025.431: The Dewey blog

WebDewey Number Building and Two Add Tables in History

If you go to the span record 930-990 History of specific continents, countries, localities; extraterrestrial worlds and click Start, you can begin to build a number (as described in blog post "WebDewey Number Building Tool: History Numbers Built with Table 2 plus Notation for Historical Period").

However, if you go to the span record 940-990 History of specific continents, countries, localities in modern world; extraterrestrial worlds and click Start, you will get an error message: "This span can’t be used in number building."

Why the difference?  At 930-990 the add note specifies a base number:

"Add to base number 9 notation T2--3-T2--9 from Table 2, e.g., general history of Europe 940, of England 942, of Norfolk, England 942.61; then add further as follows:"

At 940-990 the add note does not specify a base number:

"Except for modifications shown under specific entries, add to each subdivision identified by ‡ as follows:"

Does that mean you really cannot use the add table under 940-990 to build numbers with the number building tool, as the error message might seem to say?  No, not at all.  But first you must find the base number that you need—a subdivision  identified by ‡ with the footnote add instruction: "‡Add as instructed under 940-990."

For example, let’s say you want to build a number for War and Nationalism: The Balkan Wars, 1912-1913, and Their Sociopolitical Implications. The first LCSH is Balkan Peninsula – History – War of 1912-1913.

Step 1. Browse the Relative Index (or search) for "Balkan Wars" or "Balkan Peninsula" to find the base number that you need, with the footnote add instruction:

949.6039 ‡Balkan Wars, 1912-1913

‡Add as instructed under 940-990

Step 2. Click Start in the record for 949.6039. The base number 949.6039 appears in the title bar of the Create built number box. The base number, its caption, and the footnote add instruction appear inside the Create built number box:

Step 3. The number building tool takes us to the full record for 940-990 History of specific continents, countries, localities in modern world; extraterrestrial worlds.  The add table is displayed in the Notes box.  In the Notes box click on add table notation 1. The Hierarchy box shows that you have selected 940-990:1 Social, political, economic history:

The notes for that entry are displayed in the Notes box:

Step 4. In the Create built number box, click Add. In the title bar of the Create built number box, the number has changed to: 949.60391. The add table notation and its caption appear inside the Create built number box:

The number building tool gives the option to add notation from Table 1, but that is not needed for this example.  The built number is complete. 

Step 5. In the Create built number box, click Save.  The newly built number appears in the Hierarchy box:

We have an opportunity to change the user term and add other user terms to the built number.  A summary of the pieces used to build the number remains with the record:

Key to success: at the beginning, get both the base number and the add note inside the Create built number box.

Additional resources

• Posts on using the number building tool with standard subdivisions (post 1, post 2, post 3, post 4)
• Posts on using the number building tool in music (part 1, part 2)
• Post on using the number building tool in literature
• Post on using the number building tool for works on natural resources
• WebDewey training modules for the WebDewey number building tool

Answers to Your Questions

On a quarterly basis, we post "Dewey by the Numbers," which gives a snapshot of Dewey’s growth in terms of four types of quantities:

• explicit assignable numbers in the schedules,
• facets (entries in Tables 1–6 or in add tables),
• Relative Index Terms, and
• mapped headings of various stripes.

The 1 March 2016 version of "Dewey by the Numbers" elicited some interesting questions:

• Can you tell whether updates within one edition only contain new numbers, additional notes, comments etc.?
• Or is it possible that an existing number is deleted or changes definition during the same edition of DDC?
• Putting the question another way: If I assigned a DDC number from DDC 23, do I need to consult after each update to make sure that the assigned number still exists with the same meaning like before the update?

Apparently we are really into snapshots. Not only is every "Dewey-by-the-Numbers" table a quantitative snapshot of Dewey at a particular time, but so is a print edition. Although some might think that DDC 23 corresponds to the state of Dewey in 2011, when DDC 23 was printed, to the editorial team, DDC 23 is a living, growing classification system. What the DDC 23 was on 29 February 2016 is not the same as what the DDC 23 was on 1 February 2016. For example, significant changes took place in T2—68 Republic of South Africa and neighboring southern African countries in the interim. (You will be able to find out more about that in a future blog posting.)

What kinds of changes take place in Dewey? Some changes are merely corrections (e.g., deleting an extraneous word, supplying a missing word, correcting typographic errors in words or numbers). But many changes are more substantive. Several Glossary entries explain the types of changes that may be involved:

Revision: The result of editorial work that alters the text of any class of the DDC. There are three degrees of revision: Routine revision is limited to updating terminology, clarifying notes, and providing modest expansions. Extensive revision involves a major reworking of subdivisions but leaves the main outline of the schedule intact. Complete revision (formerly called a phoenix) is a new development; the base number remains unchanged from the previous edition, but virtually all subdivisions are changed.

Relocation: The shifting of a topic from one number to another number that differs from the old number in respects other than length.

Expansion: The development of a class in the schedules or tables to provide further subdivisions.

Discontinuation: The shifting of a topic or the entire contents of a number to a more general number in the same hierarchy, or the complete removal of the topic or number. A topic or number is discontinued because the topic or concept represented by the number has a negligible current literature or represents a distinction that is no longer valid in the literature or common perception of the field.

Schedule reduction: The elimination of certain provisions of a previous edition, often resulting in discontinued numbers.

Reused number: A number with a total change in meaning from one edition to another. Usually numbers are reused only in complete revisions or when the reused number has been vacant for two consecutive editions.

Now back to those questions. Is it possible that an existing number will be deleted during a single Dewey edition? Yes. All of the topics that were in the number may be discontinued and/or relocated to other numbers, such that a number that was once valid may become obsolete. Is it possible that an existing number will change definition during a single Dewey edition? Unless a complete (or extensive) revision is taking place, it is unlikely that an existing number will completely change its definition, but it is not uncommon for a class to change its definition to some extent during an edition; this may be signaled by new notes, the addition or deletion of topics, etc. (Complete or extensive revisions typically are introduced by a draft for comment posted on the Dewey Discussion Papers page.) Given the types of changes that can take place within a single edition, yes, at least in principle, the classifier should always consult WebDewey to ensure that the meaning of the class has not changed in ways that would now make another number more appropriate.

How can someone know that a change has taken place in a class? Any change visible in the printed version of the class description should be reflected in a PDF posted on the Dewey Updates page. Better yet, a new feature will be coming soon to WebDewey to alert users to changes. (Did you find that tantalizing? You should. But we’re not going to say more about that feature until it’s available.)

How can someone know what change has taken place in a class? Changes on the Dewey Updates page must be discerned by comparing a class description there with the previous class description. In WebDewey, history notes (which the user can choose to display or not, as governed by their preferences) record relocations, expansions, and discontinuations; changes in which topics are in which classes can be seen there. We will be adding more history data later in 2016 to capture some of the topics in relocations, expansions, and discontinuations back to Edition 20 that are now missing. (As before, when that’s available, we’ll say more about it.)

Merger of Library of Congress Dewey and CIP Sections

As we occasionally mention, the Dewey editorial office is housed in a unit of the Library of Congress responsible for assigning Dewey numbers to large numbers of titles processed by the library. This past month the Dewey and Cataloging in Publication (CIP) sections of the library merged. We quote here from a statement released by Karl Debus-López, chief of the U.S. Programs, Law, and Literature Division, and Caroline Saccucci, head of the newly merged CIP and Dewey Section, regarding the merger:

Cataloging in Publication and Dewey Sections Merge to Facilitate Greater Collaboration

The Cataloging in Publication (CIP) and Dewey Decimal Classification (DDC) sections of the Library of Congress have merged their operations effective February 7, 2016. This merger will foster greater collaboration between the CIP and Dewey programs as they work together to prepare descriptive and subject metadata for close to 50,000 electronic title galleys received from over 5,300 U.S. publishers, annually at the Library. Through the merger, the two programs will be able to leverage their strengths in support of each other and be better able to create innovative products and services for their clienteles.

The Dewey Decimal Classification system was created in 1876 by Melvil Dewey and remains the predominant classification system for the nation’s public and school libraries. It is also the principal classification system used by libraries outside of the United States in all sectors of librarianship. The Dewey Decimal Classification has been revised and expanded over 23 published editions, incorporating new subjects and concepts with each iteration of the classification. The Cataloging in Publication Program was implemented at the Library of Congress in 1971. Publishers send electronic galleys of their titles prior to their publication for Library catalogers to create metadata in exchange for a copy of the book after it is published. When the book is published, the publisher includes the CIP data on the copyright page thereby facilitating book processing for libraries and book dealers. The CIP data is the principal source of metadata used by libraries nationwide for their own catalog records. Close to 1.8 million titles have received CIP data from the Library of Congress over the last 45 years.

This merger is a logical extension of a greater collaboration that has occurred between the CIP and Dewey programs since 2013 when they were moved into the same division at the Library. Both of these programs serve the nation’s libraries, with a special emphasis on public and school libraries, which are more likely to arrange their collections according to the Dewey Decimal Classification system. The relationship between LC and Dewey is now 86 years old and goes back to 1930 when the Library of Congress began to print DDC numbers on many of its cards, thus making the system immediately available to the nation’s libraries. When the CIP Program began, it recognized that a very large constituency would be best served if every CIP record contained a Dewey number, and this partnership continues today. Most of the DDC assignment done by professional classifiers is generated by Electronic Cataloging in Publication (ECIP) title galleys received through the CIP Program. Furthermore, the Dewey Program maintains an editorial office through a cooperative arrangement with OCLC, Inc. so that classifiers can consult the editors on new and emerging literature, much of which is generated via the CIP Program, and discuss the best way to classify this material.

There are other ways that the CIP and Dewey program staff members have overlapping responsibilities. Dewey classifiers assign Library of Congress Classification to ECIPs cataloged by the National Library of Medicine and have been developing correlation tools to allow for automatic assignment of DDC from Library of Congress Classification. CIP Program Specialist librarians are also being trained on DDC assignment. Dewey classifiers have served as reviewers or points-of-contact for questions from ECIP Cataloging Partnership Program institutions, which arrange their collections according to Dewey. While the distinct identities of the two programs will remain, each will provide support for the other resulting in what Library management believes will be a very successful merger.

Dewey by the Numbers

Here’s a brief snapshot of the DDC 23 EN database (the database associated with the English-language version of DDC 23) as of 1 March 2016