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Distance from home

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|+ '''Casualty average distances from home in kilometres - Britain 2004 to 2008'''
|+ '''Casualty average distances from home in kilometres - Britain 2004 to 2008'''
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!Road Class!! !! !!M!! !! !!A and B!! !! !!Other!! !!All
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!Road Class!! !!M!! !! !!A and B!! !! !!Other!! !!All
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!Casualties!!Urban!!Rural!!Overall!!Urban!!Rural!!Overall!!Urban!!Rural!!Overall!!Overall
!Casualties!!Urban!!Rural!!Overall!!Urban!!Rural!!Overall!!Urban!!Rural!!Overall!!Overall

Revision as of 13:32, 11 February 2010

Distance from home is a measure built into MAST which is based on a calculation of the distance in kilometres between a crash location and the home address of each person involved. MAST aggregates all the results of this calculation, and expresses them as averages for all individuals included, summarised by dimensions as required.

MAST has calculated distance from home for both drivers and casualties.

Interpreting Distance From Home

The absolute average distance from home numbers are often not very meaningful in themselves, especially over large sample sizes. The value of this measure lies principally in identifying and examining cases which are significantly different from the norm.

It is also important to understand that distance from home is likely to vary considerably between crashes on different Road Class. It will also differ between modes of transport, taking into consideration vehicle types and casualty class.

Casualty average distances from home in kilometres - Britain 2004 to 2008
Road Class M A and B Other All
CasualtiesUrbanRuralOverallUrbanRuralOverallUrbanRuralOverallOverall
Motorcycle User 32.6 49.9 46.8 9.7 26.1 16 5.4 11.2 6.9 13.4
Car User 37.2 61.3 58.1 11.1 25.9 18.6 7.3 12.9 9.2 18.3
Bus User 67.7 139.1 133.8 7.6 25.2 10.3 5.7 13.2 6.6 10.9
Goods Vehicle User 53.9 76.6 74.4 22.1 44.2 36.5 13.8 23.4 18.1 37.8
Pedal Cyclist 4 7.2 5.6 5.2 11.7 6.4 2.9 8.7 3.8 5.1
Pedestrian 16.6 48 39.2 7.4 16.2 8.7 6 11.6 6.7 7.6
Overall 38 63.1 59.8 10.1 26.3 17.3 6.5 12.8 8.2 16.3

Calculation algorithm

The method of calculation for each individual is as follows:

  1. MAST checks if a valid postcode was recorded for the individual in STATS19, and if so looks up the NSGR of the centre point of that postcode
  2. MAST checks if the NSGR supplied for the crash location in STATS19 falls within the National Grid
  3. If both these NSGR references are valid, the distance between these two points is calculated using Pythagoras' theorem; these results are then aggregated in the measure to calculate an average
  4. If either or both NSGR references are suspect or missing, then that individual is entirely excluded from calculation of the average
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