Adding Value to Open Scholarly Content How Services and Search Expose The Value of the Perseus Digital Library

Mission –To increase accessibility to and interest in the humanities. What makes our content interesting? – We give this content away yet still maintain a user base that finds value in its offerings. What is Perseus?

Perseus’ Static & Dynamic Services Perseus gives away its static content.. Perseus also makes its content dynamically accessible. –Allows for interconnections among Perseus’ objects. –This allows us to build up a network of associations between primary and secondary sources of information. Named Entity Extraction Morphological Analysis –The more content we have, the more associations between objects we can offer.

Increasing the value of Perseus’ texts –The concepts behind the Canonical Text Services protocol (CTS) CTS will allow us to interconnect our objects. –Intra-connecting: Making associations within our own content –Inter-connecting: Making associations between our content and external services/content. The role of search In a time when “scholarly content is increasingly being seen as a public resource,” what is the role of search engines in conceiving and delivering texts? Text Services

By the end of the talk we will see: –A Service for Referencing Text CTS –The Value of Associations CTS URNs, a syntax for intra and inter-connecting texts –Perseus’ other sources of value Perseus’ logical architecture Goals

A Service For Referencing Text

Hierarchical Ontology of Text Organization –An author’s works Get me all works by Julius Caesar urn:cts:latinLit:stoa0069 –A particular work of an author Get me Caesar’s The Gallic War urn:cts:latinLit:stoa0069:stoa002 –An edition or translation of a work Get me a specific English translation of Caesar’s The Gallic War urn:cts:latinLit:stoa0069:stoa002:1999_02_0001 Concepts Behind CTS: Author to Edition

–A logical component of text from an edition or translation in terms of its citation scheme Get me Book 1, Chapter 1 of Caesar’s Gallic War from this English translation urn:cts:latinLit:stoa0069:stoa002:1999_02_0001:1.1 –A paragraph, quotation, or single character within a text “All Gaul is divided into three parts” urn:cts:latinLit:stoa0069:stoa002:1999_02_0001:1.25: All:0-parts:0 –A range of text Give me Book 1, Chapter 37 through Book 2, Chapter 5 of Caesar’s Gallic War urn:cts:latinLit:stoa0069:stoa002: Concepts Behind CTS: Edition to Character

–CTS URNs can be thought of as a syntax for a “new and emerging content delivery mechanism” –Through URNs we can “break down the content into component parts, each of which can be manipulated…separately” –Although CTS adds value to the raw data/content we give away. Logical referencing Enables associations CTS And Content Delivery

The Value of Associations

–Associations between data add value. Google Page Rank –Index services let us construct associations with semantic precision. Named entity disambiguation Citations Morphological Information –Associations add context and increase understanding of the underlying content. Occurrence of Gaul in a text to its definition Occurrence of Gaul on this slide to previous examples. Intra-Connecting Content: The Role of Index Services

–Perseus can increase the value of its content even further by connecting its highly-structured data with external services (like search engines) providing less-structured data –We’ve seen this idea before… Google Earth: Search and display results –Longitude and latitude (Geographic coordinates) CTS-aware searching: Search and display results –CTS URNs (textual coordinates) Inter-Connecting Content: The Role of Search Engines

–What Perseus is doing now (experimental): Using Google Base and CTS-URNs to find Perseus’ highly-structured content with semantic precision. –Search texts at any tier of the hierarchical structure expanding or truncate the URN. –Examples: Get me all works by Julius Caesar visible to this search.all works by Julius Caesar visible to this search Get me Caesar’s The Gallic WarCaesar’s The Gallic War Get me a Perseus-edition English translation of Caesar’s Gallic Wara Perseus-edition English translation of Caesar’s Gallic War Get me Book 1, Chapter 1 of Caesar’s The Gallic War from the English TranslationBook 1, Chapter 1 of Caesar’s The Gallic War from the English Translation CTS URNs and Search

–We have a standard mechanism for referencing and retrieving texts –We have a mechanism for tracking our audience. –A syntax for aggregation of content (Shore) –A well-defined API implementing an open standard (Shore) –Handles multi-lingual content Provides a syntax for datasets of aligned texts. –A notation for semantically precise associations. CTS as a Value-Added Service

Perseus’ Other Sources of Value

DATA LAYER: TEI-XML texts, databases, raw data. Perseus gives away this raw data under the Creative Commons License. –Perseus as a data source to the community –Perseus understands how to create this data and can help others to do so as well DOMAIN LAYER: The objects that encapsulate the data and add a set of behaviors. –The knowledge and experience gained while creating this layer, and coming to understand the objects of the domain. –Working in the domain of Classical texts provides Perseus with a unique perspective on the nature of text that others may find useful. Perseus’ Logical Architecture: Identifying Sources of Value

SERVICE LAYER: The service layer provides an API implementing a series of protocols for each of the types of data Perseus serves. –Others are free to repurpose Perseus’ content through an API that encodes domain knowledge. –The community using the API becomes a source of information and value DISPLAY LAYER: The user interface. Think widgets, HTML web pages, PDFs, etc. –Convenience & Ease of Use –Expertise: The UI reflects the knowledge about the content gained when building the other layers.

–The idea: Perseus can give away its static data because it adds value through providing semantically rich associations, adding context to the content. –An Example Service: The Canonical Text Services’ protocol offers a new way to conceive of, reference, and deliver texts –Associations Add Value: Perseus’ value stems from these associations, the value is not inherent in the raw data, but comes from creating relationships among the data. Search engines give Perseus the opportunity to create semantically precise associations from less-structured, external content to highly-structured Perseus content. This is accomplished through augmenting search queries with the ‘textual coordinates’ of the CTS URN. –Perseus Offers More Than Services: In giving away our raw data, we hope to encourage others to create their own associations, increasing our value as a data provider and as service developers. For the majority of users however, our value stems from providing highly structured texts with rich associations in a simple user interface. Closing Points

–People Blossom, John. “Shoreviews. Content Industry Outlook 2007: Reality Checks.” Shore Communications Inc. 8 Feb Crane, Gregory. Conversations and being in his general vicinity Present. –Interconnecting primary and secondary sources –The Perseus Digital Library Smith, Neel. Conversations and being in his general vicinity Present. –“An Architecture for a distributed library incorporating open-source critical editions.” OSCE position paper. Weaver, Michael. Conversations and being in his general vicinity Present. –Slide layout based on his HTML design –Logical layers of an application as a model for business processes ( –Relevant Links CTS: Google Base: Perseus: Resources