-located with the compute resources and a growing number of tools to support data analysis. Production release of IDC is planned for Fall 2021, and will include all of the public TCIA collections, including those that contain imaging and annotation data from radiotherapy studies and clinical trials.

More product, more process: metadata in digital image collections

Purpose The purpose of this paper is to discuss the implications of current theories that advocate for minimal levels of description in digital collections. Specifically, this paper looks at the archival theory of “More Product, Less Process” and its encouragement of collection-level description. The purpose of the study was to analyze how levels of description impact resource retrieval. Design/methodology/approach This study analyzed 35 images from a New York Public Library (NYPL) digital collection present on the NYPL website and on Flickr. The methodology was designed to reflect users’ information seeking behavior for image collections. There were two research questions guiding this study: what are the descriptive terms used to describe items in digital collections? and what is the success rate of retrieving resources using assigned descriptive terms? Findings The results of this study revealed that the images from the NYPL collection were more difficult to find on the institution’s website as compared with Flickr. These findings suggest that lesser levels of description in digital collections hinder resource retrieval. Research limitations/implications These findings suggest that lesser description levels hurt the findability of resources. In the wake of theories such as “More Product, Less Process”, information professionals must find ways to assign metadata to individual materials in digital image collections. Originality/value Recent research concerning description levels of digital collections is several years old and focuses mostly on the usefulness of collection-level metadata as a supplement to or substitute for item-level metadata. Few, if any, studies exist that explore the implications of description levels on resource retrievability and findability. This study is also unique in that it discusses these implications in the context of less-is-more theories of archival processing.

Digital Libraries that Demonstrate High Levels of Mutual Complementarity in Collection-level Metadata Give a Richer Representation of their Content and Improve Subject Access for Users

A Review of:
 Zavalina, O. L. (2013). Complementarity in subject metadata in large-scale digital libraries: A comparative analysis. Cataloging & Classification Quarterly, 52(1), 77-89. http://dx.doi.org/10.1080/01639374.2013.848316
 
 Abstract
 
 Objective – To determine how well digital library content is represented through free-text and subject headings. Specifically to examine whether a combination of free-text description data and controlled vocabulary is more comprehensive than free-text description data alone in describing digital collections.
 
 Design – Qualitative content analysis and complementarity comparison.
 
 Setting – Three large scale cultural heritage digital libraries: one in Europe and two in the United States of America. 
 
 Methods – The researcher retrieved XML files of complete metadata records for two of the digital libraries, while the third library openly exposed its full metadata. The systematic samples obtained for all three libraries enabled qualitative content analysis to uncover how metadata values relate to each other at the collection level. The researcher retrieved 99 collection-level metadata records in total for analysis. The breakdown was 39, 33, and 27 records per digital library. When comparing metadata in the free-text Description metadata element with data in four controlled vocabulary elements, Subject, Geographic Coverage, Temporal Coverage and Object Type, the researcher observed three types of complementarity: one-way, two-way and multiple-complementarity. The author refers to complementarity as “describing a collection’s subject matter with mutually complementary data values in controlled vocabulary and free-text subject metadata elements” (Zavalina, 2013, p. 77). For example, within a Temporal Coverage metadata element the term “19th century” would complement a Description metadata element “1850–1899” in the same record.
 
 Main Results – The researcher found a high level of one-way complementarity in the metadata of all three digital libraries. This was mostly demonstrated by free-text data in the Description element complemented by data in the controlled vocabulary elements of Subject, Geographic Coverage, Temporal Coverage, and Object Type. Only one library demonstrated a significant proportion (19%) of redundancy between free-text and controlled vocabulary metadata. An example of redundancy found included a repetition of geographic information in both a Description and Geographic Coverage metadata elements.
 
 Conclusion – The author reports high levels of mutual complementarity in the three cultural heritage digital libraries studied. The findings demonstrate that collection-level metadata which includes both free-text and controlled vocabulary is more representative of the intellectual content of the collections and improves subject access for users. The author maintains that there is no standard for collection-level metadata descriptions, and that this research may contribute to best practice guidelines in this area. It is unclear whether the digital libraries studied had written policies in place on how to describe collections and if those policies were adhered to in practice. The author expresses a need for further research to be conducted on collection-level metadata in other domains, such as science and interdisciplinary digital libraries, and on other scales (e.g., regional or state collections) and geographic regions beyond Europe and the United States.

Verification of a new NOAA/NSIDC passive microwave sea-ice concentration climate record

A new satellite-based passive microwave sea-ice concentration product developed for the National Oceanic and Atmospheric Administration (NOAA) Climate Data Record (CDR) programme is evaluated via comparison with other passive microwave-derived estimates. The new product leverages two well-established concentration algorithms, known as the NASA Team and Bootstrap, both developed at and produced by the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC). The sea-ice estimates compare well with similar GSFC products while also fulfilling all NOAA CDR initial operation capability (IOC) requirements, including (1) self-describing file format, (2) ISO 19115-2 compliant collection-level metadata, (3) Climate and Forecast (CF) compliant file-level metadata, (4) grid-cell level metadata (data quality fields), (5) fully automated and reproducible processing and (6) open online access to full documentation with version control, including source code and an algorithm theoretical basic document. The primary limitations of the GSFC products are lack of metadata and use of untracked manual corrections to the output fields. Smaller differences occur from minor variations in processing methods by the National Snow and Ice Data Center (for the CDR fields) and NASA (for the GSFC fields). The CDR concentrations do have some differences from the constituent GSFC concentrations, but trends and variability are not substantially different.Keywords: Sea ice; Arctic and Antarctic oceans; climate data record; evaluation; passive microwave remote sensing.(Published: 22 December 2014)Citation: Polar Research 2014, 33, 21004, http://dx.doi.org/10.3402/polar.v33.21004

Complementarity in Subject Metadata in Large-Scale Digital Libraries: A Comparative Analysis

Provision of high-quality subject metadata is crucial for organizing adequate subject access to rich content aggregated by digital libraries. A number of large-scale digital libraries worldwide are now generating subject metadata to describe not only individual objects but entire digital collections as an integral whole. However, little research to date has been conducted to empirically evaluate the quality of this collection-level subject metadata. The study presented in this article compares free-text and controlled-vocabulary collection-level subject metadata in three large-scale cultural heritage digital libraries in the United States and the European Union. As revealed by this study, the emerging best practices for creating rich collection-level subject metadata includes describing a collection's subject matter with mutually complementary data values in controlled-vocabulary and free-text subject metadata elements. Three kinds of complementarity were observed in this study: one-way complementarity, two-way complementarity, and multiple complementarity.

Exploring the richness of collection-level subject metadata in three large-scale digital libraries

A growing number of digital libraries worldwide are now generating collection-level metadata to describe entire digital collections as integral wholes. This paper reports results of the study that used an in-depth comparative content analysis to assess free-text and controlled-vocabulary collection-level subject metadata in three large-scale digital libraries in the European Union and the USA. As observed by this study, the emerging best practices in creating collection-level subject metadata include: (a) describing collection's subject matter with mutually complementary values in controlled-vocabulary and free-text metadata; (b) encoding a variety of collection properties in free-text metadata, including both subject properties (topical, geographic and temporal coverage, and types/genres of objects) and non-subject information: title, size, provenance, collection development, copyright, audience, navigation and functionality, language of items in a digital collection, frequency of additions, institutions that host a collection or contribute to it, funding sources, item creators, importance, uniqueness and comprehensiveness of a digital collection.

Concert Programmes Database (review)

Concert Programmes Database. Cardiff University. http://www .concertprogrammes.org.uk/ (Accessed February 2011). [Requires a Web browser and an Internet connection. Pricing: Free]. Concert programs can provide a wealth of information for historical research. Musi cologists, such as Jann Pasler, have used this type of ephemera as an integral part of their research methodology.1 However, primary source materials such as concert programs are seldom consistently collected or preserved in libraries, museums, or archives. The March 1981 issue of Notes contains an article by James J. Fuld entitled Programs and Posters: the Need for an Inventory. In it, Fuld pleads with the library community to recognize the inherent value of collecting and preserving music programs. Fuld states, programs and posters . . . do not seem to have achieved a status in music libraries comparable to their usefulness. While libraries are presumably happy to receive these materials, they may not be well organized, preserved, or completely catalogued. 2 More than twenty years after Fuld's article, the Concert Programmes Project (hereafter CPP) was established in 2003 to address this issue on a national level in the United Kingdom. The Concert Programmes Database (hereafter CPD) was the result of this project. Work on CPD officially began in 2004 with funding from the Arts and Humanities Research Council of the U.K. CPP's mission is twofold: to help researchers locate valuable primary source material relevant to their research, and to assist librarians with determining priorities for collection development and preservation. CPD contains records of concert program holdings in libraries, archives, and museums of the U.K. and Ireland. In 2007, the database was officially launched and is currently hosted by Cardiff University and the Royal College of Music. In order to provide users with valuable collection descriptions and to ensure interoperability with similar databases, CPP implemented a collection-level metadata schema developed by the U.K.'s Research Support Libraries Programme. The schema is also used by Cecilia (http://www.cecilia-uk .org/), an online guide to music collections in archives, libraries, and museums in the U.K. and Ireland. Cecilia's scope is much larger than CPD. According to Rupert Ridgewell, Curator of Music at the British Library, CPD indexes 5,525 collections from fifty-three institutions. 3 The Royal College of Music, the British Library and the Royal Academy of Music are the three largest contributors to the database. The collections contain programs from the seventeenth through the twenty-first centuries from eighty countries. Although this is an impressive number of collections, the database does not include every institution in the U.K. and Ireland with music program holdings. Each collection has a database record that contains three main sections: Summary, Location Details, and Additional Col - lection Information. The Summary contains fields for Collection Title, Unique Identifier, Description, Date Range, Suggested Audience, Associated People or Organisations, Associated Places, and Associated Times. The amount of detail under the Description field varies widely from collection to collection. The Summary also includes a field entitled This collection is about, which is pulled from a limited set of subject headings such as Annotations, Analytical notes, and First performances. Location Details provides contact information on the institution holding the collection. Additional Collection Information provides information on the collection's status, related publications, management information type, owner, creator, collector, custodian, and any associated collections. Users can browse the database using five criteria: Time, People, Place, Subject, and Institution. Time is broken down into fourteen categories and includes time spans such as 17th century-late 1676- 1699, 19th century-late Victorian 1876- 1899, and World War I-1914-18. …

Contextual Metadata in Digital Aggregations: Application of Collection-Level Subject Metadata and Its Role in User Interactions and Information Retrieval

A number of digital libraries that aggregate multiple digital collections are now generating subject metadata to describe intellectual content of entire digital collections as integrated wholes and to provide context for individual digital objects within them. However, the utility of this important contextual metadata has not been empirically evaluated. The exploratory study reported in this article examined and compared collection-level subject metadata in three large-scale aggregations of cultural heritage digital collections in the United States and the European Union and analyzed the role of collection-level metadata in information retrieval in digital aggregations based on user search queries derived from transaction logs. A small-scale targeted user study, which combined interviews and observations of users interacting with an aggregation, was undertaken to complement evidence-based content analysis data. The study revealed considerable variability in two indicators: consistency of applying controlled-vocabulary collection-level subject metadata elements beyond topical and value length of metadata elements. Both free-text and controlled-vocabulary subject metadata were found vital in answering search queries of aggregation users. Users also expressed preference for viewing complete structured collection-level metadata records, which include subject metadata. Results of this study prove importance of provision of collection-level metadata in general and subject metadata in particular to enhance user experiences and information retrieval in digital libraries.

Beyond size and search: Building contextual mass in digital aggregations for scholarly use

At present there are no established collection development methods for building large-scale digital aggregations. However, to realize the potential of the collective base of digital content and advance scholarship, aggregations must do more than provide search of sizable bodies of content. Informed by empirical understanding of scholarly information practices, the IMLS Digital Collections and Content project developed an aggregation strategy for building Opening History, one of the largest digital cultural heritage aggregations in the country. The strategy applied policy-driven collecting, based on the principle of contextual mass, and conspectus-style evaluation of collection-level metadata to identify strong subject areas within the aggregation. Analysis of density, interconnectedness, diversity, and small/large collection complementarity determined subject concentrations and thematic strengths to be prioritized for future collection development and used as organizational structures for browsing and visualization. The approach models how scholars build their own personal research collections, as they follow leads from collection to collection across institutions near and far, and adds value that cannot be achieved through conventional retrieval and browsing at the item-level.

New developments in file-based infrastructure for ATLAS event selection

In ATLAS software, TAGs are event metadata records that can be stored in various technologies, including ROOT files and relational databases. TAGs are used to identify and extract events that satisfy certain selection predicates, which can be coded as SQL-style queries. TAG collection files support in-file metadata to store information describing all events in the collection. Event Selector functionality has been augmented to provide such collection-level metadata to subsequent algorithms. The ATLAS I/O framework has been extended to allow computational processing of TAG attributes to select or reject events without reading the event data. This capability enables physicists to use more detailed selection criteria than are feasible in an SQL query. For example, the TAGs contain enough information not only to check the number of electrons, but also to calculate their distance to the closest jet–a calculation that would be difficult to express in SQL. Another new development allows ATLAS to write TAGs directly into event data files. This feature can improve performance by supporting advanced event selection capabilities, including computational processing of TAG information, without the need for external TAG file or database access.

REPRESENTING CONTEXT-DEPENDENT INFORMATION IN CULTURAL COLLECTIONS

An extension of the Dublin Core Collections Application Profile (DCCAP) suitable for representing context-dependent collection level metadata, is presented in this paper. The extended model, called Multidimensional DCCAP, is based on a multidimensional extension of RDF. Contexts are specified by assigning values to a set of appropriately chosen parameters called dimensions. The proposed extension allows the user to encode metadata for each defined context enriching substantially in this way the expressive power of the metadata model. Multidimensional DCCAP metadata model allows to represent the collection development evolution as well as to keep information created for various users categories, with various degrees of detail, or even in different languages.

Research and usage of collection level metadata in Chinese digital libraries

The World Wide Web and other information technologies have deeply changed our information environment and influenced how we index and access the information we need. The library is a good example of this revolution. Instead of a building that holds books, the library is evolving into an electronic portal to digital materials from across the globe. Facing so many distributed and heterogeneous digital resources, layered metadata are efficient but sophisticated tools that make it easier to find the best information resources. In recent years many types of item-level metadata with which people are familiar have appeared. In contrast to item-level metadata, collection level metadata has not been broadly used, especially in China. By illustrating what a collection is and why we should create collection level metadata, we introduce the research and usage of collection level metadata in China and analyze the problems and limitations of the metadata being used. Some suggestions as to its use are also mentioned.

Research and usage of collection level metadata in Chinese digital libraries

The World Wide Web and other information technologies have deeply changed our information environment and influenced how we index and access the information we need. The library is a good example of this revolution. Instead of a building that holds books, the library is evolving into an electronic portal to digital materials from across the globe. Facing so many distributed and heterogeneous digital resources, layered metadata are efficient but sophisticated tools that make it easier to find the best information resources. In recent years many types of item-level metadata with which people are familiar have appeared. In contrast to item-level metadata, collection level metadata has not been broadly used, especially in China. By illustrating what a collection is and why we should create collection level metadata, we introduce the research and usage of collection level metadata in China and analyze the problems and limitations of the metadata being used. Some suggestions as to its use are also mentioned.

Finding Geographic Information: Collection-Level Metadata

Certain types of information are associated with specific locations on Earth’s surface, and can be retrieved using location as the primary search key. The combination of a collection of such information and a location-based search mechanism is termed a geolibrary. A search for specific information over multiple collections is more efficient if one knows where to look. Information about the contents of a collection is termed collection-level metadata (CLM). Several conceptual designs for the process of search are reviewed, and the U.S. National Geospatial Data Clearinghouse is discussed. The Alexandria Digital Library provides an example of a large digital collection. Its geographic coverage is analyzed to determine whether its CLM can be modeled effectively. The difficulties of describing CLM are discussed from the perspective of institutional change, as library collections attempt to make themselves more accessible through the Internet.

Application of Dublin Core metadata in the description of digital primary sources in elementary school classrooms

Researchers evaluated the ability of 4th and 5th grade science and social science students to create Dublin Core metadata to describe their own images for inclusion in Digital Portfolio Archives. The Dublin Core was chosen because it provided a systematic, yet minimal way for students to describe these resources at the item level and relate them to collection-level metadata prepared for digitized primary sources by archivists using Encoded Archival Description (EAD). Researchers found that while students were able to supply simple elements such as title and subject with relative ease, they had difficulty moving between general and progressively more granular or refined descriptive elements. Students performed poorly in distinguishing between and completing related, but distinct metadata elements, such as title, subject, and description. Researchers also found that there are still significant issues that need to be addressed if young users in a variety of learning contexts, especially those who are only recently literate, are to be able to make sense of richer metadata such as EAD that is used to describe collections of primary source material.