As we all know, DBpedia is an important dataset in Linked Data as it is not only connected to and from numerous other datasets, but it also is relied upon for useful information. However, quality problems are inherent in DBpedia be it in terms of incorrectly extracted values or datatype problems since it contains information extracted from crowd-sourced content.

However, not all the data quality problems are automatically detectable. Thus, we aim at crowd-sourcing the quality assessment of the dataset. In order to perform this assessment, we developed a tool whereby a user can evaluate a random resource by analyzing each triple individually and store the results. Here is the link to the tool: http://nl.dbpedia.org:8080/TripleCheckMate/.

If you have any questions or comments, please do not hesitate to contact us at dbpedia-data-quality@googlegroups.com.

Results

• Results : http://goo.gl/lIKK7
• Total no. of users : 58
• Total no. of distinct resources evaluated : 521
• Total no. of resources evaluated : 792
• Total no. of distinct resources without problems : 86
• Total no. of distinct resources with problems : 435
• Total no. of distinct incorrect triples : 2928
• Total no. of distinct incorrect triples in the dbprop namespace : 1745
• Total no. of inter-evaluations : 268
• No. of resources with evaluators having different opinions : 89
• Resource-based inter-rater agreement (Cohen’s Kappa) : 0.34
• Triple-based inter-rater agreement (Cohen’s Kappa) : 0.38
• No. of triples evaluated for correctness : 700
• No. of triples evaluated to be correct : 567
• No. of triples evaluated incorrectly : 133
• % of triples correctly evaluated : 81
• Average no. of problems per resource : 5.69
• Average no. of problems per resource in the dbprop namespace : 3.45
• Average no. of triples per resource : 47.19
• % of triples affected : 11.93
• % of triples affected in the dbprop namespace : 7.11

Manuscript

• Link to presentation presented at I-Semantics 2013
• Link to manuscript accepted atI-Semantics 2013