Agreed these are thematic cooridinates. But like all things digital and spatial, many users outside the library will presume the coordinates are accurate as well as official and they will be constrused to mean the coordinates had some legal definition of borders. I have seen it happen on many occassions especially with regard to scale. The perception of many users is that just because it is digital it is positionally accurate at any scale. If GPS is going to be used I would like to develop an educational/certification program about the tool and associated errors for those catalogers who are going to use it. We should also incorporate a statement about the unit used, the measurement parameters, and potential errors. GNIS does have a database of historical names. As to naming places, a name implies a locality and not an exact position as do coordinates. I live in a Town that people often say they are from, when in fact the name of the Town is often used by them to describe a 67 square mile area around the Town. So I think naming a place is different from collecting the coordinates to represent it and often both are poorly chosen.

You might want to consider a statement such as "Coordinates are provided for general location information only."

I'll be away for the next couple of weeks. It's been a great discussion. I hope I have added a different perspective.

Thanks Joe

-----Original Message----- From: Subject Coordinates Discussion List on behalf of Colleen Cahill Sent: Thu 7/13/2006 7:53 AM To: [log in to unmask] Subject: Re: [SUBCOOR] The proposal passed MARBI! Paige Andrew wrote:

As to the accuracy of a set of coordinates, of course that depends on the source and I believe (Colleen, help me out here) that we are going to rely on data primarily from trusted sources such as GNIS and GEOnet, but also are gathering datasets from ESRI and other like institutions.

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Paige is correct that coordinate data will need to come from trusted sources, but there are some that might be constrained from offering their data. Since the Broad of Geographic Names is the body that establishs the US officially recognized name for foreign places, they would hestitate to give bounding box coordinates as this could be constrused to mean the coordinates had some legal US definition of borders. It would also be possible for coordinates to be added by the cataloger who is creating the authority record an in some cases, this might be the best source for that data, as they could have access to local information. If they are trusted to establish the name, why not the coordinates, if easily found?

One thing to keep in mind is these are thematic coordinates, not legally bindings ones. Like any authority data, they can be updated and corrected as needed. Since their primary purpose is for subject searching, the question of who is an authority needs to be tempered with that. And for historical data, we are likely to have to look beyond GNIS, focuses on current coordinate information.

Colleen Colleen R. Cahill | [log in to unmask] Digital Production Coordinator | (202)707-8540 & Recommending Officer for | FAX (202)707-8531 Science Fiction & Fantasy | Library of Congress These opinions are mine, Mine, Mine! | Washington, DC 20540-4652