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Quality Assessment in grid statistics
Data quality and coverage
ESTP course on Geographic Information Systems (GIS): Use of GIS for making statistics in a production environmentStatistics Norway, Oslo, 26th to 30th of March 2012
Attribution (by) Licensees may copy, distribute, display and perform the work and make derivative works based on it only if they give the author or licensor the credits in the manner specified by these. http://creativecommons.org/licenses/by/3.0/
Mr Vilni Verner Holst BlochMSc Resourcs Geography and Landscape EcologyStatistics Norway460 Construction and service statisticsOterveien 23 N-2225 Kongsvinger [email protected]: +47 6288 5097Mob. +47 9482 2532
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Standard for Quality Reports
• To be interpreted into GIS terms- geographical accuracy- geographical coverage- georeferencing methods…
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Population and Housholds
unit
IT Archive unit
Housing andBuildings
unit
Population and housing example
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Statistics
• Dwelling statistics
• Housing census
• Constructions
• Builfing stock
• Levekårundersøkelser
Sources
• Properties register
• Population register
• Dwelling surveys
• Dwelling sales ingormation
• Ownership register
• Census 2001
• Actual addresses
• Elevator register
• Tax information
• Water supply maps
• Sewage maps
• …
Lot’s of variables, sources and statistics attached to dwellings
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Principles
• Use best sources :- use authorative sources first(e.g. …)
- use newest information(e.g. new dwelling sales before old…)
- imputation if enhancing statistics(coverage, detail level, bias etc…)
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Persons ”without dwelling
Inhabited dwellings
”vacant” dwellings
”new” dwellings
Micro file
ID
ID
N - 1 (often N – N, sometimes 1 - 0)
Published variables New variables
A B
C
persons
dwellings
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Percentage unknown
2006 2007 2008 2009 2010 2011
Urban/rural 1,06 0,13 0,08 0,04 0,05 0,11
Building year 9,12 9,46 9,21 9,02 8,42
Number of rooms 11,49 11,26 11,67 11,66 11,54
Utility floor space 7,67 7,10 6,59 5,84 5,33
Number of baths 11,06 10,85 11,19 11,05 10,88
Number of WC 10,98 10,78 11,12 10,95 10,79
Number of floors in building 0,50 0,08
Kitchen 0,88 0,93
Floor entrance 0,14 0,16
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08455: Dwellings, by number of floors in the building (M)
municipality unknown ↓
Kristiansand 4757
Oslo 656
Surnadal 446
Steinkjer 348
Drammen 193
Bardu 128
Tønsberg 124
Sandefjord 120
Sandnes 109
Halden 104
municipality Unknown ↓
Oslo 336
Åsnes 105
Volda 100
Grue 89
Flora 88
Frøya 69
Gaular 67
Øystre Slidre 56
Fauske 55
Hitra 53
08457: Dwellings, by position (floor) in the building (M)
Quality in dwelling statistics (municipalities)
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Water supply points from digital maps
Example water supply
Dwellings and distance to water supply
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Dwellings on gridsDwellings per 5x5 km grid cell
http://www.ssb.no/emner/01/01/20/tettstedkart/main.html
Oslofjord area Southern Norway mountains
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Dwellings on grids
http://www.ssb.no/emner/01/01/20/tettstedkart/main.html
Region Oslo Region Kongsvinger
Dwellings per 5x5 km grid cell
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Dwellings on gridsDwellings per 250x250m
http://www.ssb.no/emner/01/01/20/tettstedkart/main.html
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Quality in dwelling statistics on grid
2010
Missing On grid Statistics Difference %
Var Title (EN) 2010 2010 2010 2010
dwe_todw Dwellings in all 23 923 2 300 002 2 323 925 1,03
dwe_det Dwellings in detached houses 12 183 1 207 720 1 219 903 1,00
dwe_2dw Dwellings in tomannsboliger 2 911 208 685 211 596 1,38
dwe_row Dwellings in rekkehus, kjedehus og andre småhus 2 944 264 877 267 821 1,10
dwe_mult Dwellings in boligblokk 4 282 518 710 522 992 0,82
dwe_com Dwellings in bofellesskap 471 40 724 41 195 1,14
dwe_oth Dwellings in andre bygningstyper 1 132 59 286 60 418 1,87
dwe_avea Average utility floor space 109 123
Missing or incorrect coordinates. Norway.
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Dwellings with no information on utility floor space
Dwellings in all
Quality in dwelling statistics on gridCoverage for utility floor space. Whole country: 92,9 %
1x1 km grid cells in Trondheim area
60%
85%
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2008 - 2012
Change (N buildings) N (5x5 km)
+ 1 - 9 4 279 34,3
+ 10 - 99 2 496 20,0
+ 100 og mer 363 2,9
No change 3 638 29,1
Decrease 1 707 12 483 13,7
No buildings 8 264
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Buildings. Shares per 5x5 km2 and year. 2007-2012.
Inspection of changes. Changes in coordinates due to ”wash” of registers or real changes?
17Buildings. Change 2007 – 2012. 5x5 km2
Net more buildings
Net fewer buildings
Net more (red) and fewer (blue) buildings
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Buildings. Change 2007 – 2012. 5x5 km2
Real changes or due to different administrative routines?
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