I take no pleasure in being right.
Earlier this week, I speculated that the Open Knowledge Graph might be scaled back or shut down. This morning, I awoke to a post by the project's creators, Thomas Steiner and Stefan Mirea announcing the closing of the OKG.
The Open Knowledge Graph was, according to its creators, "an attempt to [open] up the Google Knowledge Graph by means of crowdsourcing;" a project that used the power of the crowd to create an API for Google's Knowledge Graph. People were invited to install a browser plug-in that, as they used Google Search, would scrape the Knowledge Graph and store discovered facts in a publicly available resource (query-able through a SPARQL endpoint). With more than 500 million objects in the Knowledge Graph, representing 3.5 billion facts and relationships, the most practicable method for crawling may well be the crowd-sourced approach, and the OKG set out to test that theory.
Why was it shut down?
The official announcement includes the following statement from Jack Menzel, Product Management Director at Google:
"We try to make data as accessible as possible to people around the world, which is why we put as much data as as we can in Freebase. However there are a few reasons we can't participate in your project.
First, the reason we can't put all the data we have into Freebase is that we've acquired it from other sources who have not granted us the rights to redistribute. Much of the local and books data, for example, was given to us with terms that we would not immediately syndicate or provide it to others for free.
Other pieces of data are used, but only with attribution. For example, some data, like images, we feel comfortable using only in the context of search (as it is a preview of content that people will be finding with that search) and some data like statistics from the World Bank should only be shown with proper attribution.
With regards to automatic access to extract the ranking of the content: we block this kind of access to Google because our ranking is the proprietary core of what Google provides whenever you use search—users should access Google via the interfaces we provide."
How successful was the OpenKnowledgeGraph project?
In its short, 26-day life (OKG launched on August 11, 2012), the project generated an impressive 2,850,510 RDF triples. We expect to hear more in November when the project creators present their paper, "SEKI@home, or Crowdsourcing an Open Knowledge Graph" was accepted for publication at the 1st International Workshop on Knowledge Extraction and Consolidation from Social Media (KECSM2012), collocated with the 11th International Semantic Web Conference (ISWC2012). The authors also suggest that, although currently inactive, the Chrome plugin may have a future, "We will keep online the SEKI@home Chrome extension for future use (so if you have it installed, please do not uninstall it quite yet)."
From A-to-Zelazny the OpenKnowledgeGraph was an interesting proof of concept that I hope will resurface sooner rather than later. For now, I'll keep the plugin installed.