DEMANDS FOR AND PROVISION OF CENSUS MICRO DATA: THE SRI LANKAN EXPERIENCE

Vasana Jayakody

Department of Census and Statistics

Sri Lanka

The power of Micro data

Overview Introduction

Sri Lankan national statistical system Legal authority Censuses of Population and Housing

Release of micro data Current practice Issues in releasing Census micro data

Archiving micro data Way forward…

Introduction – National Statistical System

A centralized system DCS has the co-ordinatory and technical

supervisory authority Legal authority is vested with the DCSAmong DCS responsibilities are;

Establishment and maintenance of statistical standards, coding and classification schemes

Provision of trained statistical cadres required by the national statistical system

Introduction – National Statistical System

Before gaining independence in 1948 Statistics were compiled as by-products of

administrative records by individual departments or Collected by separate Census Units/ Statistical

branches with little or no coordination After 1948

The Department of Census and Statistics (DCS) was formed.

The official statistical system began to develop in a co-ordinated and systematic manner to meet the growing demand for comprehensive and reliable statistics by planners and policy makers.

1951 and afterwards The then Prime Minister issued a directive

in 1951 that it is the responsibility of DCS to provide all statistical information required by government departments.

Statistical branches were established in key ministries and government departments.

Statistical units were set up in all 25 districts throughout the country.

Introduction – National Statistical System

Legal authority

2 Ordinances under which the DCS collects data. Census Ordinance Statistics Ordinance

Established to secure the reliability and thereby the usefulness of statistics by ensuring the protection of the privacy of the respondents.

Legal authority – Census Ordinance First in 1868 – under English Law Repealed in 1900 (drafted on the lines of the

Indian Census Act). This has substantially became the basis for Census taking in Sri Lanka with minor amendments in subsequent censuses.

The Census Ordinance casts an obligation on the part of the respondents to answer all questions asked at the Census, and at the same time safeguards the respondents by causing any information collected at a census, to be inadmissible as evidence in a court of law.

Legal authority - Statistics Ordinance Was enacted in 1935 and amended in 1955. Provides for the establishment of an official

bureau of Statistics. Provides legal sanction for the DG of Census to

collect statistical information. Safeguards the confidentiality of information

provided by the respondent. Prevents the disclosure or arrangement of data

to facilitate the identification of any particulars as being information related to any individual persons or business, in any report, summary of statistics or other publications prepared based on the data collected under the Statistics ordinance.

Censuses of Population and Housing

First scientific Population Census in 1871. Usually in every 10 years with certain exceptions.

No census in 1991 due to the disturbances prevailed in the Northern/Eastern parts of the country.

Only 18 (out of 25) districts were covered in 2001.

CPH2012 is the 14th decennial Census. Special significance as the first Census to cover

the entire country since 1981 (after 31 years).

CPH2012

Traditional Census which was conducted in 3 main stages. New technologies were used at all possible stages.

Mapping Operation Use of satellite images, GPS to demarcate and draw Census Block Maps.

Listing Operation Buildings in all 65,000 CBs were labeled, numbered and listed and the “Master Register of Census Blocks”, the Census Monitoring System was prepared.

Census EnumerationWas conducted between 27 February – 20 March 2012. Online Census on pilot basis (in selected condominiums in

Colombo)

New technologies – Post enumeration Data Processing

Data capture using OMR, ICR Computer Assisted Coding of Occupation

and Industry Imputations

Data Dissemination Interactive visualizations (QuickStats) Interactive online databases (REDATAM)

Release of micro data – current practices Dissemination of census data in the form of

micro data poses challenges as the DCS is bound to safeguard the right to privacy of the respondents and any breach of privacy would lead to loss of trust of the respondents leading to non-cooperation in future census taking exercises.

DCS, therefore, has been cautious in disseminating data in the form of micro data and has formulated its policy on micro data dissemination with strict adherence to the statistics ordinance.

Release of micro data – current practices Micro data of Censuses is not released. Micro data of sample surveys are released free

of charge to selected users (Requests of only government institutes, recognized universities, students engaged in higher education, selected international agencies are entertained).

Should submit the study/project proposal. Only 25% of the data file at the first stage and

the full data file is considered after reviewing the draft report prepared on the 25% sample.

Should sign an agreement assuring confidentiality when handling/storing micro data.

LankaDatta – the National Data Archive LankaDatta, the National Micro data Archive, was

started in 2008. The repository for non official datasets as well. Technical and financial assistance - Accelerated Data

Program from the World Bank and PARIS21 Tools/ guidelines was provided by the International

Household Survey Network. Data Documentation Initiative (DDI) metadata standard is used in LankaDatta.

The DCS is responsible of acquisition, documentation, anonymisation, dissemination and preservation of micro data and related metadata.

Way forward….

Currently investigating the possibilities of improving the Census micro data dissemination methodology.

Options being investigated Licensed census micro data files for bona

fide users Data enclave in the DCS head office Remote data access – REDATAM+SP

Way forward….

Issues that are looked into; Whom should the Licensed files be made

available to Appropriate sample size for release Who can access data at the Data Enclave Should current annonymization methods be

changed Timing of micro data release Additional costs and how they are recovered Possible logistic issues

Thank you………