The discussions about open data sharing, interoperability,
and web services continue to build. FGDC
has published a new portal and there are new open cloud services every
day. What strikes me in these
discussions is that at some level we are still resolving data content issues.
Consider this scenario.
What if parcel data producers, mostly local governments in the U.S. and
about 6,000 different local governments, made ice cream instead of parcel
data. Almost everyone loves ice cream
but few understand the challenges of making large batches of consistent
texture, predictably flavored ice cream.
Locally made ice cream would reflect local tastes and preferences and
would evolve with the local needs and demands.
Complicating things is each state would have rules for ice
cream packaging, pricing, butter fat content, and maybe even the wafers that
could be used for making ice cream cones.
Vanilla
A consumer might think it is a simple enough question, “I
would like some vanilla ice cream.” The
ice cream maker knows there are dozens and dozens of vanilla flavors from plain
vanilla to French vanilla with variations including premium churned, fat free,
egg free, extra creamy, triple vanilla and many others. This does not include the branded names for
vanilla, which might be New York vanilla, West Coast California vanilla, and Wisconsin
true vanilla.
The mix of the base ice cream, it’s composition, fat
content, churning method, and other processing variations plus the vanilla
flavoring itself adds much variation and nuance. For example “natural flavoring” is castoreum,
which is a secretion from the castor sacs of adult North American beavers. “Real vanilla” comes from a Mexican orchid
and from subspecies in Madagascar, the West Indies and South America.
Why is it so hard to just get a national vanilla ice cream based
on the locally produced ice cream?
The local ice cream makers who understand the highly nuanced
and local needs find it hard to even find the words to explain the variations
in vanilla much less the other flavors and types of ice cream cones that are
found across the nation.
With over 6,000 producers across the country, it is not
unexpected that there are many variations and nuances. A simple request for a vanilla ice cream cone
has many options, so does requesting parcel information.
The Business Case for
a Publication Standard
The purpose of a publication standard is to describe the
business uses and needs to support defined applications. The publication standard is not a random set
of features and attributes. In the ice cream example every producer will have
variations in vanilla and a host of other flavors but it is unlikely that every
producer will have the same combination of flavors. The publication standard provides a standard
data request that each producer completes as best they can.
The publication standard educates the business user as well
as the data producer. It provides a way
for the data producer to understand why and how data are used, it limits the
number of data elements the data steward has to publish, and it makes the
highly variable and highly nuanced operational data easier for the data
requester to understand.
This point was made in the Fair and Equitable article “Sharing the Data You Have - Getting the Data
You Need”, William Craig and Nancy von Meyer, February 2009 p 9.
“Applications that need
parcel data but do not understand the finer points of parcel information cannot
distinguish between taxable value and market value, much less decipher which
value in the local data set contains the necessary value information.”
The National
Cadastral Parcel Publication Standard
The Federal Geographic Data Committee (FGDC) Cadastral
Subcommittee has a fairly in depth content standard for cadastral data. It defines the components of land
descriptions, cadastral reference systems, legal measurements, corner
monumentation, corner coordinate values, rights and interests, and restrictions
to rights and interests. The content
standard provides a checklist of information that could be included in a
cadastral data system, but it is not an implementation standard and it is not a
publication standard.
Recognizing that the path to implementation required
building a publication standard or guideline, the Subcommittee examined several
critical national business uses including hurricane and wildland fire response
and recovery, economic and mortgage monitoring and response, and energy
development and reclamation. These were
business uses that existed across the country and could be used to define a
starting national publication guideline.
Each state could add to this base guideline, but a starting base was
seen as one path to increased standard implementation.
The resulting guideline includes components for cadastral
reference information (Public land Survey System, land Grants, Subdivisions
etc.) and parcel information (real estate tax parcels and coming soon federally
managed land parcels). The publication
guideline or standard is not intended to be a burden to data stewards, it is
intended to enhance communication and encourage the use of this valuable data set in
business applications.
