CSDGM: Content Standard for Digital Geospatial Metadata February 7, 2006 Geog 458: Map Sources and Errors

Outlines NSDI Metadata CSDGM: Overview CSDGM: Structure & syntax CSDGM: Details Creating CSDGM-compliant metadata

NSDI –Human resources, technology, standard, and policy for geospatial activity Vision of NSDI –Effective utilization of geospatial data for better understanding of environments critical to our future; data should be accessible, integrated, and managed in an effective manner Core components of NSDI –Partnership, data, framework, metadata, clearinghouse, standard

2. Role of metadata Availability Access Fitness of use Data transfer Q. Which sections should you look up in the metadata for each task?

Value of metadata It’s like a food label –what’s in it? It’s like an insurance –e.g. accuracy of data for disaster management –Enhance data value It’s investment in future –Eliminate duplication efforts –Effective data integration for effective problem-solving

CSDGM This is FGDC (U.S.) content standard for digital geospatial metadata First version: 1994 Second version: 1998 Data created with public funding should make metadata available in a way that they are compliant with CSDGM –How do you know if it’s CSDGM-compliant or not? Transition to ISO (International) standard

CSDGM It’s complex and detailed because it handles extensive spatial data set –e.g. vector file, remote sensing image, table –Same reason that SDTS is complex It’s structured because it should be read by computer (national geospatial clearinghouse) for electronic search; i.e. it should be parsable –It uses common terms (do you understand the meaning of terms used in CSDGM?) –It is hierarchically organized (does structure in metadata make sense to you?)

CSDGM: structure It uses common terms –Name of different elements are uniform It is hierarchically organized –Sections > compound elements > data elements Sections are divided into primary sections and supporting sections –Primary sections: common contents of CSDGM (e.g. identification to metadata_reference) reflecting intrinsic elements of geospatial data (e.g. georeferencing, spatial data structure) –Supporting sections: referred in multiple times by primary sections (e.g. contact, time period); thus cannot be used alone

CSDGM: syntax Understanding production rules It specifies composition rules –+ is AND, | is OR It specifies whether it’s mandatory or not –… means MANDATORY –0{…}1 means MANDATORY IF APPLICABLE What does it mean by “mandatory if applicable”? –(…) means OPTIONAL It specifies repeatability of elements –0{…}N means that this element can be repeated none to many

Production rules: examples Metadata = Identification_Information + 0{Data_Quality_Information}1 + 0{Spatial_Data_Organization_Information}1 + 0{Spatial_Reference_Information}1 + 0{Entity_and_Attribute_Information}1 + 0{Distribution_Information}n + Metadata_Reference_Information

Production rules: examples Spatial_Data_Organization_Information = 0{Indirect_Spatial_Reference}1 + 0{Direct_Spatial_Reference_Method + ( [Point_and_Vector_Object_Information | Raster_Object_Information] )}1 Do the same for Spatial_Reference Do the same for Entity_and_Attribute

CSDGM: details Draw tree-like diagrams for each section, and make sense out of them, also relate them to your previous knowledge Main components of geographic information –Identification > keywords Spatial data structure –Spatial_Data_Organization Projection, geodetic datum –Spatial_Reference > Planar > … Level of measurement –Entity_and_Attribute > … > domain values

CSDGM: details Let’s go over some unfamiliar terms Identification > Spatial Domain > –Bounding coordinates vs. Data set G-Polygon Data Quality > Attribute/Positional Accuracy > –Accuracy report vs. Quantitative Assessment –Lineage: use of abbreviation in source and process step Spatial Reference > –Local planar system –Local system –Resolution for raster vs. vector –Scale factor, false easting/northing

CSDGM: details Entity and Attribute > –Detailed description vs. overview description –Entity is table, attribute is column in the table –Domain values of attribute: {enumerated, range, codeset, unrepresentable} Distribution –Resource description

Metadata types You can create different kinds of metadata –Formal vs. informal Formal metadata: CSDGM compliant –E.g. USGS data catalog – Informal metadata: doesn’t conform –E.g. King County GIS Center: geoguide –Access from WAGDA –Minimal vs. quality You can create minimal metadata –Required: –Denver core: You can create quality metadata such that users can determine the fitness of use

Metadata formats CSDGM does not specify format, but rather content as indicated by name That’s why metadata looks different (see note section for link to different metadata) Can be in the format of html, text, xml

Creating metadata So how do I create metadata? –hard copy approach You know the title/subtitle, and what to fill in –digital copy approach Use metadata creation tool Demo: tkme from USGS How do I know this metadata conforms to FGDG Content Standard? –By understanding production rules, do this manually? –Use software (e.g. mp from USGS) EVENT1 will walk you through this….

For P2 (Lineage report) If metadata is in a good condition, use them Otherwise, talk to persons referred in metadata Look up sample metadata from USGS data catalog, and emulate them Write in two pages or so even though it will vary highly depending on data