Geospatial Data Sharing U' S' Census Bureau

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Geospatial Data SharingU. S. Census Bureau
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Topics

• Features
• Boundaries
• Addresses

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Delaware County, Ohio

• What went wrong?

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Sharing Features

• Nothing Went Wrong
• Updates were hand-drawn from updated maps
  submitted through the Boundary and Annexation
  Survey

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Sharing Features

• Penalty of going first
• Delaware County was NOT processed by Harris
• Did not have the benefit of our learning
  experience of the first 200 files

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Sharing Features

• What are we doing about this?
• Will reprocess all files that did not go through
  the rigorous Harris process
• Will process a second cycle for many local files
• Pick up new streets
• Will use Census Bureau software
• Expect to start late this summer

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Sharing Boundaries

• Delaware County, Ohio
• Boundaries that follow street centerlines
• Boundaries that follow parcel boundaries
• Edge of street right-of-ways
• Ideally need the offset of the edge from the
  street centerline

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Sharing Addresses

• Address List Improvement Act of 1994
• Established LUCA
• Congress clearly considered the confidentiality
  requirement

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Congressional Commentary

• The subcommittee is well aware of, and sensitive
  to, concerns about personal privacy. It's
  probably true that most people do not view an
  address, without related names, as private
  information. Frankly, address information is
  widely available in today's society from public
  and private sources. However, for two reasons,
  the legislation allows for only limited access to
  this most benign piece of census information.

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Congressional Commentary

• The first reason is that it may be difficult to
  communicate clearly to the American public that
  the information in question does not contain
  names or any other identifying information
  besides the physical location of a housing unit.
  Given the special trust that must exist between
  the Census Bureau and much of the American
  public, we did not want to jeopardize the
  Bureau's ability to garner cooperation in future
  censuses.

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Congressional Commentary

• The second reason for limiting access is that the
  Bureau's definition of a housing unit is
  necessarily broad and may include information not
  generally known. For example, that definition
  includes illegally occupied garages, offices,
  basement apartments, and other structures not
  normally inhabited. But while the effort to
  include every structure where a person lives is
  essential for an accurate count, the Bureau might
  inadvertently have information on its address
  lists that indicates the existence of a structure
  not properly zoned for residential dwelling. If
  the census address information were misused, an
  individual might face some adverse result.

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Discussion?
Robert LaMacchia Geography Division 301-763-2131 r
obert.a.lamacchia_at_census.gov