Geospatial Data Quality Control in IBGE

International Workshop on Geospatial Data Management and Quality Control

Tianjin, China, 12-16 December 2016

Country Report of Brazil

Alex da Silva Santos (Mr)

SUMMARYØ Introduction

Ø Objectives

Ø The National Spatial Data Infrastructure of Brazil (INDE)

Ø Norms, standards and documents of INDE

Ø Evaluation of the quality of geospatial data in IBGE

Ø Methodology of evaluation of the quality geospatial dataset

Ø Construction of data quality measures

Ø Data quality control management

Ø Visualizations of uncertainties

Ø Capacity in geospatial data quality

Ø Participation and dissemination in events

Ø Future expectations

Ø Final considerations

Ø References

OBJECTIVES

The main objectives of this presentation are:

Ø To show the adoption of standards in Spatial Data

Infrastructure (SDI) of Brazil.

Ø To emphasize the importance of standardizing the data

quality control of geospatial data in SDI.

INTRODUCTION

The Brazilian Institute of Geography and Statistics (IBGE) portrays the

Country and society using geographic and statistical information.

According to constitutional norms of Brazil, IBGE is responsible for the

National Statistical System and the Brazilian Geodetic System (SGB).

The IBGE is disseminator and producer together with the Geographic Service

Directorate of the Army and other institutions belonging to the National

Cartographic System,

National Cartography Commission (CONCAR)The National Cartography Commission (CONCAR) is responsible for the

management of the National Cartographic System.

The CONCAR is formed by technical’s committees and coordinated by the

Ministry of Planning.

Figure – Some institutes, agencies, states and counties in CONCAR's technical committees

IBGE is present throughout the national territoryBrazil is a country with the dimensions of a continent, with a diversity of

environmental, social and cultural information.

To carry out its activities, IBGE is

present throughout the national

territory, with units in its twenty-

seven states, one in the Federal

District and agencies in more than

five hundred Brazilian counties.

Figure - IBGE is present throughout the national territory

Population: more than 200 millions inhabitants

Official territorial area8.515.767,049 km2

Territorial division27 states1 (one) Federal District5570 counties

IBGE regional geosciences managementTo assist the mapping activities, in seven states there are also units of

Management of Geodesy, Cartography (GGC) and Natural Resources

(GRN).

Figure - Coverage area of IBGE regional geosciences management

THE NATIONAL SPATIAL DATA INFRASTRUCTURE OF BRAZIL (INDE)The Legal Framework Brazil's Spatial Data Infrastructure (SDI), took place

on November 27, 2008, with Presidential Decree No. 6,666, establishing the

National Spatial Data Infrastructure - INDE.

Figure - National Spatial Data Infrastructure of Brazil (INDE) Geoportal www.inde.gov.br

Action Plan for the Implementation of the INDE

The document called "Action Plan for the Implementation of the

National Spatial Data Infrastructure” guides the implementation of

Brazil's spatial data infrastructure.

Figure - Action Plan for the Implementation of INDE

This document elaborates the

development of a series of norms,

standards and technical

specifications for geospatial data.

NORMS, STANDARDS AND DOCUMENTS OF INDE

The INDE Decree Law regulates public

mapping institutions in Brazil to follow

the norms, standards and technical

specifications approved by the

National Cartography Commission

(CONCAR) and to publish their

geospatial data with their metadata,

according to Brazil’s Geospatial

Metadata Profile.

Figure – Brazil’s Geospatial Metadata Profile(based on ISO 19113:2003)

NORMS, STANDARDS AND DOCUMENTS OF INDE

The norms, standards and technical specifications

developed by CONCAR's technical committees are based

mainly on the ISO 19100 series of standards, which refer

to geospatial data.

In addition, the Geocentric Reference

System of the Americas (SIRGAS

2000) has been definitely adopted as

geodetic reference in Brazil.

Figure – SIRGAS 2000

EVALUATION OF THE QUALITY OF GEOSPATIAL DATA IN IBGE

The Coordination of Cartography

(CCAR) of the IBGE Directorate

of Geosciences (DGC) has been

adopted ISO 19157: 2013 for the

quality control activities of its

cartographic bases and other

cartographic products.

Figure – ISO 19157:2013

Quality elements of quality

The quality assessment is based on the quality elements and guidelines of

ISO 19157: 2013Table – Elements and sub-elements of quality

Element Sub-element

CompletenessCommission

Omission

Logical consistency

Conceptual consistency

Domain consistency

Format consistency

Topological consistency

Positional accuracy Absolute accuracy

Relative accuracy

Positional accuracy of the data in the grid

Thematic accuracy Correction of classification

Degree of correction of quantitative attributes

Accuracy of quantitative attributes

Temporal accuracy Accuracy of a temporal measure

Temporal consistency

Temporal validity

Usability

METHODOLOGY OF EVALUATION OF THE QUALITY OF GEOSPATIALDATASET

The flowchart presents the overview of the methodology of evaluation of the

quality of cartographic products.

Figure- Flowchart for geospatial data quality assessment (based on ISO 19157:2013)

Quality Evaluation Inspection method

Sampling inspection

Thorough inspection

Metadata Inspection results

Specification of product or user requirements

Spatial dataset

Data Quality Measures Catalog

Class of occurrence of quality measure (vector format)

CONSTRUCTION OF CATALOGS OF DATA QUALITY MEASURES

The importance of the construction of catalogs of data quality measures to

standardize the quality measurement, to facilitate the fitness for use and to

allow the comparison of quality between different cartographic products.

Figure- Construction of catalogs of data quality measures

Excess items

Positional accuracy

Missing items

DATA QUALITY CONTROL MANAGEMENT

The classes of occurrences shown in Figure are stored in geographic databases.

However, CCAR's geographic database structure needs to be adequate for ISO 19157:

2013 guidelines for quality control management.

Figure- Class of occurrences to assist the management and quality control of cartographic products

VISUALIZATIONS OF UNCERTAINTIES

The Coordination of Cartography (CCAR) intends to incorporate in the

quality reports, provided for in ISO 19157: 2013, when possible, the

visualization of uncertainties of the geospatial data set.

Figure - Visualizations of uncertainties (Quality Maps)

Missing items of hidrography

Excess items of hidrography

Positional accuracy in 1:250.000 scale

CAPACITY IN GEOSPATIAL DATA QUALITY

In the year 2016, internal and external courses of “Introduction to

assessment quality of geospatial data" were carried out for IBGE

employees. The objective was to enable them to use the methodology of

geospatial data quality assessment. Some of these courses were:

• Internal training at the headquarters and in the Management of Geodesy and

Cartography of the Federal District and Goiás (GGC-DF and GGC-GO).

• External training to assist partner institutions in assessing the quality of their

geospatial data. The objective is to facilitate the adaptation to the use of these

cartographic bases in the mapping of Brazil, avoiding the duplication of efforts and

guaranteeing the quality of the information.

PARTICIPATION AND DISSEMINATION IN EVENTSThe IBGE, through participation in events at national level, encourages the use of

international standards for the measurement of cartographic products.

During the week of December 5 to 9 there was a session in the 3rd National

Conference of Producers and Users and Statistical, Geographical and

Environmental Information of IBGE to propose minimum parameters and data

quality measures for the measurement of cartographic products.

Figure- 3rd National Conference of Producers and Users of Statistical, Geographical and Environmental Information (INFOPLAN)

FUTURE EXPECTATIONSThe expectations of IBGE are:

• To qualify the other units of the Directorate of Geosciences to evaluate the quality of

geospatial data.

• To structure the geographic database for data quality control management.

• To publish technical manuals for geospatial data quality evaluation.

• To prepare and propose, together with other institutions of CONCAR, the

standardization of a set of minimum quality measures to be used by INDE institutions.

• To incorporate the quantitative quality measurements according to ISO 19115: 2003

into the geospatial metadata.

• To standardize the quality measurement, during the production and delivery stages

of the cartographic product, in the areas of the institution.

FINAL CONSIDERATIONS

The participation of different mapping institutions, academic or production, in

events at a global level, is essential for the sharing of knowledge and

experiences that guide visions and expectations.

The standardize of mapping standards, assessing the quality and availability of

geospatial information are essentials for implementation of the Sustainable

Development Goals.

The IBGE represents the country and is always active in local, national,

regional and global issues.

REFERENCESCONCAR, National Commission of Cartography. Action Plan for the Implementation

of the National Spatial Data Infrastructure. CONCAR, 2010.

CONCAR, Comissão Nacional de Cartografia. Perfil de Metadados Geoespaciais do

Brasil – Perfil MGB. CONCAR, 2009.

ISO 19115. Geographic Information – Metadata. International Standardization for

Organization, Genebra, Suíça. 2003.

ISO 19157. Geographic Information – Data quality. International Standardization for

Organization. ISO TC/211 Secretariat, Genebra, Suíça. 2013.

SANTOS, A. S.. Geoestatística aplicada na avaliação da qualidade de dados

geoespaciais. Dissertação de Mestrado em Informações Espaciais. Universidade

Federal de Viçosa - UFV. Viçosa, MG, 2013.

alex.santos@ibge.gov.brwww.ibge.gov.br

Brazilian Institute of Geography and Statistics – IBGEMission: "To portray Brazil by providing the information required for the understanding

of its reality and the exercise of citizenship“.

Thank you!Xièxiè!

Alex da Silva Santos (Mr)