OVERVIEW OF ARCHIVING OF MICRODATA SILAS M. MULWA Kenya National Bureau of Statistics United Nations Regional Seminar on Census Data Archiving for Africa Addis Ababa, rd 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-data Micro-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

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