IntroductionDataMethodologySpatial AnalysisConclusion

Contact:

jchau@sfu.ca

Updated:

12.06.04

 

Data Acquisition

Greater Vancouver Regional District 2001 Census Data

  • Acquired from: Canadian Census Analyser @ CHASS (http://datacentre.chass.utoronto.ca/census/) Enumeration Area (old representation)/Dissemination Area (2001 representation)
  • Data fields extracted:
    • Income.dbf
    • Population.dbf

DMTI Datasets

  • Acquired From: DMTI Spatial
  • Data field extracted:
    • BCrds.shp from: DMTI CanMap Street files Version 7.2 2003/CanMap/BC/Streets/
    • BCmnwtr.shp and BCmjwtr.shp from: DMTI CanMap Water Version 1.2 2003/CanWater/BC/Water/

Greater Vancouver Regional District 2001 Census Shape File (Census2001_da.shp)

  • Acquired from: SFU GIS lab S-drive GEOG255 lab data

Downtown Eastside Map

Data Manipulation

Manipulations done in ArcMap

Census shape file (Census2001_da.shp)

  • Convert projection to NAD83 UTM 10N
  • Add new field to calculate area of each enumeration area within the shape file
  • Using MS Visual Basics code to calculate area of each polygon:

Dim dblArea as Double

Dim pArea as lArea

Set pArea = [shape]

dblArea = pArea.area

Census Base Raster Map (census_raster)

  • Convert feature (Census2001_da.shp) into raster format
  • Convert again into ASCII format for manipulation in IDRISI

Income (census2001_da_income.shp)

  • Attach income.dbf to census shapefile (Census2001_da.shp)
  • Export as shape file (income.shp)

Population Density (census2001_da_popdens.shp)

  • Attach population.dbf to census shapefile (Census2001_da.shp)
  • Create new field in attribute table
  • Use calculator to divide population by area
  • Export as shape file (popdens.shp)

Downtown Eastside Polygon (DowntownEastside.shp)

  • Create Personal Geodatabase with shape layer
  • Heads up digitized using editor toolbar

Major and Minor Waterbodies (BCmjwtr.shp & BCmnwtr.shp)

  • Convert projection to NAD83 UTM 10N
  • Manual selection and created new layer of significant waterbodies to the GVRD
  • Export as shape files (Van_mjwaterp.shp & Van_mnwaterp.shp)

DMTI Road Data (bcrds.shp)

  • Convert projection to NAD83 UTM 10N
  • Clipped with Census shape file
  • Merged within ArcMap Editor to decrease unique values
  • Export as shape file (van_roads.shp)

Manipulations done in IDRISI

Census Base Raster Map (census_base.rst)

  • Convert from ArcInfo raster ASCII format to IDRISI

Income (income.vct), Population Density (populationdensity.vct), DMTI Road Data (Van_roads.vct)

  • Convert from shape file to IDRISI
  • Open database file .MDB with MS Excel and delete all attributes except for unique ID and Average Family Income
  • Save as .CSV file and open in MS Word to replace all commas with spaces and save as .TXT file
  • Open .TXT file in IDRISI and save as .AVL file

Downtown Eastside Polygon (DowntownEastside.vct)

  • Convert from shape file to IDRISI

Major and Minor Waterbodies (mjwtr.vct & mnwtr.vct)

  • Convert from shape file to IDRISI

Further Manipulation by IDRISI Macro Modeler

Three main models were used to prepare the data for analyis

Batdata Model: Rasterization and preparation of data imported from ArcMap for spatial analyis:

  • Census Base Raster Map (census_base.rst) is used as the defining image.
  • Initial module is used to prepare blanks for each vector file
  • Lineras module was used to rasterize line data from the arc based road shape file van_roads.vct
  • Polyras module was used to rasterize polygon data from polygon shape income.vct, populationdensity.vct, DowntownEastside.vct, mjwtr.vct & mnwtr.vct
  • For data with attributes, the assign module was used to attach prepared corresponding .AVL files to the new raster files to produce Roads.rst, popdens.rst and income.rst.
  • The two water layers mjwtr.vct & mnwtr.vct were overlayed and combined to form one raster layer water.rst

MCE Model: Preperation of data for use in the MCE definition wizard

  • Census Base Raster Map (census_base.rst) was reclassed to a Boolean image (landcon.rst) to be used as a constraint in the MCE
  • The boolean raster image (waterways.rst) of the major waterways was produced using raster file of major waterbodies (raw_mjwater.rst)
  • A water cost distance raster image (water_costdist.rst) was made where land closer to the water were given higher values than land further away
  • Another cost distance raster image (dtes_costdist.rst) was made where the closer an area was to the Downtown Eastside were the larger the values it has

Least Cost Pathway Models: Used to determine the least cost pathways from the resulting optimal areas to Downtown Eastside. Several identical models were made for each area.

  • Data manipulation and anaylsis were done within this model please refer to Spatial Analysis page for analytical steps.

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