Calculation of commutingdistances in ArcView 3'x

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Calculation of commuting-distances in ArcView
3.x

• Michael Berg Rasmussen
• Statistics Denmark

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Register-based labour force statistics (RAS
statistics)

• RAS contains
• Adress of residence
• Adress of workplace

• Commuting-statistics today
• how many people working in a municipality are
  coming from another municipality
• how many people living in a municipality are
  working in another municipality

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Register-based labour force statistics (RAS
statistics)

• but if we could get to know the distance people
  actually have to travel from their residence to
  their workplace, it would be much better

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Materials for making commuting-calcultions

• RAS (Adresses of residence and workplace)
• KDV (Digital network of roads)
• Network Analyst for ArcView 3.x

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Possibilities with Network Analyst

• Network Analyst measures out the shortest route
  by car between two adresses through a network of
  roads
• The routes are measures one at a time

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Many at a time

• Two AvenueScripts
• Script1 Geocodes all the addresses by the postal
  address and returns the x,y-coordinates
• Script2 Geocodes the adresses of residence and
  workplace by the x,y-coordinates and returns the
  roaddistance between them

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No solution without irregularities!
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Problems with the workplaces in RAS

• But sometimes they look like
• 950 0000 000 (people working in another country)
• 101 0000 000

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Problems in KDV - The attributes

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Problems in KDV - Technical mistakes (1)
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Problems in KDV - Technical mistakes (2)
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Problems in KDV - Technical mistakes (3)
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The calculations can begin!
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Step 1

• All adresses of residence and workplace are
  geocoded by their postal adress and their
  x,y-coordinates are returned

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Step 2

• All residence-/workplace-relations with
  coordinates have their mutaul road-distance
  calculated
• 90.4 of all residence-/workplace-relations are
  now calculated

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Step 3

• BAK-coordinates (free download from the homepage
  of KMS) are joined with the adresses which did
  not get a coordinate-value in step 1
• BAK-coordinates must be transferred to a point
  (RoadCenterPoint) on a road

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Step 4

• Residence-/workplace-relations involving
  BAK-coordinates are calculated
• 91.5 of all residence-/workplace-relations are
  now calculated

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Step 5

• Bigger workplace gt 100 employed are manual found
  by searching in KDV
• 91.8 of all residence-/workplace-relations are
  now calculated

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Step 6

• Municipality-center of gravity for residence and
  workplace are calculated

Municipality-center of gravity
Average(X),Average(Y)
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Municipality-center of gravity for residence and
workplace

• The coordinates for the centers of gravity are
  used where an adress for some reason are without
  coordinates or are situated inaccessible for
  distance-calculations
• F.ex. 0000-workplace-adresses

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Step 7

• The remaining residence-/workplace-relations are
  calculated in this way
• 99.7 of all residence-/workplace-relations are
  now calculated
• The remaining relations are people working in a
  foreign country

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Main result

• People in Denmark travels on an average 15½ km in
  order to go to work from their residence