Organised byOrganised byUnited Nations Statistics Division (UNSD) in United Nations Statistics Division (UNSD) in

conjunction with the National Bureau of conjunction with the National Bureau of statistics (NBS)statistics (NBS)

Dar es Salaam , Tanzania, 9 – 13 June 2008Dar es Salaam , Tanzania, 9 – 13 June 2008

Workshop on Census Data Processing: Workshop on Census Data Processing: Contemporary Technologies for census Contemporary Technologies for census

Data Capture and Data EditingData Capture and Data Editing

Country ReportCountry Report

Presented byPresented by

Mrs. N.GujadhurMrs. N.Gujadhur

Central Statistics OfficeCentral Statistics OfficeMauritiusMauritius

June 2008June 2008

Islands of Mauritius and Islands of Mauritius and RodriguesRodrigues• Capital: Port LouisCapital: Port Louis

• Population : 1.26 mnPopulation : 1.26 mn

• Population growth rate: 0.6%Population growth rate: 0.6%

• Area: 2,040 km2Area: 2,040 km2

• Population density: 616 Population density: 616 persons/km2 persons/km2

• Monetary unit: MRupees Monetary unit: MRupees

• Literacy rate : 85%Literacy rate : 85%

• Languages: English & FrenchLanguages: English & French

• Census taking in MauritiusCensus taking in Mauritius

• Core topics covered in 2000 HPCCore topics covered in 2000 HPC

• Editing and codingEditing and coding

• Data ProcessingData Processing

• Data Capture OutsourcingData Capture Outsourcing

• Data Validation & TabulationData Validation & Tabulation

• ProblemsProblems

OutlineOutline

• 1st complete Census in the Island of Mauritius was 1st complete Census in the Island of Mauritius was undertaken in 1735undertaken in 1735

• Since then, censuses have been taken in 1846, 1851 Since then, censuses have been taken in 1846, 1851 and every 10 years up to 1931.and every 10 years up to 1931.

• After the 2nd World War, the ten-yearly programme After the 2nd World War, the ten-yearly programme was resumed and Housing and Population censuses was resumed and Housing and Population censuses were undertaken in:were undertaken in:

1952, 1962, 1972, 1952, 1962, 1972, 1983, 1990 and 2000 1983, 1990 and 2000

• Next census => 2010Next census => 2010

Census taking in Mauritius Census taking in Mauritius

Census Organisation/DocumentationCensus Organisation/Documentation

The 2000 Housing & Population Census (HPC) was The 2000 Housing & Population Census (HPC) was conducted in the Island of Mauritius, Rodrigues and conducted in the Island of Mauritius, Rodrigues and Agalega.Agalega.

• Enumeration forms, Instructions & codebooks were the Enumeration forms, Instructions & codebooks were the main source of documentation used during the HPC. main source of documentation used during the HPC.

• 1st round - Housing Census1st round - Housing Census– Chief Enumerators enumerated all buildings, Chief Enumerators enumerated all buildings,

housing units, households, commercial housing units, households, commercial establishments, hotels, institutions etc.establishments, hotels, institutions etc.

– Enumeration Books, each containing 25 Housing Enumeration Books, each containing 25 Housing forms. forms.

• 2nd round - Population Census 2nd round - Population Census

– Enumerators enumerated all persons present on Enumerators enumerated all persons present on census night as well as usual residents who were census night as well as usual residents who were away on census night.away on census night.

– A Population questionnaire was used to collect A Population questionnaire was used to collect information.information.

• Details instructions were provided to Supervisors, Chief Details instructions were provided to Supervisors, Chief Enumerators and Enumerators. Enumerators and Enumerators.

• A Census Guide and Instructions was also given to A Census Guide and Instructions was also given to head of household for completing the Population head of household for completing the Population questionnaire.questionnaire.

Census Organisation/Documentation Census Organisation/Documentation (Cont’d)(Cont’d)

The Core Topics covered in the 2000 Housing Census were:The Core Topics covered in the 2000 Housing Census were: • Type of living QuartersType of living Quarters• Location of living quartersLocation of living quarters• Occupancy status Occupancy status • Type of Ownership Type of Ownership • Numbers of rooms Numbers of rooms • Water supply system Water supply system • Toilet Toilet • Sewage disposalSewage disposal• Bathing facilities Bathing facilities

Principles and Recommendations for Principles and Recommendations for Population and Housing CensusesPopulation and Housing Censuses

Principles and Recommendations for Principles and Recommendations for Population and Housing Censuses (Cont’d)Population and Housing Censuses (Cont’d)

Core Topics for Housing Census Core Topics for Housing Census • Availability of kitchenAvailability of kitchen• Fuel used for cookingFuel used for cooking• Type of lighting/Use of electricity Type of lighting/Use of electricity • Solid waste disposalSolid waste disposal• Number of OccupantsNumber of Occupants• Type of tenureType of tenure• Type of buildingType of building• Construction material of outer walls Construction material of outer walls

• The recommended core topics covered in the 2000 The recommended core topics covered in the 2000 Population census were:Population census were:

Geographical and Internal Migration Geographical and Internal Migration characteristicscharacteristics- Place of usual residence and place where - Place of usual residence and place where present at time of censuspresent at time of census

International Migration characteristicsInternational Migration characteristics - Citizenship- Citizenship Household and Family characteristicsHousehold and Family characteristics

- Relationship to head - Relationship to head Demographic and Social characteristicsDemographic and Social characteristics

- Sex, age and Marital status- Sex, age and Marital status

Principles and Recommendations for Principles and Recommendations for Population and Housing Censuses (cont’d)Population and Housing Censuses (cont’d)

Principles and Recommendations for Principles and Recommendations for Population and Housing Censuses (Cont’d)Population and Housing Censuses (Cont’d)

Fertility and Mortality characteristicsFertility and Mortality characteristics - Children ever born- Children ever born Educational characteristicsEducational characteristics

- Literacy, School Attendance and School - Literacy, School Attendance and School AttainmentAttainment

Economic characteristicsEconomic characteristics - Activity Status, Occupation, Industry and - Activity Status, Occupation, Industry and

Status in EmploymentStatus in Employment Disability characteristicsDisability characteristics - Disability status- Disability status

Editing and Coding – Housing CensusEditing and Coding – Housing Census

• Housing Census questionnaires started during the 2nd Housing Census questionnaires started during the 2nd week of March 2000 and was completed during the week of March 2000 and was completed during the 1st week of May.1st week of May.

• 30 editors and coders and 3 supervisors and about 30 editors and coders and 3 supervisors and about 310,000 Housing Census forms were edited and 310,000 Housing Census forms were edited and coded. coded.

• ½ day training for the editors and coders. Training ½ day training for the editors and coders. Training was an on going process. Short briefing sessions was an on going process. Short briefing sessions were conducted as and when needed. were conducted as and when needed.

Editing and coding was done manually. Editing and coding was done manually.

• (i) Verified that geographical identifiers on the (i) Verified that geographical identifiers on the cover of booklets making the EA batch were the cover of booklets making the EA batch were the same.same.

• (ii) Consistency checks of block numbers, building (ii) Consistency checks of block numbers, building numbers within blocks as well as the housing units numbers within blocks as well as the housing units within buildings were then performed.within buildings were then performed.

Editing and Coding – Housing census Editing and Coding – Housing census (cont’d)(cont’d)

• (iii) Some examples of the consistency checks(iii) Some examples of the consistency checks

- if “ Roof” = concrete slab, then “ Walls”- if “ Roof” = concrete slab, then “ Walls”should also be stone, concrete, should also be stone, concrete, concrete concrete blocks, and bricks.blocks, and bricks.

- if Bathing Facilities is marked, then “HU3 – - if Bathing Facilities is marked, then “HU3 – Water Supply” should be Piped water Water Supply” should be Piped water inside housing unit.inside housing unit.

- Ensure that the no. of Male and Female in - Ensure that the no. of Male and Female in column “No. of persons” add up to column “No. of persons” add up to

Total.Total.

- if tenure =Owner or free, monthly rent - if tenure =Owner or free, monthly rent should should be zerobe zero

Editing and Coding – Housing census Editing and Coding – Housing census (cont’d)(cont’d)

Editing and Coding – Population CensusEditing and Coding – Population Census

• Population Census questionnaires started August Population Census questionnaires started August 2000 and was completed in May 2001.2000 and was completed in May 2001.

• 50 editors and coders were involved and about 50 editors and coders were involved and about 300,000 Census forms were edited and coded. 300,000 Census forms were edited and coded.

• ½ day training for the editors and coders. Training ½ day training for the editors and coders. Training was an on going process. Short briefing sessions was an on going process. Short briefing sessions were conducted as and when needed. were conducted as and when needed.

• Editing & coding of the Population Census forms was Editing & coding of the Population Census forms was more complex and time-consuming than that of the more complex and time-consuming than that of the Housing Census forms Housing Census forms

– Verification of the EA batches consisted of Verification of the EA batches consisted of checking that all census forms in a given batch,checking that all census forms in a given batch,

– appropriate geographical codes were inserted on appropriate geographical codes were inserted on unaddressed forms,unaddressed forms,

– consistency checking and editing of the individual consistency checking and editing of the individual forms according to “2000 Population census - forms according to “2000 Population census - Editing & Coding Instructions”.Editing & Coding Instructions”.

Editing and Coding – Population Census Editing and Coding – Population Census (cont’d)(cont’d)

• Some example of the checksSome example of the checks Check that there is one and only one head in every Check that there is one and only one head in every

household. household. Check the number of family nucleiCheck the number of family nuclei Check for possible inconsistency between name, Check for possible inconsistency between name,

relationship and sex for every person.relationship and sex for every person. Check that age is consistent with date of birth. Check that age is consistent with date of birth. Check marital status with age.Check marital status with age. Check if age at first marriage is > 10 yearsCheck if age at first marriage is > 10 years Check number of children ever born with age and sex.Check number of children ever born with age and sex. Check education and highest qualification with age.Check education and highest qualification with age. Check the internal consistency of the information on Check the internal consistency of the information on

economic activity.economic activity.

Editing and Coding – Population Census Editing and Coding – Population Census (cont’d)(cont’d)

• Coding of Housing & Population CensusCoding of Housing & Population Census

International Classifications adapted to the countryInternational Classifications adapted to the countryNational Classification of Occupations (Based on National Classification of Occupations (Based on

ISCO 88)ISCO 88) National Standard Industrial Classification of National Standard Industrial Classification of

Economic Activities (Based on ISIC Rev. 3, 1990)Economic Activities (Based on ISIC Rev. 3, 1990)Codes for Vocational/technical/tertiary Codes for Vocational/technical/tertiary

qualification (Adapted from ISCED)qualification (Adapted from ISCED) Locality codes and country codes Locality codes and country codes

Editing and Coding – Population CensusEditing and Coding – Population Census

Data ProcessingData Processing

• The processing of the HPC data were done along the The processing of the HPC data were done along the same lines, although the various operations involved same lines, although the various operations involved in the processing were somewhat more complex for in the processing were somewhat more complex for the PC than for the HC.the PC than for the HC.

Data capture;Data capture;Data validation and updating of data files;Data validation and updating of data files;Production of address labels from Housing Census Production of address labels from Housing Census

files and printing of labels;files and printing of labels;Tabulation.Tabulation.

• Data capture for the 2000 H&PC was outsourced to Data capture for the 2000 H&PC was outsourced to another government organisationanother government organisation

- The Central Statistics Office (CSO) does not - The Central Statistics Office (CSO) does not have its own full-fledged IT department and have its own full-fledged IT department and

- personnel capable of undertaking data - personnel capable of undertaking data capture activities. capture activities.

• Data entry was done by operators of the Central Data entry was done by operators of the Central Information Systems Division (CISD) of the Ministry of Information Systems Division (CISD) of the Ministry of Information Technology and Telecommunications.Information Technology and Telecommunications.

Data Capture – OutsourcingData Capture – Outsourcing

• The data entry staff was composed of 28 operators and The data entry staff was composed of 28 operators and 5 supervisors.5 supervisors.

• The Data Entry operators were given a short training The Data Entry operators were given a short training before starting the work, and short session were before starting the work, and short session were conducted as and when needed. conducted as and when needed.

• Coded questionnaires were sent to the CISD in EA Coded questionnaires were sent to the CISD in EA Batches for data capture. Batches for data capture.

All Housing and Population Census questionnaires were All Housing and Population Census questionnaires were verified; i.e. Double entry. verified; i.e. Double entry.

Data Capture – Outsourcing (cont’d)Data Capture – Outsourcing (cont’d)

• Software used was IMPS 4.1 (Integrated Microcomputer Software used was IMPS 4.1 (Integrated Microcomputer Processing System) of the International Programs Center Processing System) of the International Programs Center of the US Bureau of the Census. of the US Bureau of the Census.

• The data entry exercise of about 310,000 HC forms The data entry exercise of about 310,000 HC forms started in March 2000 and was completed in May 2000.started in March 2000 and was completed in May 2000.

• Names and addresses of head of households were used as Names and addresses of head of households were used as a frame for the Population Census enumeration. a frame for the Population Census enumeration.

Data Capture – Housing CensusData Capture – Housing Census

• Data capture for the Population Census started in Data capture for the Population Census started in September 2000 and was completed in July 2001. September 2000 and was completed in July 2001.

• Data for around 300,000 Population Census forms Data for around 300,000 Population Census forms containing about 1,200,000 records were keyed in containing about 1,200,000 records were keyed in during that period. during that period.

• The CISD had recourse to extensive after-office work The CISD had recourse to extensive after-office work to complete the data entry exercise within reasonable to complete the data entry exercise within reasonable time limits.time limits.

Data Capture – Population CensusData Capture – Population Census

Data validationData validation• A validation programme was run to identify records A validation programme was run to identify records

with errors.with errors.

• Listings of these records were produced; relevant census Listings of these records were produced; relevant census forms were retrieved and corrections were made forms were retrieved and corrections were made accordingly.accordingly.

• Data files were updated. Data files were updated.

• Once validation of all data files was completed, the data Once validation of all data files was completed, the data files were concatenated to the country level.files were concatenated to the country level.

• Tabulation was done using the CENTS module of Tabulation was done using the CENTS module of IMPS. IMPS.

• A preliminary set of publication tables was produced A preliminary set of publication tables was produced using the country data file. using the country data file.

• A list of relevant edit specifications was drawn and A list of relevant edit specifications was drawn and incorporated in a CONCOR programme to remove incorporated in a CONCOR programme to remove the inconsistencies from the tabulated data. the inconsistencies from the tabulated data.

• Table reports for Housing Census were completed in Table reports for Housing Census were completed in October 2000 and for Population Census in October October 2000 and for Population Census in October 2001.2001.

• All publications are posted on the office website at All publications are posted on the office website at the following address: the following address: http://http://statsmauritius.gov.mustatsmauritius.gov.mu..

TabulationTabulation

Problems encountered during the 2000 HPCProblems encountered during the 2000 HPC

• Problems of shortage of staff were met at various Problems of shortage of staff were met at various stages of the census operation, causing delays on the stages of the census operation, causing delays on the time schedule. ( Fieldstaff, editors and coders, data time schedule. ( Fieldstaff, editors and coders, data entry operators)entry operators)

• As regards data capture, this was done by the Central As regards data capture, this was done by the Central Information System Division of the Ministry of IT Information System Division of the Ministry of IT and very often the census work was not given priority and very often the census work was not given priority over other work thus resulting in delays.over other work thus resulting in delays.

Thank youThank you