025.431: The Dewey blog

Dewey Summaries published as Linked Data

For a long time, we wanted to do something with Linked Data. That is, apply Linked Data principles to parts of the Dewey Decimal Classification and present the data as a small “terminology service.” The service should respond to regular HTTP requests with either a machine- or a human-readable presentation of Dewey classes. There should be a URI (and, even better, a web page that delivers a useful description) for every Dewey concept, not just single classes. The data should be presented in a format that is capable of handling rich semantic information and in a way that allows users or user agents to just follow their nose to explore the data. For more complex stuff, the service should offer an API-like query access. Finally, the data that are presented should be reusable by anyone for non-commercial purposes.

Some results of these efforts are now available as dewey.info. We had to come up with a URI pattern for the DDC that would generate persistent identifiers for DDC concepts in a distributed environment. Secondly, we wanted to test out the RDF vocabulary SKOS for creating a representational model to express some of the best nuggets of DDC data (language-independent identifiers, multilingual terminology, and semantic relationships). And finally, because Linked Open Data is not really open when you have to ask someone before you can use it, we wanted to test out a Creative Commons license for easier reuse of DDC data for non-commercial purposes.

We chose the DDC Summaries as a first data set to publish according to Linked Data principles. The latest version of the Summaries, i.e., the top three levels of DDC 22, has been available as a web document for some time. To broaden the possible applications of what now essentially is just tag soup (in only one language), every class had to be identified with a URI and the data had to be presented in a reusable way. Please give it a try at dewey.info. An extended overview of the service can be found here, a slightly more technical description is available on the OCLC Developer Network wiki.

What you see now is only the first step. The intention of dewey.info is to be a platform for Dewey data on the web; more is to come in terms of languages, deeper data, and links to other datasets. The DDC has been widely used as a knowledge organization tool, and the way the URIs have been set up should allow the construction of links based on existing metadata in resource descriptions like bibliographic records.

An example: As the World Digital Library is getting ready to deploy RDF views of its data, instead of just including the Dewey number as a literal (or pointing to some other data source), they could include URIs to dewey.info to tap into the SKOS relationships pointing to broader and narrower classes for retrieval interactions, etc. In turn, this establishes a link from a Dewey class to other vocabularies used concurrently for that resource, to Wikipedia, etc. Links can go both ways and benefit all participating data sets, establishing a graph of Linked Data.

EPC Meeting 131

Giles Martin took the photo of EPC at OCLC on June 12, 2009.  Standing, from left to right: Andrea Kappler (Evansville Vanderburgh [IN] Public Library), Sandra Singh (University of British Columbia), Lyn McKinney (Billings [MT] Senior High School), and Welna van Eeden (University of South Africa); seated, from left to right: Karl Debus-López (Library of Congress, standing in for Beacher Wiggins), David Farris (Library and Archives Canada), EPC Vice-Chair Anne Robertson (Australian Committee on Cataloguing), and Deborah Rose-Lefmann (Northwestern University).

It seems like forever since I’ve written something here, and I’m suppressing the urge to report chronologically on my activities since the last time you heard from me (so stay tuned for reports on three very interesting meetings [one in Houston and two in Vienna] in which I participated back in April).  Today, I’m jumping forward to last week with a quick summary of Meeting 131 of the Decimal Classification Editorial Policy Committee (EPC), which was held June 10-12 at OCLC.  The meeting was chaired by EPC Vice-Chair Anne Robertson (Australian Committee on Cataloguing).  EPC Chair Caroline Kent (British Library) and new EPC member Jonathan Furner (UCLA [and yes, former DDC assistant editor and creator of 025.431: The Dewey blog]) were unable to attend in person, but e-mailed voluminous comments that were considered by the committee during the meeting.

EPC reviewed the full version of Table 1 (Standard Subdivisions).  One provision was postponed for discussion at Meeting 132 in November 2009: the use of T1—0286 Waste technology to represent green technology.  We'll have more to say about that issue once we sort out the ripple effects throughout the schedules.  In Table 2 (Geographic Areas, Historical Periods, Persons), EPC looked mostly to the past in reviewing provisions for the ancient world in T2—3.  Some of the ancient world proposals have implications for the modern world versions of the Mediterranean and Black Sea regions, Asia Minor, and Turkey.  EPC also approved some adjustments to German administrative units proposed by colleagues at Deutsche Nationalbibliothek, plus the placement of the Barents Sea region, North Calotte, and Sápmi (Lapland).  EPC approved the full version of Table 3 (Subdivisions for the Arts, for Individual Literatures, for Specific Literary Forms), and an expansion for Hakka (Han Chinese who speak Hakka dialect) in Table 5 (Ethnic and National Groups).

EPC approved updates in the following schedules: 004-006 Computer science, 200 Religion, 300 Social sciences, 301-307 Sociology and anthropology, 320 Political science, 330 Economics, 340 Law, 400 Language, 610 Medicine and health, 780 Music, 800 Literature, and 960 History of Africa.  EPC reviewed preliminary versions of 640 Home and family management, 690 Buildings, 710 Civic and landscape art, and 720 Architecture.  On the recommendation of EPC, we plan to post the sewing and clothing sections of 646 shortly for outside comment.  EPC also reviewed a preliminary proposal for updates to sections of 372.3-372.8 Elementary education in specific subjects.  In addition to comments from members and observers on the private EPC mailing list, EPC’s deliberations were informed by reports from the working groups associated with the European DDC Users’ Group (EDUG) in the areas of law, education, archaeology, and technical issues.

EPC reviewed several research initiatives from the OCLC Office of Research and the Dewey editorial team, plus the latest draft specification for Dewey Uniform Resource Identifiers (URIs).  We’ll be back with more information on these initiatives later.

EPC scheduled a follow-up electronic Meeting 131A (to be held August 3-28, 2009), during which the committee will address use of the term “encompassing” in the DDC, plus minor issues in 400, 710, and 780.  Meeting 132 will be held November 16-17, 2009, at the Library of Congress.

One other major Dewey event took place last week—June 12 was the last day for updating Dewey data in the current Editorial Support System (ESS).  The new ESS, along with new data formats based on the MARC classification and authority formats, is scheduled to be launched on July 5 (another reason for our recent periods of silence on this blog).  Rebecca wrote a bit about the new ESS last month—watch for more reports shortly.

Dewey Breakfast/Update at ALA Annual 2008

Several presentations from the Dewey Breakfast/Update at the American Library Association (ALA) Annual Conference on June 28, 2008, are now up on the Dewey web site. My presentation on groups of people is a preview of the major changes to the treatment of groups of people across the DDC plus our proposed timetable for introduction of the changes. We've discussed these changes in many past entries, most recently in the report on EPC Meeting 129 last month. We expect to post the draft versions of Table 1 —08–09 and 305–306 for final user comment in early August. Juli Beall discussed literary periods—you'll be hearing more from her later this week on one aspect of her presentation, the treatment of literary periods for writers who write under more than one name. Michael Panzer discussed the two sides of Dewey—the language-neutral side and language-dependent side—as an introduction to a research project under way with Deutsche Nationalbibliothek to explore the possibilities of an integrated display of Dewey in several different languages using MelvilClass. 

Diane Vizine-Goetz also demonstrated the latest version of Classify, a prototype classification support service.  Diane posed a series of questions for consideration by the group:

• Include other classification schemes?
• Display unclassed counts/percentages in summary and chart?
• Treat Fic, B, and E as DDC numbers?
• For latest edition, include full and abridged in summary?
• What should be included in details section?
• Include links to other services, e.g., ClassWeb?
• Add feature for class number suggestions?

Please try out Classify and feel free to comment here or directly on the Classify feedback form.

EPC Meeting 129

The Decimal Classification Editorial Policy Committee (EPC)* met at OCLC May 7-9, 2008. EPC approved several adjustments to the proposed overhaul of the treatment of groups of people (including a separate number for intersex people based on feedback from users) plus the implementation plan for the changes. The current plan is to post draft versions of Table 1 and 305-306 on the Dewey web site in August 2008 (with links from the Dewey blog). We will request comments on the content and implementation plan by October 30, 2008—this will permit discussion of user comments at EPC Meeting 130 in November 2008. It is our intention to introduce the changes to the treatment of groups of people throughout the DDC by second quarter calendar year 2009 in WebDewey and Abridged WebDewey. We plan to make final PDFs of Table 1 and 305-306 available on the Dewey web site at the same time the changes are implemented in the web versions of the DDC. The changes introduced in the web versions of the DDC will also appear in the print version of DDC 23 (scheduled to be published in late calendar year 2010).

In addition to the changes to groups of people in Table 1, EPC approved two changes to T1—079 Competition, awards, financial support: clarification of the add instruction from Table 2, and the relocation of festivals from T1—079 to T1—074 Museums, collections, exhibits. Watch this space for more information on these changes. EPC also approved several changes in Table 2 (Geographic Areas, Historical Periods, Persons) for Belgium, South Africa, Sweden, and Clifton Forge, Va. (the last reflects a rare change within administrative units in the U.S.).  In Table 3 (Subdivisions for the Arts, for Individual Literatures, for Specific Literary Forms), EPC approved new provisions for autobiographical fiction, biographical fiction, and alternative histories.  In Table 6 (Languages), EPC approved updates to Indonesian languages and Galician, plus several miscellaneous updates. Similar changes were made to parallel notation in Table 5 (Ethnic and National Groups).

In the schedules, EPC approved updates in the following areas: 004-006 Computer science, 025.4 Subject analysis and control, 160 Logic, 320 Political science, 364.16 Offenses against property, 398.2 Folk literature, 400 Language, 510 Mathematics, 560-590 Life sciences, 610 Medicine and health, 700 The arts, 800 Literature, and 900 History, geography, and auxiliary disciplines. EPC also reviewed reports on work under way in 200 Religion, 340 Law, and 370 Education. The changes in 364.16, along with other updates to the treatment of criminal offenses, will be the focus of the June New and Changed Entries. We will discuss the proposed updates and open issues in several of the aforementioned schedules in the coming weeks in the Dewey blog—stay tuned.

EPC reviewed several research initiatives from the OCLC Office of Research and the Dewey editorial team. Diane Vizine-Goetz presented current work on a prototype classification web service and pilot terminology services. Dewey editorial team members presented progress reports on several current research projects: machine-assisted derivation of the abridged edition, mixed translation models, identification of the relationship of Relative Index terms to Dewey classes, and improvements to Dewey captions. The team also briefed EPC on our new editorial support system, recent changes to the representation of the DDC in MARC21 formats, and a proposed new approach to the display of relocations and discontinuations in DDC class records. Further, the team gave EPC a progress report on the development of DDC training materials being posted online. There was also a lively discussion on how we might facilitate development and sharing of “Dewey neighborhoods” by Dewey users (see the innovative presentation by the Topeka and Shawnee County Public Library at the March 2008 Public Library Association (PLA) Conference).

EPC will hold a follow-up electronic meeting (Meeting 129A) during June 2008 to resolve some minor open issues from Meeting 129. The group will meet next in person at the Library of Congress in November 2008.

*Photo at top of EPC at OCLC on May 8, 2008—standing from left to right: Lyn McKinney (Billings [MT] Senior High School), Sandra Singh (Vancouver [BC] Public Library), David Farris (Library and Archives Canada), Welna van Eeden (University of South Africa), Andrea Kappler (Evansville Vanderburgh [IN] Public Library) and EPC Chair Caroline Kent (British Library). Seated from left to right: Arlene Taylor (University of Pittsburgh SIS, retired), Vice Chair Anne Robertson (Australian Committee on Cataloguing), and Deborah Rose-Lefmann (Northwestern University).

Designing identifiers for the DDC

Although the Dewey Decimal Classification is currently available on the web to subscribers as WebDewey and Abridged WebDewey in the OCLC Connexion service and in an XML version to licensees, OCLC does not provide any “web services” based on the DDC. By web services, we mean presentation of the DDC to other machines (not humans) for uses such as searching, browsing, classifying, mapping, harvesting, and alerting.

In order to build web-accessible services based on the DDC, several elements have to be considered. One of these elements is the design of an appropriate Uniform Resource Identifier (URI) structure for Dewey.

The design goals of mapping the entity model of the DDC into an identifier space can be summarized as follows:

• Common locator for Dewey concepts and associated resources for use in web services and web applications
• Use-case-driven, but not directly related to and outlasting a specific use case (persistency)
• Retraceable path to a concept rather than an abstract identification, reusing a means of identification that is already present in the DDC and available in existing metadata

We have been working closely with our colleagues in the OCLC Office of Research (especially Andy Houghton as well as Eric Childress, Diane Vizine-Goetz, and Stu Weibel) on a preliminary identifier syntax. The basic identifier format we are currently exploring is:

http://dewey.info/{aspect}/{object}/{locale}/{type}/{version}/{resource}

where

• {aspect} is the aspect associated with an {object}—the current value set of aspect contains “concept”, “scheme”, and “index”; additional ones are under exploration
• {object} is a type of {aspect}
• {locale} identifies a Dewey translation
• {type} identifies a Dewey edition type and contains, at a minimum, the values “edn” for the full edition or “abr” for the abridged edition
• {version} identifies a Dewey edition version
• {resource} identifies a resource associated with an {object} in the context of {locale}, {type}, and {version}

Some examples of identifiers for concepts follow:

<http://dewey.info/concept/338.4/en/edn/22/>

This identifier is used to retrieve or identify the 338.4 concept in the English-language version of Edition 22.

 <http://dewey.info/concept/338.4/de/edn/22/>

This identifier is used to retrieve or identify the 338.4 concept in the German-language version of Edition 22.

 <http://dewey.info/concept/333.7-333.9/>

This identifier is used to retrieve or identify the 333.7–333.9 concept across all editions and language versions.

 <http://dewey.info/concept/333.7-333.9/about.skos>

This identifier is used to retrieve a SKOS representation of the 333.7-333.9 concept (using the “resource” element).

There are several open issues at this preliminary stage of development:

Use cases: URIs need to represent the range of statements or questions that could be submitted to a Dewey web service. Therefore, it seems that some general questions have to be answered first: What information does an agent have when coming to a Dewey web service? What kind of questions will such an agent ask?

Placement of the {locale} component: It is still an open question if the {locale} component should be placed after the {version} component instead (<http://dewey.info/concept/338.4/edn/22/en>) to emphasize that the most important instantiation of a Dewey class is its edition, not its language version. From a services point of view, however, it could make more sense to keep the current arrangement, because users are more likely to come to the service with a present understanding of the language version they are seeking without knowing the specifics of a certain edition in which they are trying to find topics.

Identification of other Dewey entities: The goal is to create a locator that does not answer all, but a lot of questions that could be asked about the DDC. Which entities are missing but should be surfaced for services or user agents? How will those services or agents interact with them? Should some entities be rendered in a different way as presented? For example, (how) should the DDC Summaries be retrievable? Would it be necessary to make the DDC Manual accessible through this identifier structure?

Moving beyond the Presentation Layer

“Moving beyond the Presentation Layer: Content and Context in the Dewey Decimal Classification (DDC) System” has just been published as a special double issue of Cataloging and Classification Quarterly, v. 42, nos. 3/4.  It will also be available shortly as a monograph. Diane Vizine-Goetz and I co-edited the special issue, and invited a group of researchers and practitioners from Canada, Germany, Sweden, Switzerland, Trinidad and Tobago, the United Kingdom, and the United States to explore the content and context offered by the DDC from a variety of perspectives.  The preface, which is available in full online, provides an in-depth overview of the issue. 

Dewey Web Services

Diane Vizine-Goetz, Andrew Houghton, and I had a meeting earlier this week to brainstorm about Dewey web services (for an explanation of web services and some current examples from the Office of Research, see Lorcan Dempsey’s recent article in NextSpace).

We have two basic “what” and “how” questions: “What do users want in terms of Dewey web services?” and “How would they use the data?” We decided to take the discussion directly to you, dear 025.431 readers. First, here’s a brief reminder about the Dewey data already available for experimentation on the ResearchWorks web site.  We have the top three levels of the DDC available in several languages in the DeweyBrowser.  The DeweyBrowser points to three databases, one of which is the abr14 database, which is a subset of Abridged Edition 14 database.  The subset includes the numbers, captions, Relative Index terms, and mapped terminology associated with schedule numbers 000-999.  The schedule notes (class definitions, number-building instructions, and references to other classes), Manual, and Tables 1-4 are not included in the subset. Using the DeweyBrowser browse box, you can feed a term to the abr14 database, and see where the term falls in Dewey.  A click on a particular category at the third level displays the numbers and captions associated with the term in that section of Dewey. Similarly, you can feed a Dewey number to the database, and see the number and caption.  In either case, you can click on a number in the results set, and see the Relative Index terms and mapped terminology associated with each number.

So we need some information on use cases (the How question) and what you need in terms of Dewey web services to address those cases (the What question).  For example, you might say, I would like a Dewey number resolver that I could access from my catalog to deliver the caption associated with a number back to my users (or the caption plus associated terminology).  But let’s not put words in your mouth—please tell us what you want to do.  We’d love to get a discussion started here, but you can also contact one of us directly.

Gathering Clouds

A few months ago a colleague brought the Dewey cloud created by Steve Thomas to our attention. Steve used the Dewey Summaries to provide a visual presentation of the print collection of the University of Adelaide Library. In OCLC Research, we have also been experimenting with tag clouds. We recently generated Dewey clouds in English, French, German, Spanish, Swedish, and Vietnamese for the top 100 Dewey classes in the WorldCat collection searchable through the DeweyBrowser. We also added some new features to the DeweyBrowser including a library shelf view and the ability to sort the title list. Please let us know what you think of these DeweyBrowser changes.

Improved Access to Fiction

Juli Beall, the second speaker at Saturday's Dewey Breakfast/Update at the ALA Annual Conference in New Orleans, reported on research she and Diane Vizine-Goetz (OCLC Office of Research) are doing on use of the DDC to expand the coverage of FictionFinder to help people interested in looking for a good story.  In her presentation "Using Dewey to Improve Access to Fiction," Juli demonstrated how the DDC can be used to find fiction in the broad sense of the term--"stories of imagined events, e.g., novels, short stories, fairy tales, fables, films, comics, interactive fiction."  Right now, FictionFinder uses the MARC coding for fiction in existing catalog records, thus limiting retrieval to fiction in the narrow sense of novels and short stories.  Juli and Diane are experimenting with adding the following Dewey numbers (and selected subdivisions) to increase retrieval of fiction in the broad sense: 741.5 Comic books, graphic novels, fotonovelas, cartoons, caricatures, comic strips; 741.43 Motion pictures; and 741.45 Television.

So what do Pride and Prejudice and Fantastic Four have in common (we asked this question in the Dewey Breakfast/Update announcement)?  Both are works of fiction in the broad sense, in that they appear in multiple formats.  Pride and Prejudice began as a textual novel, but also has television and film representations.  Fantastic Four started as a comic book, but also has been novelized and made into a film.

Game theory

Lots going on at PLA, which is one of the friendliest and most vibrant conferences your roving reporter from the Dewey blog has had the pleasure to attend. Yesterday turned out to be Generation M Day -- much to learn about how millennials' experience as gamers and internet users has shaped their distinctive attitudes toward life and work and the new ways in which they solve problems, interact with one another, and seek entertainment and information. First up was Lee Rainie, director of the Pew Internet & American Life Project, who summarized the insights that may be drawn from the Pew/Internet data about the attitudes and behavior of Americans born between 1982 and 2000; then John C. Beck, president of the North Star Leadership Group and co-author of Got game: How the gamer generation is reshaping business forever, further highlighted the significance of the new "Generation Gap" between gamers and non-gamers. How should search and access tools be designed so that they help and hold the attention of young people who, forever immersed in networked media, are far more willing and able than their parents to multitask, collaborate, take risks, adapt to change, share and remix creative content ... ? Where does a subject classification scheme like the DDC fit in a world in which people find the stuff they want by connecting with like-minded peers and asking for recommendations? Rest assured: down at the Manor, we're on it.