Topics in Module 2:

• Assumptions Used in Developing the Standard
• History and Background Leading to the Standard
• Participants in the Development of the Standard
• Timeline
• Process Used to Develop the Standard
• User Levels/Types of Users
• Description of the Standard
• Links and References to Information on Data Modeling

Assumptions Used in Developing the Standard

1. The Standard contains sufficient information to automate existing land records information. That is, the entities, attributes, and processes reflect information contained in typical land records documents and on cadastral plats of survey.
2. The Standard intends to reflect data contained in local, state, and federal government systems.
3. The Standard supports the needs of local users as well as federal applications.
4. The Standard does not judge or qualify information in the public record. The Standard is a repository for information recorded on plats and in documents related to land ownership that can be applied to analyze public record quality.
5. The Standard is document driven. All information in data systems relate to a written record. The term document applies to maps, graphics, images, words, and any other written material. The document driven requirement is met through the Federal Geographic Data Committee's Content Standard for Digital Geospatial Metadata.
6. The Standard covers the information contained within documents, not the document management system itself.
7. The Standard is measurement based. This means the Standard contains the information necessary to automate and store record measurements of land ownership and to provide the pathway for measurements contributed to information generated from public records.
8. Coordinate values that are not already in the public record can be computed from information contained in this Standard. Information about judgements made in selecting pertinent data for coordinate computation are also captured in the Standard.
9. The Standard is technology independent. A basic level of database, information systems, and computational capabilities are required to implement the Standard. Technology independent means that no specific brand names or products are implied or intended in the Standard.

History and Background Leading to the Standard

On October 19, 1990, the Office of Management and Budget Circular No. A-16 called for "...facilitation of exchange of information and transfer of data; the establishment and implementation of STANDARDS for quality, content, and transferability; and the coordination of the collection of spatial data to minimize duplication of effort where practicable and economical."

Circular A-16 also specified the following purposes and intents:

"A major objective of this Circular is the eventual development of a national digital spatial information resource, with the involvement of Federal, State, and local governments, and the private sector."

"...enable sharing and efficient transfer of spatial data between producers and users."

"...build information partnerships among government institutions and the public and private sectors... "

"...avoiding wasteful duplication of effort and ensuring effective and economical management of information resources..."

"...each coordinating Department will arrange...for exchange of information...concerning technological developments."

"An interagency coordinating committee will be established ...called the Federal Geographic Data Committee..." (FGDC) "The objective of this interagency coordinating committee is to promote the coordinated development, use, sharing, and dissemination of surveying, mapping, and related spatial data."

"...the development and implementation of standards, exchange formats, specifications, procedures, and guidelines;"

On April 13, 1994, Executive Order 12906, mandated the following:

"The FGDC shall develop standards for implementing the NSDI, in consultation and cooperation with State, local, and tribal governments, the private and academic sectors, and, to the extent feasible, the international community..."

"...standards shall be submitted to the Department of Commerce for consideration as Federal Information Processing Standards."

"Federal agencies collecting or producing geospatial data, either directly or indirectly (e.g. through grants, partnerships, or contracts with other entities), shall ensure, prior to obligating funds for such activities, that data will be collected in a manner that meets all relevant standards adopted through the FGDC process."

Participants in the Development of the Standard

• Linda Brooks, BLM
• Patrick Carroll, FWS
• Michael Domaratz, FGDC Exec. Sec.
• Jeff Egan, Tri-Services Technology Center
• Theresa Ely, BLM
• John Guthrie, USGS NMD
• Paula Langley, BLM
• Steve McDevitt, US Army Corps of Engineers
• Dennis Moonier, USFS
• Yvonne Morehouse, MMS
• David Moyer, NGS
• Richard Naito, MMS
• Denise Perreca, USGS NMD
• Thomas Phelps, Naval Facilities Engineering
• Louise Precosky, BLM
• Randy Roberts, Corps of Engineers
• Paul Rogers, MMS
• Gary Speight, BLM
• Lee Thormahlen, MMS
• Margaret Watry, USFS
• Assisted by Nancy von Meyer, Fairview Industries
• John Moeller, BLM, Chairman Cadastral Subcommittee

Timeline

The TAG met ten times from September 1993 to September 1994, held several open meetings and forums, and also met in sub-groups to address specific issues.

In March 1994, Version 1 of the Cadastral Data Content Standard was released for comment and review. Comments were then summarized, discussed, and answered.

A new version of the Standard was submitted to the FGDC in September of 1994. This version was released for public comment in a review period from January 1995 - May 31, 1995. Comments from this period were reviewed and incorporated into the Standard.

The Cadastral Data Content Standard was approved in 1996.

Process Used to Develop the Standard

The TAG reviewed OMB Circular A-16, the Vice President's national performance review goals and requirements, the need for improved customer service by the Federal Government, goals of the FGDC, and requirements for full participation in National Spatial Data Inventory (NSDI) according to Executive Order 12906. All this was used to form the scope, mission, and goals for development of the Standard, thus arriving at the following requirements:

• to support Federal policies related to land management and land use
• to contribute to the information requirements for sustained development at all levels of government
• and to provide sufficient information to ensure continued secure land title and land right holdings for all citizens of the U.S.A.

Work Plan. A Work Plan was developed from the results of the initial study. The initial study determined four standards were needed: Content Standard, Collection Standard, Clearinghouse Metadata Profile, and Transfer Standard. The Content Standard is approved and published. It was decided the Collection Standard will not be created. The Clearinghouse Metadata Profile is waiting on FGDC definition, and the Transfer Standard is in progress. For further information on the progress of these and other standards, refer to the Status of FGDC Standards.

Meeting Structure and Organization. Each team member assembled data, definitions, codes and other information from their respective agency. The TAG meetings brought this information together to form an optimum solution. The team summarized notes, revised data models and processes, and modified definitions.

Review Sessions. Draft versions of the Standard were circulated among Federal Agencies and interested parties outside the Federal government. Articles were published in land professional and GIS association newsletters describing the Standard and asking for input. Open forums were held at national and regional conferences. Seminars and discussions included representatives from county government, data conversion businesses, state agencies, and local agencies. Results of these review sessions were incorporated in the Standard.

Standards Components. The TAG identified the four components of the Standards to be developed, as mentioned above: Content Standard, Collection Standard, Clearinghouse Metadata Profile, and Transfer Standard. (This course pertains to the Content Standard only.)

Existing Standards. The TAG integrated the Cadastral Data Content Standard with other existing standards as much as possible. Standards reviewed included: Federal Information Processing Standards Publications; the FGDC Content Standard for Digital Geospatial Metadata; USGS and BLM Public Land Survey System meridian definitions; and other local and state government standards.

Integration with Federal Geographic Data Committee Subcommittees. The TAG identified entities such as geopolitical boundaries, addresses, agency names, and private organizations which may overlap entities defined by other FGDC Subcommittees when those Subcommittees define their entities and attributes.

User Levels/Types of Users

1. Presentation use of cadastral data is for displaying information.

2. Analysis. This level of use is for GIS analysis.

3. Transaction. The transaction level of use of cadastral data pertains to property transactions.

To investigate these concepts in more detail, and look at examples, see training Module 3.

Description of the Standard

• defines the attributes or elements that are in land ownership related documents
• standardizes domains, which are allowable entries, for many elements
• provides an interagency definition for each element.

The Standard is a repository. It does not limit or filter the information that can be included. Information is included as it appears in the public record.

The Standard contains rules for relationships between entities and attributes.

The Standard remains open to change, and is intended to meet the needs of all levels of organizations and uses.

Further information and discussion on topics such as elements, entities, and attributes can be found in the training Module Four section on Understanding the Diagram Conventions.

Links and References to Information on Data Modeling

• Applied Information Science
• There is a commercial data modeling product from agpw, inc., known as Data Master. Though we have not reviewed it and cannot endorse the product, it may be worth investigating.

Bruce, T.A., Designing Quality Databases with IDEF1X Information Models, Dorset House, 1992.

Chen, P.P.S., "The Entity-Relationship Model -- toward a unified view of data". ACM Transactions on Database Systems 1, 1, March 1976.

Jackson, Michael A., System Development. Prentice Hall International, Englewood Cliffs, New Jersey, 1983.

Federal Information Processing Standards Publication 184, the Standard for Integration Definition for Information Modeling, U.S. Department of Commerce, Technology Administration, National Institute of Standards and Technology, December 1993.

One of the best short summaries of Bachman and Chen data modeling methods which we have found is in McDonnell Douglas' ProKit WORKBENCH Application Manual, Chapter 8, Data Modeler. This is a proprietary software documentation manual, so as far as we know it is not a book available for purchase. Contact McDonnell Douglas (1-800-225-7760) if you are interested.

Surprisingly, there is virtually no widely accessible published information on the Charles Bachman method of data modeling. A search on the subject of Bachman data modeling brought up the following articles:

• Bachman Information Systems Data Base Management No. 6, The Entity Relationship Approach to Logical Data Base Design. Q.E.D. Monograph Series (Wellesley: Q.E.D. Information Science, Inc. 1977)
• C.W. Bachman "Data Structure Diagrams" Journal of ACM SIGBDP Vol 1 No 2 (March 1969) pages 4-10.
• McFadden & Hoffer _Database Management_, 3e, Benjamin Cummings, 1991, ISBN 0-8053-6040-9 or Date _An Introduction to Database Systems_, Volume 1, 5e, Addison Wesley, 1990, ISBN 0-201-51381-1.
• Charles W. Bachman: The Role Data Model Approach to Data Structures. 1-18, published in S. M. Deen, P. Hammersley: Proceedings International Conference on Data Bases, University of Aberdeen, July 1980. Heyden & Son, 1980, ISBN 0-85501-495-4.

This ends Course Module 2. Use the links below to return to the top of this page, or to go on to Module 3, or any of the other Modules.

Links to the Course Modules: [Quick Reference] [Introduction] [Module 1: Purpose and Benefits of the Cadastral Data Content Standard] [Module 2: How the Standard Was Developed] [Module 3: Other Standards and Related Activities] [Module 4: Data Modeling Techniques, Rules and Diagram Conventions] [Module 5: Crosswalks, Translations, and Examples] [Module 6: Understanding Compliance with the Standard] [Module 7: Maintenance of the Standard] [Module 8: User and Technical Support] [County Recorder Module] [GIS Specialist Module] [Surveyor Module] [Glossary]