The Spatial Web: Visions for a Geospatial World. Michael F. Goodchild Walton Fellow National Centre for Geocomputation

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1 The Spatial Web: Visions for a Geospatial World Michael F. Goodchild Walton Fellow National Centre for Geocomputation

2 Outline Context Current technology My own research Technological vision Social issues

3 How do we know where we are? The senses position relative to other objects distance direction Being lost no other objects in sensory range the objects in range are not identifiable

4 Wayfinding skills Landmark knowledge a list of places no spatial relationships no adjacency "if this is Tuesday it must be Belgium" no spatial context "how long is this flight?" no intervening places no wayfinding ability

5 Tract Pop Location Shape x,y x,y x,y x,y x,y x,y x,y x,y

6 Route knowledge Sequences of intervening places no ability to short-cut no directions, distances context along the route but not off Chatwin s songlines

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12 Survey knowledge Full two-dimensional representation distances orientations shortcuts context vertical and horizontal Registered to an absolute Earth frame latitude and longitude

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21 GOS coverage, 1/06

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25 Interoperability The ability to use data from any system in any system several hundred recognized formats for geospatial data Standard protocols Open Geospatial Consortium CEN, ISO GML, WCS, WFS, WMS

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27 The problem of semantic interoperability

28 Soils Classification Schemes Petén Simmons (1959). USDA. Only data set with soil attributes for Drainage and Fertility Mexico Modified FAO/UNESCO (1969) Belize Wright (1959). British Honduras Land Use Survey Team.

29 x 10 6 Population for counties x 10 6 Population for watersheds=? x x 10 5

30 Areal interpolation Given a set of non-overlapping, spaceexhausting source zones counties with attributes Estimate attribute values for a second set of non-overlapping, spaceexhausting target zones that cut the source zones

31 4 source zones A 1 target zone B 15% of B C 10% of A D 5% of C 50% of D Pop TARGET = 0.10 Pop A Pop B Pop C Pop D

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33 The general idea Areal values are treated as averages or integrals of an underlying, but unknown point-support field A covariance model of the point-support field is known or can be estimated The shape of that covariance model influences the smoothness of the areal values σ Z Z ( ) σ 0 ( u u' ) σ Z ( ) σ 0 Z ( u u' ) u u' u u'

34 Synthetic data example (1) Realization of Gaussian random field on a 300x300, unit cell, regular grid mean = 100 spherical semivariogram model range = 50 (isotropic) sill = 300 Simulated latent point field Source data Target values Source and target supports = random Voronoi polygons Intensive variables (averages)

35 Synthetic data example (2) Kriging predictions Kriging std errors Execution times* (for a 360x360 embedding domain) Traditional method: ~4,000 sec Spectral method: ~50 sec *Matlab 7 running on a Pentium 4 Dell Dimension 8300 PC at 3.2GHz with 2GB RAM

36 Geo-browsers Easy access to the spatial data infrastructure Google Earth Google Maps, Google Local Microsoft Virtual Earth ESRI GIS Explorer

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38 Major features Internal data structure hierarchical tesselation Web transactions the numbers level-of-detail management thick client 32MB graphics card Layered Oblique perspective, flyby KML programming interface integrating other data distributed interoperable sources Child of ten can do it

39 Positioning technologies Navigation sextant chronometer

40 Positioning technologies Surveying measurement with respect to a known point tape, compass, clinometer GPS, Galileo accurate timing of signals from satellites easily incorporated into mobile devices

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42 Dynamic geographic information Live feed to desktop, laptop, mobile phone integrated with other map data

43 RFID Radio frequency identification scanning without the laser active or passive Tracking of objects goods from production to retail display to sale

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45 Sensor networks Small, cheap devices smart dust digital dust Sensing ambient properties uploading to central site

46 Firebugs (UC Berkeley) Motes distributed in advance of a fire compare to problems of overflight GPS or RFID positioning

47 The spatial web Objects that know and report where they are together with other information Servers that compile and distribute information Users who can combine data from various sources NPR audio clip

48 Augmenting the senses Providing direct sensory connection to objects that are beyond sensory range beyond physical range information is beyond sensing compensating for lost or diminished senses an augmented sensory reality

49 Social issues Locational privacy public persona traded for convenience, security travel patterns can often distinguish between genuine use and criminal use calling emergency services private persona never shared

50 They are always watching you. Use cash. Do not give your phone number, social security number or address. Do not fill in questionnaires. Demand that credit firms remove you from marketing lists. Check your medical records often. Keep your telephone number unlisted. Never leave your mobile phone on. Do not use credit or discount cards. If you must use the Internet, use someone else's computer. Assume that all calls, voice mail, and computer use are monitored. The Economist, 1 May 1999

51 The mirror world The spatial web is selective whose agenda does it serve? Spatial data cannot be perfectly accurate what are the consequences of error and vagueness?

52 Military and intelligence uses Often the original motivation for development Google Earth GPS remote sensing

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55 An active partnership The academic world training and educating the next generation basic and applied research reflection and commentary Industry basic and applied research bringing ideas to market Government a major source of geographic data basic and applied research policies, standards, regulation

56 Concluding points Our ability to acquire, distribute, and use geographic information is growing rapidly no longer confined to the content of maps The Internet and Web provide the means to assemble and disseminate geographic information at electronic speed, in real time cheaply and accurately

57 Concluding points (2) The broader implications of these trends demand the attention of the academic sector It was premature to announce the Death of Distance (Cairncross, 1997) There is no more there, everywhere is here (MCI ad, circa 1998) the world of the Internet is very much a spatial world