A meaningful ontology
of location
From (37.852,-122.252) to homeand back again

Re-iteration of the concept: the dwindling of devices that don’t have geolocation and how thenumbers aren’t very useful to me.
Agenda:Look at existing work at different levels of “meaning”.
Describe some of the uses that will drive how we use these different concepts.

Neogeography
Personal data

Military and political

Light-weight tools

Traditional GIS tools

Good enough

PreciseNeogeographers as opposed to, jokingly, paleogeographers. Differences are not well-defined(besides age), but:
I’m coming from the Neogeography side, both since that’s my background and since I’m
focused on the personal data aspect, but I’ll try to integrate some “paleo” concepts.

The current state of locationon the Web: lat/lon
W3C Geolocation
GeoRSS
geo: URI scheme
Geo microformat
iPhone CoreLocation
Win7 Location Platform

The current state of locationon the Web: lat/lon
Why?
Unambiguous
Convenient for data storage
No interoperability problems
Obvious how to use it

Not actually unambiguous (World Geodetic System 1984) but in mailing list discussions, oftenneogeographers don’t even realize it could be ambiguous.

Are coordinates meaningful?
Personal ontology
Geographic ontology

At homeIn Berkeley, in California,
near San Francisco

Named location /civic address

3141 College Ave, Berkeley

Latitude/longitude(37.852,-122.252)

Are they meaningful? Different levels of meaning which I’ll roughly sketch out here.
But keep in mind that this ordering of meaning bottom to top might be reversed dependingon your point of view.

Gazetteers“Vocabulary control is the sine qua non of
information organization.” – Elaine Svenonius
United Nations Conferences on the Standardization of
Geographical Names (UNCSGN)
ISO 3166
GeoNames
Geocoding & reverse-geocoding

We talked last week about these large books of geographic names for atlases along withcoordinates.
Sometimes we just need to specify the spelling (vocabulary control): a big issue in thedeveloping world like Thailand.
A more recently developed tool is GeoNames: an open gazetteer with millions of names.
And Yahoo!/Google/etc. provide Geocoding/Reverse-geocoding services to translate between
coordinates and these names.

Gazetteers?

Games, and how they work.
Useful for self-reflection.
Are these gazetteers as well? In a way, they’re building up their own list of authoritative
named locations which is one of their main challenges and their main outputs, despite beinga game.

Geographic ontologies
What is an ontology?

I assume that most of us have an idea of what “ontology” means in the information
organization context, but just to re-cap (and from a philosophical bent): an ontology is a wayof dividing up the world (or a particular domain) into different types and describing therelationship between those types.
In geography, this is pretty clear, cities are parts of states are parts of countries. But also, I
can be within this zipcode which borders other zipcodes, but also within this county whichborders other counties.
Not all geographic ontologies are straightforward -- neighborhoods and the like have fuzzy
borders and different meanings to different people.

Where-on-Earth IDs (WOEIDs)
Hierarchy of official and informal places
Relationships to neighbors, parents, children
Freely available for download and web services

Useful for Geographic Information Retrieval: expanding queries

Personal ontologies
At home, at school, at work
On Bart, on the bus, on a planeWith my co-workers, my friends, my family
Where we first met, where I was at this time yesterdayUse cases
self-reflection
sharing and privacy
contextual triggers

Next steps

Matching up use cases to those different levels of meaning
What features does an ontology need to support these?
As a final project, build a version of this ontology, and services to contribute and consume

Questions?
npdoty@ischool.berkeley.edu
http://npdoty.name