Hi all,
more and more websites embed structured data describing for instance
products, people, organizations, places, events, resumes, and cooking
recipes into their HTML pages using markup formats such as RDFa,
Microdata and Microformats.
The Web Data Commons project extracts all Microformat, Microdata and
RDFa data from theCommon Crawl web corpus, the largest and most
up-to-data web corpus that is currently available to the public, and
provides the extracted data for download. In addition, we calculate and
publish statistics about the deployment of the different formats as well
as the vocabularies that are used together with each format.
Today, we are happy to announce the release of a new WebDataCommons dataset.
The dataset has been extracted from the latest version of the Common
Crawl. This August 2012 version of the
Common Crawl contains over 3 billion HTML pages which originate from
over 40 million websites (pay-level-domains).
Altogether we discovered structured data within 369 million HTML pages
contained in the Common Crawl corpus (12.3%). The pages containing
structured data originate from 2.29 million websites (5.65%).
Approximately 519 thousand of these websites use RDFa, while 140
thousand websites use Microdata. Microformats are used on 1.7 million
websites.
Basic statistics about the extracted dataset as well as the vocabularies
that are used together with each encoding format are found at:
http://www.webdatacommons.org/2012-08/stats/stats.html
Additional statistics that analyze top-level domain distribution and the
popularity of the websites covered by the Common Crawl, as well as the
topical domains of the embedded data are found at:
http://www.webdatacommons.org/2012-08/stats/additional_stats.html
The overall size of the August 2012 WebDataCommons dataset is 7.3
billion quads. The dataset is split into 1,416 files each having a size
of around 100 MB. In order to make it easier to find data from a
specific website or top-level-domain, we provide indexes about the
location of specific data within the files.
In order to make it easy for third parties to investigate the usage of
different vocabularies and to generate seed-lists for focused crawling
endeavors, we provide a website-class-property matrix for each format.
The matrixes indicate which vocabulary term (class/property) is used by
which website and avoid that you need to download and scan the whole
dataset to obtain this information.
The extracted dataset and website-class-property matrix can be
downloaded from:
http://www.webdatacommons.org/2012-08/stats/how_to_get_the_data.html
Lots of thanks to:
+ the Common Crawl project for providing their great web crawl and thus
enabling the Web Data Commons project.
+ the Any23 project for providing their great library of structured data
parsers.
+ the PlanetData and the LOD2 EU research projects for supporting
WebDataCommons.
Have fun with the new dataset.
Cheers,
Christian Bizer and Robert Meusel
--
Prof. Dr. Christian Bizer
Chair of Information Systems V
Web-based Systems Group
Universität Mannheim
B6, 26, Room B1.15
D-68131 Mannheim
Tel.: +49(0)621/181-2677
Fax.: +49(0)621/181-2682
Mail: [email protected]
Web: www.bizer.de