Greek Cadastre
Quality Model and Quality Checking
of spatial cadastral data
Ioannis Kavadas
Rural & Surveying Engineer, MSc, Ph.D. Candidate
Ktimatologio S.A.
Head of Project Quality Management & Control Department
1
Reykjavik, 31/05/2012
QKEN – Plenary meeting
2
Greek Cadastre – background & key goals
 The Greek cadastre is being created
 Expected - planned completion in 2020
Rights-based, is:
a. 18% complete
•
Municipalities: 336 (of a total of 5775)
•
Area: 8.738 km2
•
Cadastral parcels: 1.748.795
•
Properties: 3.500.824
•
Rights: 6.728.839
•
Spatial corrections in the 8-year operation
of cadastral offices: 13.500 (0,8%)
b. 22% in implementation (major cities)
c.
19% has been launched
d. 41% will be launched in 2012
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – cadastral data acquisition
(1)
The spatial cadastral data derived
from:
 the cadastral survey process
 digitizing the obvious materialized
parcel boundaries on orthophotos
 spatial cadastral data are included in
administrative acts after joining the
geodetic reference system of
National Cadastre
 boundaries of coastal areas and
forest areas
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – cadastral data acquisition
The spatial cadastral data derived
from:
 verification of spatial data using the
data collected in the collection of
owners statements – topographical
diagrams
 spatial data from property titles
(area, length of parcel sides e.t.c.)
 participation of the owners (indicate
cp boundaries)
Reykjavik, 31/05/2012
QKEN – Plenary meeting
(2)
… location “Katsouli” of the
territory of the Municipality
of Salamis, not included in the
urban development zones, shown
with the upper case letters AB-C-D-A
on
the
topographic
diagram that was drawn by the
architect engineer E… M… and is
attached to my November 19,
1993, contract, has an area of
one hundred and eighty five and
90/100 (185.90) sq. meters and
borders,
according
to
the
diagram, on the North and along
the face C-D that has a length
of fifteen and 60/100 (15.60)
meters with the property of E…
Ps…, on the South, along the
face A-B that has a length of
fifteen (15) meters with a four
(4) meter wide road, on the
East and along the face B-C
that has a length of eleven and
80/100 (11.80) meters with a
property of unknown owner, and
on the West, along the face A-D
that has a length of twelve and
50/100 (12.50) meters, with a
four (4) meter wide road.
The
same land parcel is also shown…
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Greek Cadastre – basic notions and key requirements
 The Greek cadastre is being created
 Every part of land at the municipal
level (including roads, streams, special
areas etc.) are cadastral parcel
 The spatial information is fully
connected with legal and property
information
 For the creation of spatial data, we
have recent (2009) and complete
(full coverage) reference data
 Use of Hellenic Positioning System
(HEPOS) in field measurements
 Involving property owners in the
process (statements / objections)
 Partially created using External
Contractors
 If detected errors or non conformities
in the data are corrected by the
contractor
HEllenic
POsitioning System is a system that provides
high-accuracy satelite-based real-time positioning
services
The using
management
of spatialSystem
data (GPS).
is
the Global Positioning
HEPOS
consists
of 98 permanent GPS reference stations
fully
digital
and has been designed and developed by KTIMATOLOGIO
S.A., witch also operates the system. www.hepos.gr
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – General Conceptual Model
(1)
Feature types
Topological relationships
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – General Conceptual Model
(2)
Cadastral zoning
Administrative unit
Cadastral parcels
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – Spatial feature catalog
Layer
Description
Feature type
INSPIRE object
PST
Cadastral parcels
Polygon
Cadastral parcels
ASTOTA
Municipality boundaries
Polygon
Administrative Unit (cz)
ASTTOM
Cadastral sectors
Polygon
Cadastral zoning
ASTENOT
Cadastral sections
Polygon
Cadastral zoning
MRT
Mining areas
Polygon
Cadastral zoning
BLOCK_PNT
XYZ Control points
point
Other
VST
Independent buildings (Vertical ownerships) Polygon
Other
EAS
Ways of passage (Servitude)
Polygon
Other
BLD
Buildings
point
Other
ASTIK
Urban areas
Polygon
Cadastral zoning
EIA
Special property objects
Polygon
Cadastral parcels
EIA_PNT
Special property objects
point
Cadastral parcels
Roads
Road network
Line
Other
OIK
Settlement boundaries
Polygon
Administrative Unit (cz)
CBOUND
Boundaries of urban zone areas
Polygon
Cadastral zoning
Polygon
Cadastral zoning
DBOUND
Administrative acts (consolidations, land
distributions, urban consolidation plans)
FBOUND
areas
Polygon
Cadastral zoning
NOMI
Land tenure (property possession)
Polygon
Cadastral zoning
POI
Points of interest
Point
Geographical names
POL
Parcel identification marks
Point
Other
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre – Data model basic
requirements and constraints
For all cadastral data are not overlapping
entities within the same layer
The ASTOTA polygon must be composed
entirely of ASTTOM polygons
The ASTOTA polygon must be composed
entirely of PST polygons
The ASTOTA polygon should include entirely
ASTIK polygons
The ASTENOT polygons should be included
in the ASTTOM polygons
The ASTIK boundaries should not intersect
with the boundaries of the PST polygons
The VST polygons should be included in the
PST polygons
The EAS polygons should be included in the
PST polygons
The BLD points should be included in the
ASTOTA polygon
The MNT polygons should be included in the
ASTOTA polygon
The EIA polygons should be included in the
ASTOTA polygon
The EIA_PNT points should be included in
the ASTOTA polygon
The CBOUND polygons should be included
in the ASTOTA polygon
The DBOUND polygons should be included
in the ASTOTA polygon
The FBOUND polygons should be included
in the ASTOTA polygon
The NOMI polygons should be included in
the ASTOTA polygon
The BLOCK_PNT, POI and POL points
should be included in the ASTOTA polygon
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Reykjavik, 31/05/2012
QKEN – Plenary meeting
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INSPIRE Cadastral parcels – General Conceptual Model
Basic property unit
+ INSPIRE identifier
+ temporal information
+ national cadastral reference
+ area value
Cadastral
Zoning
Cadastral
Parcel
Cadastral
Parcel
Temporal Information
+ begin lifespan
+ end lifespan
+ valid from
+ valid to
Cadastral
Boundary
0…n
Cadastral boundary
+ INSPIRE identifier
+ temporal information
+ geometry
+ estimated accuracy
Reykjavik, 31/05/2012
1..2
Cadastral parcel
+ INSPIRE identifier
+ temporal information
+ geometry
+ national cadastral reference
+ area value
+ reference point (portrayal)
+ label (portrayal)
0..1
QKEN – Plenary meeting
0..1
Cadastral zoning
+ INSPIRE identifier
+ temporal information
+ geometry
+ national cadastral zoning reference
+ name
+ level (hierarchy)
+ level name (hierarchy)
+ original scale denominator
+ Estimated accuracy
+ reference point (portrayal)
+ label (portrayal)
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Greek Cadastre GCM vs INSPIRE GCM
(1)
140210914003
dataset
Temporal
information
is also
available
003
Cadastral diagram
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek Cadastre GCM vs INSPIRE GCM (2)
140210914
identified in data
model for every Cz
dataset
09
Temporal
information
is also
available
14
Cadastral diagram
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(1)
Full Inspection
Sampling
Sampling
If there are errors (error number> 0) the subset
should be rejected, and a report with corrective
actions prepared and sent to the contractor
FGDC : Geospatial Positioning
Accuracy Standards - Part 3: National
Standard for Spatial Data Accuracy
ISO 2859
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(2)
DQ basic measure / error count: id 2 (ISO 19138)
Quality element Completeness
Quality sub element Commission
Quality measure Number of excess items
Scope All items classified as “cadastral parcel” in the dataset.
Measure Error count
Measure definition Number of items within the dataset that should not have been
in the dataset.
Result value type Number (integer)
Result unit count
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(3)
Requirement: Every part of land at the
municipal level are cadastral parcel
DQ basic measure / error count: id 2
Evaluation Number of cadastral parcels,
method which are not presented in the
description dataset (in relation to cadastral
parcels in the universe of
discourse)
QC Range Full inspection
QC procedure Automatic
Reference data Municipality boundaries
Software
QCR type /
format
Conformance
level
Sample:
Custom application, ArcGIS
List / KAEK in MSExcel
Zero violations in dataset
33 municipalities
280.781 parcels
Part of qcr checklist
Quality requirement: Completeness
Conformance level: Absence of area gaps within
the municipality boundaries
Result: Accepted
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(4)
Key note: The spatial information is fully
connected with legal and property information
DQ basic measure / error count: id 2
Evaluation Number of cadastral parcels,
method which are not presented in the
description dataset.
Every cadastral parcel included in
the database of property
information is also included in the
spatial data and vice versa (1:1)
QC Range Full inspection
QC procedure Automatic
Reference data Database with ownership and
property data
Software
QCR type / List - KAEK in MSExcel
format
Conformance Zero violations in dataset
level
Sample: 33 municipalities
280.781 parcels
Reykjavik, 31/05/2012
Part of qcr checklist
Quality requirement: Completeness (spatial vs
property data 1:1 identification)
Conformance level: For each property record
there is a corresponding cadastral parcel and vise
versa
Result: Not accepted
Report: KAEK of non-compliant cadastral parcel
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(5)
DQ basic measure / error count: id 19 (ISO 19138)
Quality element Logical consistency
Quality sub Format consistency
element
QC procedure Automatic full inspection
Conformance Zero violations in dataset
level
Part of quality report
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(6)
DQ basic measure / error count: id 25 (ISO 19138)
Quality element Logical consistency
Quality sub Topological
element consistency
QC procedure Automatic full inspection
Conformance Zero violations in dataset
level
Part of quality report
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(7)
DQ basic measure / Mean value of positional uncertainties: id 28 (ISO 19138)
Quality element Positional accuracy
Quality sub element Absolute accuracy
Quality measure Mean value of positional uncertainties / id 28
Scope All items classified as “cadastral parcels” set in the dataset.
Measure Root Mean Square Error (RMSExy)
Measure definition Geometric accuracy of cadastral parcels with regard to the
adopted geodetic reference system (EGSA’87).
Result value type measure
Result unit -
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(8)
DQ basic measure / Mean value of positional
uncertainties: id 28
Evaluation Mean value of the positional uncertainties for
method a set of positions where the positional
description uncertainties are defined as the distance
between a measured position and what is
considered as the corresponding true
position.
QC Range Sampling using FGDC standards
Based on “Geospatial Positioning Accuracy
Standards - Part 3: National Standard for
Spatial Data Accuracy”, Subcommittee for
Base Cartographic Data / Federal
Geographic Data Committee
QC procedure Field measurements
Reference data -
Software GPS receiver and Total Station / ArcGIS and
Autocad
QCR type / format MSExcel file & Shapefile
Conformance Urban areas: RMSExy ≤ 0,56m
level Agricultural & other areas: RMSExy ≤ 1,41m
Sample: 33 municipalities
2.556 control points
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(9)
DQ basic measure / Relative horizontal error
Quality element Positional accuracy
Quality sub element Relative accuracy
Quality measure Relative horizontal error
Scope All items classified as “cadastral parcels” set in the dataset.
Measure Parcel’s shape compatibility (1st )
Parcel’s boundary’s length compatibility (2nd and 3rd)
Measure definition Evaluation of the random errors in the horizontal position of
one feature to another in the same dataset
Result value type measure
Result unit -
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(10)
DQ basic measure / Relative horizontal error
Evaluation Check the compatibility of the parcel shape
method compared to the "Compatibility Zone" of the
description cadastre parcel.
Parcel’s shape compatibility, is true when all
points of the outline of parcel on the
topographic diagram can be placed in the
"Compatibility Zone" of the cadastre parcel.
QC Range Sampling inspection using Procedure A of
ISO 2859-2 standard
QC procedure Manual
Reference data Topographical diagrams (collected with
owners statements) and diagrams from
administrative acts
Software ArcGIS
QCR type / format MSExcel file & Shapefile
Conformance LQ=8,0
level
Sample: 33 municipalities
2400 parcels
Reykjavik, 31/05/2012
Compatibility Zone defined as the zone which
lies between border of an inner and an outer
polygon with sides parallel to the sides of the
cadastral parcel, located on either side as follows:
• Uo = 0,50m for urban areas
• Uo = 2,00m for non urban areas
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(11)
DQ basic measure / Relative horizontal error
Evaluation Compare the length of the boundary of the
method parcel as measured in the field with the
description same length in the spatial database
QC Range Sampling inspection
2~3 cadastral sections (blocks) per
municipality.
With the new technical specifications, we
increased (three times) the number of the
inspected parcels
QC procedure Field measurements
Reference data Software GPS receiver and Total Station / ArcGIS and
Autocad
QCR type / format MSExcel file & Shapefile
Conformance Urban areas: Es ≤ 0,79m
level Agricultural & other areas: Es ≤ 1,99m
Sample: 33 municipalities
1350 parcels
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(12)
DQ basic measure / Relative horizontal error
Evaluation Compare the length of the boundary of the
method parcel as measured or shown in
description topographical diagram with the same length
in the spatial database
QC Range Sampling inspection
5~7 parcels per municipality.
With the new technical specifications, we
increased (three times) the number of the
inspected parcels.
QC procedure Manual
Reference data Topographical diagrams (collected with
owners statements)
Software ArcGIS
QCR type / format MSExcel file & Shapefile
Conformance Urban areas: Es ≤ 0,79m
level Agricultural & other areas: Es ≤ 1,99m
Sample: 33 municipalities
224 parcels
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QKEN – Plenary meeting
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Greek QM for cadastral parcels
(13)
DQ basic measure / error count: id 62 (ISO 19138)
Quality element Thematic accuracy
Quality sub element Classification correctness
Quality measure Number of incorrectly classified features
Scope All items classified as “cadastral parcel” in the dataset.
Measure Error count
Measure definition Number of incorrectly classified features
Result value type Number (integer)
Result unit count
Reykjavik, 31/05/2012
QKEN – Plenary meeting
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Greek QM for cadastral parcels
(14)
Requirement: Every part of land at the
municipal level are cadastral parcel
DQ basic measure / error count: id 62
Evaluation Visual inspection based on the
method delineated boundaries of the
description properties as shown on
orthophotos.
QC Range Full inspection
QC procedure Manual
Reference data Orthophotos
Software
QCR type /
format
Conformance
level
Sample:
ArcGIS
Shapefile
Zero violations in dataset
33 municipalities
280.781 parcels
Reykjavik, 31/05/2012
data inspection also for:
 Presence of blunder errors mainly in the
shape of parcels
 Existence of drawing faults
 Systemic movement of parcel boundaries
 Existence of discontinuities in the entities
QKEN – Plenary meeting
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Conclusions
The results of quality control performed in 6 resent contracts (33 municipalities / with
new specifications) meet compliance criteria set in the specifications.
To accept the data needed 1 to 3 (max 5) re-submissions by the data producer with
corrections or clarifications resulting from our quality checking.
The project's success is mainly based on following factors:
Using both the data producers and Ktimatologio S.A. detailed quality plan based
on ISO 10005,
Mandatory implementation of internal quality checking by the data producer
(similar with quality controls of Ktimatologio S.A.) and submit their results to us
for checking and validation,
Implementation of quality checking from the Ktimatologio S.A using quality plan
and detailed quality manual, trained staff and specialized software applications,
The effectiveness of quality checing that adopted by Ktimatologio S.A., which
resulted very small percentages of appeals and requests for correction by owners avg 1% (in total of 280.781 parcels) for spatial data during the suspension of data
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Thank you for your attention
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