Metadata Development and Maintenance

1. Metadata Development and Maintenance Belize National Spatial Data Infrastructure July 29th – 30th 2009

2. This Discussion • What is metadata • What is its value • How is it composed • How is it maintained • What are the issues

3. What is "Metadata"? • "metadata" is formal data documentation and is critical to data discovery • A metadata record is a file of information, usually presented as an XML document, which captures the basic characteristics of a data or information resource. • It represents the who, what, when, where, why and how of the resource.

4. What can we tell about these pictures without some documentation on where it was taken, who took it, on what occasion, when and with what equipment?

5. The value of background information • This label with its mandatory and voluntary components, tells the consumer everything they need to know to make an informed decision about the food's ingredients and nutritional content.

6. Metadata Standards

7. The Major uses of Metadata • Organize and maintain an organization's internal investment in spatial data, • Provide information about an organization's data holdings to data catalogues, clearinghouses, and portals, and • Provide information to process and interpret data received through a transfer from an external source.

8. What is Included in a Metadata Record? • A complete metadata record typically includes: • Core library catalog elements such as Title, Abstract, and Publication Data; • Geographic elements such as Geographic Extent and Projection Information; and • Database elements such as Attribute Label Definitions and Attribute Domain Values.

9. Identification Information • Title • geographic area covered • currentness, and • rules for acquiring or using the data.

10. Data Quality Information • Positional and attribute accuracy, completeness, • Consistency, • Sources of information, and • Methods used to produce the data.

11. Spatial Data Organization Information • mechanism used to represent spatial information in the data set. • Method used to represent spatial positions directly (such as raster or vector) and indirectly (such as street addresses or county codes) and • The number of spatial objects in the data set.

12. Spatial Reference Information • Description of the reference frame for, and means of encoding, coordinates in the data set. • The name of and parameters for map projections or grid coordinate systems, horizontal and vertical datums, and • The coordinate system resolution.

13. Entity and Attribute Information • Information about the content of the data set • Entity types and their attributes and the domains from which attribute values may be assigned. • The names and definitions of features, attributes, and attribute values.

14. Distribution Information • Information about obtaining the data set. • Contact information for the distributor, available formats, • information abouthow to obtain data sets online or on physical media (such as cartridge tape or CD-ROM), and • fees for the data.

15. Data Maintenance and Update • As the number of data sets within a collection grows and storage space is reduced, it can be difficult to determine those data that should be maintained and those that should be disposed of.

16. Value of Metadata • Facilitates data maintenance • Facilitate data discovery • Enables reuse of data • Informs potential data users of inappropriate uses of a dataset

17. Data Maintenance and Update • Candidates for data update, archive, or removal can be identified using temporal and data processing metadata elements.

18. Data Discovery and Reuse • Metadata is the fuel for data discovery. • Use of data portals and other forms of online data catalogs, • users can post documentation about their data holdings and those in need, can query the Internet for available data using parameters of geography, time, and theme.

19. Data Discovery and Reuse • Once potential data resources are discovered, users can access the metadata to learn more about the data • Content, • Availability, and limitation and • Better assess the fitness of use of the data to meet their specific need.

20. Data Accountability • The practice of writing metadata is an exercise in data comprehension and accountability. • The metadata creator must be willing to associate themselves with the metadata content. • The individual documenting the data set must fully understand error analyses and data quality assessment, the character and limitations of the source data, and the definitions and domains of all attributes..

21. Data Liability • A well-written metadata record is an opportunity to state what the data are not. • Metadata can prove most useful in advising others in the appropriate and misappropriate application of the data. • An explicit purpose statement can clearly outline special project conditions and requirements that may affect the applicability of the data to other projects. • Use constraint statements can be crafted to express scale, geographic, or temporal limitations to the data. Liability statements should be written by • legal staff to ensure that the legal requirements for use of the data are fully outlined. In general, it is far better to publish your data set limitations within your metadata than to later attempt to generate them in response to an inquiry or lawsuit.

22. Data Liability • Use constraint statements can be crafted to express scale, geographic, or temporal limitations to the data. • Liability statements should be written by legal staff to ensure that the legal requirements for use of the data are fully outlined. • In general, it is far better to publish your data set limitations within your metadata than to later attempt to generate them in response to an inquiry or lawsuit.