Where2.0Now - Finding the heat in Thematic Maps

Where2.0Now - Finding the heat in Thematic Maps John Fagan Program Manager, Microsoft

1990’s – Sean Phelan’s vision

1996 - Multimap.com launched (no maps)

Desktop GIS - MapInfo Desktop for Power Mac v4

1997 - Multimap GeoStack MapInfo Desktop for power mac Hacked to make it serve maps over http Collins Bartholomew Raster maps Multimap.com gif.cgi Mapping API +Caching engine MySQL Bartholomew & OS Gazetteer places.cgi cache miss

MapInfo for Power Mac v4 Features
Local & Remote Data Access
Directly read dBase, Lotus 1-2-3, Microsoft Excel, delimited ASCII in native formats
Geocoding
Create points
Geocode to street address, ZIPcodes, census tract, user-definedmatch options
Map Creation and Editing
Raster map registration and display .GIF, .JPEG, .TIFF, .PCX, .BMP, .TGA, .BIL
Graphics Import
DXF
Digitizing to create vector images; supports digitizers
Autoscrolling to create or edit objects larger than the current window
Autotracing of existing object with mouse or digitizer
Clone Mapping to copy current map window
Customize map objects (fill patterns, line types, symbols, True Type fonts)
Map Editing Functions: Reshape objects, snap to editing, move objects, select multiple nodes for deletion, overlay nodes, copy objects, create polylines from regions, create regions from polylines, smooth / unsmooth, revert table, clear map objects only
Data Visualization
Create thematic maps using ranged shading, bar charts, pie charts, dot densities, graduated symbol and individual values
Range classification of maps based on equal count, equal ranges, inflection point, natural breaks, standard deviation, quantile, user defined
Combine thematic options to create maps that display multiple variables from many tables
Thematic joins based on: Count, sum, value, average, min/max, weighted average, proportional sum, proportional average, proportional weighted average
Attach data to any object
Multiple views Dynamically linked "hot" views of map, row & column, graph Page layout view District management browser/window display Legend window
Summary statistics window MapBasic command window Set layer display zoom
Zoom range 55 ft. to 100,000 miles Set layer display order View hundreds of layers Seamless map layers
Escape from map redraw
18 projections available On the fly transformation/display Overlay different projections Convert between projections
Analysis Capabilities
Get information about any object
Donut/island polygons supported
Polygon Overlay Operations Data aggregation / disaggregation, erase, erase outside, split, combine, overlay nodes
Buffers: Create buffers around any object or group of objects--points, lines, polylines, polygons
Geographic Selection
Find any object
Points within radius/polygon Lines/polylines within radius/polygon Polygons within radius/polygon
SQL/Advanced Querying Language Query based on expressions, perform aggregations, display derived fields, perform subqueries, do multi-table joins and perform geographic joins
Relational query operators
Standard and Geographic operators
Contain, contains entirely, within, entirely within, intersection/union

MapInfo for Power Mac v4 Features
Functions
Day, month, year, current date or weekday functions.
Change strings to upper, lower or proper case.
Find sin, cos, arcsin, arccos, sum, average, min, max, absolute value, exponential or rounded. · Find area, perimeter, length, and determine x/y centroid.
String functions
Conversion functions. Results can be treated as a separate table and saved as a separate database.
Aggregate functions from SQL queries
Group or sort data based on any field or expression. Sum, min, max, average, weighted average or count.
Statistics
Show count, total, mean, standard deviation, variance, range, min and max of a group of values.
Dynamically display sum and average of a selection.
Database Management
Create and change width or type of field, add/delete fields, index any field. Field types supported: character, floating point, integer, decimal, logical, date. Number of records limited only by hard disk storage; up to 250 fields per record.
Display and Presentation
Map Clipping to highlight region
Automatic or manual labeling
Label position by anchor point, offset distance, callouts
Text styles: bold, italic, underline, all caps, halo, boxed, shadow, double wide
True type fonts and text rotation
Hundreds of symbols and user created bitmaps
Unlimited number of colors
Scalable labels when zooming
Output
Print individual windows or layout
Printers/plotters: Supports any Windows compatible printer or plotter. Requires Windows-compatible driver included with Windows or from third-party vendor.
Output to Bitmap (.BMP) or Windows Metafile (.WMF)

Why should maps be for GIS Professionals only?

gif.cgi? pc=ec4a2dy

gif.cgi? pclist= ec4a2dy,ec1n2ns

gif.cgi?pclist= ec4a2dy,ec1n2ns& width=500&height=500

gif.cgi?pclist= ec4a2dy,ec1n2ns&width=500&height=500& ds=1

Multimap.com vs MapInfo
gif.cgi
simple, but scalable and accessible to all

Many customers still use gif.cgi today

>> Fast forward a few years

Visualisation – Heat Maps
Value interpolation
Frequency based
http://idvux.spaces.live.com/blog/cns!2EB6AAF6C3AC1EBE!1932.entry Heat is interpolated because it is a continuous data type. If it is 100 degrees at one station and 50 degrees at a neighboring station, it must be 75 degrees somewhere between the two. Heat brightness on the surface illustrates the frequency of crime reports

Choropleth map

Thematic Mapping API’s

Again, the web developers have come to the rescue and made GIS functionality accessible to all http://www.programmableweb.com/tag/thematic

Wait.... Do we want web developers to carry out spatial analysis?

....it could go wrong
Current API’s not fit for serious choropleth thematic analysis
Will result in committing wrong resources to the wrong problems in the wrong places
Need to understand underlying methods and limitations thereof
Need access to underlying data

Stan Openshaw and MAUP
The modifiable areal unit problem (MAUP) is a source of statistical bias that can radically affect the results of statistical hypothesis tests.
MAUP occurs when point-based measures of spatial phenomena (e.g., population density) are aggregated into districts , the resulting summary values (e.g., totals, rates, proportions) are influenced by the choice of district boundaries.
The issue was discovered in 1934. The term MAUP was first coined and described in detail by Openshaw (1984), who lamented that "the areal units (zonal objects) used in many geographical studies are arbitrary, modifiable, and subject to the whims and fancies of whoever is doing, or did, the aggregating. " (Openshaw, 1984, p.3).
The problem is especially crucial when the aggregate data are used for cluster analysis for spatial epidemiology, spatial statistics or choropleth mapping, in which misinterpretations can easily be made without realizing it.
http://en.wikipedia.org/wiki/Modifiable_areal_unit_problem

What if John Snow used todays API’s?

http://www.programmableweb.com/tag/thematic

One solution to Stan’s MAUP
Define your own areas by aggregating existing areas
Grab some admin areas that are small and uniform (with respect to attributes)
Enumeration Districts could work in UK
Haining (1990)

Aggregate areal units
Classify areal units based on cluster analysis using a large number of common variables related to the analysis you are carrying out
Deprivation indexes are often used for Epidemiology analysis
UK Deprivation indexes and associated variables

GIS could get this right in 1996

Bing Maps/SQL Server 2008

Aggregate areal units using STUnion ()
DECLARE @geom1 geometry
DECLARE @geom2 geometry
SELECT @geom1 = (SELECT GeomCol1 FROM FeatureTest WHERE blah)
SELECT @geom2 = (SELECT GeomCol1 FROM FeatureTest WHERE blah)
SELECT @geom1.STUnion(@geom2)
Union (here: Multipolygon)

View Choropleth overlays using Silverlight

Thematic Maps as Vector Data

Thanks john fagan ubergeo.com @johnbfagan

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Where2.0Now - Finding the heat in Thematic Maps

by John Fagan on Nov 11, 2009

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Where2.0Now - Finding the heat in Thematic Maps — Presentation Transcript