Comments on: LOD cloud shows surprisingly lumpy structure http://blog.larkc.eu/?p=1941 Wed, 08 Sep 2010 22:00:41 +0000 http://wordpress.org/?v=2.3.3 By: Tom Morris http://blog.larkc.eu/?p=1941#comment-120421 Tom Morris Mon, 17 May 2010 20:36:05 +0000 http://blog.larkc.eu/?p=1941#comment-120421 Any chance of scalable version (SVG?) of these graphics? The Gephi version is better, but some sections are still too dense to read labels. The assumption that starting data table is accurate may not be valid. For the spot checking I did, it was missing significant chunks of stuff. For example, Freebase and DBpedia are basically fully bidrectionally connected for the things they have in common (80%+ of DBpedia?), but this isn't represented at all. Freebase also links to MusicBrainz and a number of other data sources. One other thing worth noting is that it appears the diameter of the nodes now represents in-degree rather than number of triples stored. Any chance of scalable version (SVG?) of these graphics? The Gephi version is better, but some sections are still too dense to read labels.

The assumption that starting data table is accurate may not be valid. For the spot checking I did, it was missing significant chunks of stuff. For example, Freebase and DBpedia are basically fully bidrectionally connected for the things they have in common (80%+ of DBpedia?), but this isn’t represented at all. Freebase also links to MusicBrainz and a number of other data sources.

One other thing worth noting is that it appears the diameter of the nodes now represents in-degree rather than number of triples stored.

]]> By: Jose Manuel Gomez-Perez http://blog.larkc.eu/?p=1941#comment-120281 Jose Manuel Gomez-Perez Mon, 17 May 2010 13:10:30 +0000 http://blog.larkc.eu/?p=1941#comment-120281 Nice work. IMHO, this kind of visualizations can provide useful insight in order to improve LOD from an architectural viewpoint so to say, e.g. to detect scalability issues, maximize domain coverage, support detection of redundancies, etc. On the other hand, something that can be drawn from this particular work is a notion of the domains where LOD is having a greater impact currently: Bio and Biblio, complemented with general purpose knowledge from the DBPedia cluster. However, this can be seen the other way around: probably these domains are the best represented ones because their respetive communities have traditionally had a deeper involvement in LOD. Nice work. IMHO, this kind of visualizations can provide useful insight in order to improve LOD from an architectural viewpoint so to say, e.g. to detect scalability issues, maximize domain coverage, support detection of redundancies, etc.

On the other hand, something that can be drawn from this particular work is a notion of the domains where LOD is having a greater impact currently: Bio and Biblio, complemented with general purpose knowledge from the DBPedia cluster. However, this can be seen the other way around: probably these domains are the best represented ones because their respetive communities have traditionally had a deeper involvement in LOD.

]]> By: Kingsley Idehen http://blog.larkc.eu/?p=1941#comment-109661 Kingsley Idehen Sun, 28 Mar 2010 22:10:12 +0000 http://blog.larkc.eu/?p=1941#comment-109661 Belated comments. Nice post. The Linked Open Data realm is really a lumpy galaxy. It certainly isn't a DBpedia based Solar System :-) Links: 1. http://bit.ly/90tUKJ -- old post titled State of the Linked Data Web. Belated comments.

Nice post.

The Linked Open Data realm is really a lumpy galaxy. It certainly isn’t a DBpedia based Solar System :-)

Links:

1. http://bit.ly/90tUKJ — old post titled State of the Linked Data Web.

]]> By: Hugh Glaser http://blog.larkc.eu/?p=1941#comment-105071 Hugh Glaser Fri, 12 Mar 2010 10:33:27 +0000 http://blog.larkc.eu/?p=1941#comment-105071 Nice work indeed. Hopefully Anja (and others) won't have to spend their time doing the cloud by hand any more - thanks for the efforts over the years! Looks like it is showing how disconnected RKB is from the rest of the world. However, it isn't actually quite that bad, you will be pleased to hear. There are quite a lot of point-wise links from different RKB stores to dbpedia and others. It is just that I haven't found the time to put in small numbers of links (and didn't want to make the table overloaded with RKB stuff). And actually there is a whole unlocode RKB site missing (with links to geonames and datagovuk I think), and probably some others. A great thing about these pictures is that it is now easy for me to see such things, and dataset publishers will feel encouraged to keep the data up to date. Nice work indeed.
Hopefully Anja (and others) won’t have to spend their time doing the cloud by hand any more - thanks for the efforts over the years!

Looks like it is showing how disconnected RKB is from the rest of the world.

However, it isn’t actually quite that bad, you will be pleased to hear. There are quite a lot of point-wise links from different RKB stores to dbpedia and others. It is just that I haven’t found the time to put in small numbers of links (and didn’t want to make the table overloaded with RKB stuff).
And actually there is a whole unlocode RKB site missing (with links to geonames and datagovuk I think), and probably some others.

A great thing about these pictures is that it is now easy for me to see such things, and dataset publishers will feel encouraged to keep the data up to date.

]]> By: Pieter De Leenheer http://blog.larkc.eu/?p=1941#comment-104891 Pieter De Leenheer Thu, 11 Mar 2010 16:23:37 +0000 http://blog.larkc.eu/?p=1941#comment-104891 the formation of criticial hubs is typical to scale-free networks. Amazing that knowledge networks organise according to the same pattern as social networks. I would be interesting to compare both networks here and make correlations. This would indeed lead to the conclusion is the main champion driving discussions within the initiative. Where is the SIOC graph :-) ? the formation of criticial hubs is typical to scale-free networks. Amazing that knowledge networks organise according to the same pattern as social networks. I would be interesting to compare both networks here and make correlations. This would indeed lead to the conclusion is the main champion driving discussions within the initiative. Where is the SIOC graph :-) ?

]]> By: Joshua Shinavier http://blog.larkc.eu/?p=1941#comment-104571 Joshua Shinavier Wed, 10 Mar 2010 20:56:11 +0000 http://blog.larkc.eu/?p=1941#comment-104571 Also check out Marko Rodriguez's analysis from March 2009: http://arxiv.org/abs/0903.0194 This paper likewise describes several distinct clusters of linkage. Some other observations: 1) the LOD graph is not strongly connected 2) a diameter of 8 is large given relatively small size of the cloud 3) data sets in the cloud have nearly identical incoming and outgoing link patterns (which indicates that the majority of links are reciprocal owl:sameAs) Also check out Marko Rodriguez’s analysis from March 2009: http://arxiv.org/abs/0903.0194
This paper likewise describes several distinct clusters of linkage. Some other observations:
1) the LOD graph is not strongly connected
2) a diameter of 8 is large given relatively small size of the cloud
3) data sets in the cloud have nearly identical incoming and outgoing link patterns (which indicates that the majority of links are reciprocal owl:sameAs)

]]> By: Dan Brickley http://blog.larkc.eu/?p=1941#comment-104561 Dan Brickley Wed, 10 Mar 2010 20:12:02 +0000 http://blog.larkc.eu/?p=1941#comment-104561 Re the 'two orgs' vulnerability; since this is all open shared data, you would hope that the data would still be useful and used even if the original source drops off the 'net. Of course RDF and the Linked Data model especially put particular weight on domain-name based HTTP URIs. So I guess we should take care to pick 'em carefully, cos changing them afterwards is going to be tricky... Re the ‘two orgs’ vulnerability; since this is all open shared data, you would hope that the data would still be useful and used even if the original source drops off the ‘net. Of course RDF and the Linked Data model especially put particular weight on domain-name based HTTP URIs. So I guess we should take care to pick ‘em carefully, cos changing them afterwards is going to be tricky…

]]> By: PaulGroth http://blog.larkc.eu/?p=1941#comment-104501 PaulGroth Wed, 10 Mar 2010 16:39:43 +0000 http://blog.larkc.eu/?p=1941#comment-104501 Interesting observation by @Richard, two of the major clusters of the LOD (scholarly data and bio data ) are run by two organizations. So if Southampton and Bio2rdf collapse these chunks die. Would nice to see more organizations hosting or make sure that these organizations have enough support so that they can ensure uptime. Interesting observation by @Richard, two of the major clusters of the LOD (scholarly data and bio data ) are run by two organizations. So if Southampton and Bio2rdf collapse these chunks die. Would nice to see more organizations hosting or make sure that these organizations have enough support so that they can ensure uptime.

]]> By: Pieter De Leenheer http://blog.larkc.eu/?p=1941#comment-104491 Pieter De Leenheer Wed, 10 Mar 2010 16:33:06 +0000 http://blog.larkc.eu/?p=1941#comment-104491 Great to see the network effect here ! Great to see the network effect here !

]]> By: FrankVanHarmelen http://blog.larkc.eu/?p=1941#comment-104481 FrankVanHarmelen Wed, 10 Mar 2010 16:24:30 +0000 http://blog.larkc.eu/?p=1941#comment-104481 Christophe Gueret's script for generating the .net file is at http://bit.ly/aho1Ut Christophe Gueret’s script for generating the .net file is at http://bit.ly/aho1Ut

]]>