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Introduction TO Metadata!. Gary Johnson Nevada Bureau of Mines & Geology. What we will talk about. What metadata are? Metadata tools (ArcView extension) www.FGDC.com. What are METADATA?. Metadata consist of information that characterizes data. .
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IntroductionTO Metadata! Gary Johnson Nevada Bureau of Mines & Geology
What we will talk about • What metadata are? • Metadata tools (ArcView extension) • www.FGDC.com
What are METADATA? Metadata consist of information that characterizes data. Metadata are used to provide documentation for data products. In essence, metadata answer: who what when where why how about every facet of the data that are being documented.
Nothing on the back of this photo,Who is in the photo? Back of photos tell whois in the photo, data of photo, where the photo was taken.
Why should I create metadata? Metadata helps publicize and support the data you or your organization have produced. Metadata explains what you have done when you are no longer with the agency. Metadata that conform to the FGDC standard are the basic product of the National Geospatial Data Clearinghouse, a distributed online catalog of digital spatial data. This clearinghouse will allow people to understand diverse data products by describing them in a way that emphasizes aspects that are common among them.
Who should create metadata? Data managers who are either technically-literate scientists or scientifically-literate computer specialists. Creating correct metadata is like library cataloging, except the creator needs to know more of the scientific information behind the data in order to properly document them. Don't assume that every -ologist or -ographer needs to be able to create proper metadata. Ensure that there is good communication between the metadata producer and the data producer; the former will have to ask questions of the latter.
How do we deal with people who complain that it's too hard? The solution in most cases is to educate the creator of the data to use an easy tool rather than to develop new tools. People often assume that data producers must generate their own metadata. Certainly they should provide informal, unstructured documentation, but they should not necessarily have to go through the rigors of fully-structured formal metadata.
The Real Question is: • If I already know what metadata are, then what next? • To learn how to compile your metadata in a standard format. • Just like a recipe. • Just like a book is catalogued in the library. • Just like a step-by-step how-to instruction manual.
Why Can’t I Just Write Readme Files? • Readme files vary in the amount and quality of information they contain. • You will be writing “readme” files, that are in a standardized format that can be searched on-line, and contain the kinds of information that we would all like to see in a “readme” file.
The “Standard” • The Federal Geographic Data Committee (FGDC) was assigned the task of developing a “standardized documentation of data” through Executive Order 12906. • What they came up with was the Content Standard for Digital Geospatial Metadata (CSDGM). • www.fgdc.gov/metadata/contstan.html
Objective of the Standard • To provide a common set of terminology and definitions for the documentation of geospatial data. • Developed from the perspective of defining information required by a prospective user.
Non Spatial Data vs. Spatial Data • Non Spatial Data (in the form of a paper map) has a legend that displays the information (the metadata) about the map. • Spatial Data has no legend, so a conscious effort is required to develop and maintain the information (metadata) that goes with the data.
Information Required by a User • Availability -- Does data exist for the geographic location I’m interested in? • Fitness For Use -- Does the data meet my specific needs? • Access -- How do I acquire a specific data set? • Transfer -- How do I process & use the data?
Organization of the Standard (derived from the FGDC’s CSGDM) • Hierarchy of compound elements and data elements (sections, sub-sections, sub-sub-sections). • Each compound element (section) is individually numbered and also contains compound elements (sub-sections) and data elements (sub-sub-sections).
Conventions for Dates (These dates use ANSI X3.30-1985: New York, American National Standards Inst.) • Calendar Dates (year, month, day) • YYYYMMDD • YYYY = year • YYYYMM = year and month • YYYYMMDD = year, month and day
Meta Data Resources: • The web has a number of resources to learn more about meta data. A couple of places to start are: • www.fgdc.gov(links to other sources, examples of meta data, meta data collection tools, and clearinghouse node). • www.lic.wisc.edu/metadata/metaprim.htm(meta data primer). • www.blm.gov/gis/metadata.html(Barney - The Meta data Hero! [a meta data tutorial]).