Some problems with standard geospatial metadata

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1 Some problems with standard geospatial metadata Simon Cox, Bruce Simons, Nick Car 12 March 2015 LAND AND WATER FLAGSHIP

2 This presentation Asks some questions Does not provide all the answers but suggests some directions Presenter name Presenter title 31 January 2012 ADD BUSINESS UNIT/FLAGSHIP NAME 2 Problems with metadata Nick Car

3 Outline ANZLIC and GeoNetwork Where did ANZLIC come from? Records Uses of metadata UML vs XML RDF RDF vocabularies Presenter name Presenter title 31 January 2012 ADD BUSINESS UNIT/FLAGSHIP NAME 3 Problems with metadata Nick Car

4 ANZLIC Metadata Presenter name Presenter title 31 January 2012 ADD BUSINESS UNIT/FLAGSHIP NAME 4 Problems with metadata Nick Car

5 Where did ANZLIC come from? ANZLIC a profile of ISO 19115:2003 5

6 Where did ANZLIC come from? ANZLIC a profile of ISO 19115:2003 ISO designed by a committee 6

7 Where did ANZLIC come from? ANZLIC a profile of ISO 19115:2003 ISO designed by a committee (horse designed by committee = camel) 7

8 Where did ANZLIC come from? ANZLIC a profile of ISO 19115:2003 ISO designed by a committee US FGDC metadata a strong precedent requirements collected in the 1990s image and map librarians (horse designed by committee = camel) 8

9 Where did ANZLIC come from? ANZLIC a profile of ISO 19115:2003 ISO designed by a committee US FGDC metadata a strong precedent requirements collected in the 1990s image and map librarians (horse designed by committee = camel) > dawn of the internet, dataset == file > 10,000s datasets in standard series, metadata == digital index cards 9

10 Problem #1: Data Datasets? When cataloguing books, maps, images, even files, the card-index metaphor is OK A discrete record for each item of data Now we expect to access data at a variety of granularities, the dataset/metadata record paradigm no longer applies It is a sea of data, and should be matched by a sea of metadata (maybe in the same place) 10 Problems with metadata Nick Car

11 Breaking it down Structural decomposition Functional decomposition 11 Problems with metadata Nick Car Lawrence, Lowry, Miller, Snaith & Woolf, Information in environmental data grids. Phil. Trans. A, 2009

12 Problem #2: One record can t serve all purposes But one record is all you got! 12 Problems with metadata Nick Car

13 ISO metadata was formalized as UML classes 13 Problems with metadata Nick Car

14 GeoNetwork stores metadata as XML documents in a text database (Lucene) 14 Problems with metadata Nick Car

15 Problem #3: Documents package text, not objects Instances of UML classes = Objects XML document = serialization for transport Treating the XML document as canonical makes a basic category error: XML validation quality control if you only intend to manage it as text, why bother with a UML analysis? For object-oriented behavior, the serialized form must be unmarshalled for processing 15 Problems with metadata Nick Car

16 Metadata creation 16 Problems with metadata Nick Car

17 Problem #4: Index cards are not infrastructure Metadata-entry paradigm encourages record counting as a KPI Surely there are better measures of usefulness? How can we know, if it is not part of a joined-up architecture 17 Problems with metadata Nick Car

18 What does everyone else do? 1. Specialist systems for specialized communities Is spatial special? Do we want our spatial data in the mainstream? 2. Don t bother with metadata, just index the content The original strategy of the search engines Google Knowledge Graph now works with entities, not text (shame the entities don t have persistent URIs ) 3. Metadata annotations schema.org semantic-web-lite 4. What about the Data Repositories? 18 Problems with metadata Nick Car

19 Research Data Repositories Still a lot of variation RIF-CS MARC Dublin Core Data Catalog Vocabulary (DCAT) 19 Problems with metadata Nick Car

20 Research Data Repositories Still a lot of variation RIF-CS MARC Dublin Core Data Catalog Vocabulary (DCAT) 20 Problems with metadata Nick Car

21 Research Data Repositories Still a lot of variation RIF-CS MARC Dublin Core Data Catalog Vocabulary (DCAT) RDF vocabularies? DC, DCAT FOAF, PROV-O, VoID, SKOS, ADMS, LOCN 21 Problems with metadata Nick Car

22 INSPIRE profile of DCAT-AP 22 Problems with metadata Nick Car

23 INSPIRE metadata record as RDF 23 Problems with metadata Nick Car

24 RDF benefits Standard vocabularies used in the broader community Intrinsically object/resource oriented URIs for keys - linked data Open world missing information doesn t make it invalid No intrinsic granularity 24 Problems with metadata Nick Car

25 Summary ANZLIC + GeoNetwork: Record-oriented metadata doesn t match granularity of data Each record must serve multiple functions Object oriented design, but serialization-oriented processing Incentive to create records, not architecture Not aligned with anyone else s metadata RDF?: Graph of metadata to match graph of data Targeted metadata subsets can be constructed using SPARQL Intrinsically resource-oriented Part of web of Linked Data Standard RDF vocabularies 25 Problems with metadata Nick Car

26 Thank you Land and Water Flagship Nick Car Research Engineer t e nicholas.car@csiro.au Land and Water Flagship Simon Cox Research Scientist t e simon.cox@csiro.au w people.csiro.au/c/s/simon-cox LAND AND WATER FLAGSHIP

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