How to edit DBpedia Mappings

In the spirit of open source projects, the idea of this wiki is to enable the interested public to contribute to the definition of DBpedia mappings by updating existing mappings and by adding new mappings to this wiki.

The type of Wikipedia content that is most valuable for the DBpedia extraction are infoboxes and tables. Infoboxes display an article's most relevant facts as a table of attribute-value pairs on the top right-hand side of the Wikipedia page.

As Wikipedia's infobox template system has decentrally evolved over time, different communities of Wikipedia editors use different templates to describe the same type of things (e.g. infobox_city_japan, infobox_swiss_town and infobox_town_de). Different templates use different names for the same attribute (e.g. birthplace and placeofbirth). As many Wikipedia editors do not strictly follow the recommendations given on the page that describes a template, attribute values are expressed using a wide range of different formats and units of measurement.

In order to overcome the problems of synonymous attribute names and multiple templates being used for the same type of things, the DBpedia project maps Wikipedia templates as well as tables within an article to the DBpedia ontology. These mappings are specified using the DBpedia Mapping Language. The mapping language makes use of MediaWiki templates that define DBpedia ontology classes and properties as well as template/table to ontology mappings.

The following mappings map Wikipedia infoboxes and tables to this ontology:

• Infobox Mappings
• Table Mappings

Tools

• Mapping Validator. When you are editing a mapping, there is a validate button on the bottom of the page. Pressing the button validates your changes for syntactic correctness and highlights inconsistencies such as missing property definitions.
• Extraction Tester. The extraction tester tests a mapping against a set of example Wikipedia pages. This gives you direct feedback about whether a mapping works and how the resulting data will look like.
• MappingTool. The DBpedia MappingTool is a graphical user interface that supports users to create and edit mappings.
• DBpedia Mapping Language Specification (detailed)

Tutorials

The Specification of the DBpedia Mapping Language can be found here. Please find below step-by-step tutorials on:

• How to write
  • Template mappings
  • Table mappings
• Best practice mapping guide

Create new mappings

To get an idea of how mappings are written, you can look at some example from the English mappings.

To create a new mapping, type the following line into your web browser

http://mappings.dbpedia.org/index.php/Mapping_LANGUAGE:INFOBOXNAME

• replace LANGUAGE by the language code you are currently working on (for example mt for Maltese)
• replace INFOBOXNAME by the box that you want to create a mapping for (replace spaces with underscores)

e.g.

http://mappings.dbpedia.org/index.php/Mapping_mt:Infobox_album

for the Album infobox on the Maltese Wikipedia.

If there is no mapping for this box yet, you will see a page saying "There is currently no text in this page. You can search for this page title in other pages, search the related logs, or edit this page." On the top you can click on "create" and start writing the mapping.