OVERVIEW OF ARCHIVING OF MICRODATA

SILAS M. MULWAKenya National Bureau of Statistics

United Nations Regional Seminar on Census Data Archiving for Africa Addis Ababa, 20-23rd September 2011

OUTLINE

Definition of Micro-data Why disseminate Micro-data? Acquisition and preparation of data Tools for Archiving of Micro-data Dissemination of micro-data Risks of disseminating microdata

Definition of Micro-dataMicro-data: are defined as files of records

pertaining to individual respondent units (mainly through household interviews).

Micro-data files for dissemination purposes may differ from those used within the KNBS;

all direct and indirect identifiers have may be removed through various anonymization processes

Micro-data as opposed to Macro-data contains records pertaining to individual firms/institutions or aggregated records at national or county levels.

Why disseminate Data use?

To Broaden data use and reuse To add value to data bringing subject

matter knowledge to data analysis To get feedback from the data users,

which could be used to improve data quality and also improve data collection in the future.

5

Foster diversity and deepen the quality of data analysis thereby extracting more information from the data.

Reduce duplication in data collection Leveraging funding for statistics Complying with a contractual or legal

obligation e.t.c.

Why disseminate Data use? Cont’

Acquisition and preparation Questionnaire Design and Sampling

design Data collection Data is coded after collection Data Capture Draft Data is archived using tools Data editing and derived variables

created Edited set is archived followed by

anonymization

Tools for Archiving of Micro-data

1.Data archiving has various components these includes;

Data documentation Cataloguing Data dissemination Anonymization Preservation. A combination of tools are required so as to construct all the

components.

 

Archiving tools cont’d

KNBS has used both standard and non standard tools for data archiving.

IHSN micro-data management Toolkit – It is a standard kit for documenting datasets in compliance with Data Documentation Initiative (DDI) and the Dublin Core Standards.

KNBS has not used the toolkit to document census micro-data but 7 survey datasets have been documented and archived using this tool.

Archiving tools cont’d

NADA Is DDI standard compliant for archiving and

dissemination. KNBS has not used the tool but it is building capacity on NADA

Redatam – IMIS (integrated mult-sectoral information system)

KNBS has used IMIS to store 1989, 1999 Census Microdata. Mainly it is used to query information and is web-based

Archiving tools cont’d

CSPRO and ICADE: Not for archiving but for capturing and

storage of census-data Micro-data, there is very little documentation apart from providing ASCII file structures

DISEMINATION OF MICRO-DATA

Due to Technological advancement in ICT and increased demand for data, KNBS is changing the way of accessing and disseminating information to the users.

Traditionally KNBS has been using publications, seminars and workshops to release and disseminate survey and census data.

Census micro-data can be accessed and queried using IMIS.

DISEMINATION OF MICRO-DATA cont’d

Offline Dissemination CDs, DVDs are used for data distribution Microdata after anonymisation process. Only 5% of Census data can be given to

users on special request.

Mobile Dissemination: It was used to disseminate 2009 population census results.

Risks of disseminating microdata

Disclosure: This is the risk of re-identification of particular

individuals and is one of biggest challenges. It can lead to violation of laws, lose of trust by

the public and compromise quality

Controversy of results: User may obtain different results from the one

published by KNBS resulting to controversy and criticism

END OF PRESENTATION