a conceptual model for placename geography in gis scott morehouse director, software development...
TRANSCRIPT
A Conceptual Model for Placename
Geography in GIS
Scott MorehouseDirector, Software Development
ESRI
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Geography of Places - A Trivial problem?
“Oh yeah, add something for variant spellings… and maybe a time stamp… and I guess we need a provenance… and standard word lists… and...
Philosophy of Geography to the rescue!?
Lat Lon Name- - -- - -- - -
Select Lat, Lon from Gazetteer where Name = ‘Los Angeles’
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What is a Place? What are Place names?
Places are not simply “things in space”, they are a part of space itself. Places are not features! There are an infinite number of places in space and there are many
ways to define places in space.
Places can be the space occupied by a named thing (“Lake Ontario”)
Places can be described as well as named. (“north shore of Long Island”)
Places exist in a context of language, time, geographic hirerarchy, and descriptive syntax. The same place name can mean different locations, depending on context.
Places can have fuzzy location (“Rocky Mountains”)
Places can have fuzzy names or descriptions (“White House” = “1600 Pennsylvania Avenue” = “1600 Penn. Ave”)
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Examples of Places
Rocky Mountain National Park 42
813 Clifton Av., Pittsburgh, PA Luck Star Mine near Blythe
Los Angeles, California Mississippi River
90210 Mississippi River Basin
64º 23’ 18º 52’ Speke Expedition, Day 23
187,322 E 23,543 N Patagonia
North Fork, Kern River (909)555-1212
Bellows Falls I-10 233.5
T14N R6W S4 NW 1/4 Hollywood & Vine
Potomac River, Chain Bridge + 3.2 Are these names? Or descriptions? How much can a poor gazetteer do?
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A Framework for Locating Places
Address Location
Parse
Standardize
Score & Choose
Search for matches and construct
candidates
Component, component,...Candidate
List
Database of named things,relationships, and standard
address components
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Interesting Questions
How much parsing, candidate finding, and scoring is the responsibility of the gazetteer? Is the gazetteer simply the database of standard name components?
Are gazetteer standards intended for developers of location services or for direct use by end users?
How much context for names is necessary?
Each style of address has an implied context - postal geography, administrative geography, land survey, etc.
How much context should be explicitly represented in the database vs. discovered “on the fly”? Should we attempt to model things like “SFO is in San Francisco is in Bay Area is near the Delta”? Or use generalized spatial search?
Is a “one size fits all” standard applicable or are there different standards for different types of place description?