Metadata to Support the Survey Life Cycle

Alice Born, Statistics CanadaJoint UNECE/Eurostat/OECDWork Session on Statistical Metadata(METIS)Geneva, April 3-5, 2006

Outline

• Description of STC’s Integrated Metadatabase (IMDB)

• Common metatdata set for a survey life cycle

• Tools for entering metadata

• Time travel – versioning rules

• Complete model

Corporate metadata at Statistics Canada

• Integrated Metadatabase (IMDB)– Collection of information about each of

Statistics Canada’s 560+ current surveys– Aimed at helping users interpret statistical

data• Survey description• Survey instrument• Methodology• Data accuracy• Variables, classifications

What is the IMDB based on?

• ISO 11179 Specification and Standardization of Data Elements

• Corporate Metadata Repository (CMR) – USBC (D. Gillman)

• Extension of ANSI X3.285 for the management of statistical information (American National Standards Institute metamodel)

Surveys - definition

• Metadata in the IMDB is organized around the survey entity

• Refers to collection, compilation and publication of data measuring characteristics of a population

• Three types of surveys:• Direct • Administrative• Derived

Statistical Activities

• Group of surveys that share common feature, common explanatory text

• E.g., System of National Accounts:

The Canadian System of National Accounts (CSNA) provides a conceptually integrated framework of statistics and analysis for studying the state and behaviour of the Canadian economy. The accounts are centered on the measurement of activities associated with production of goods and services, the sales of goods and services in final markets, the supporting financial transactions and the resulting wealth positions.

Regions

Organization

Contact

Documentation

Identification

Time Frame

Keyword

Theme

Survey

Universe

Frame

Survey instance

Instrument

Question

Data file

Methodology

Instrument designSamplingData sourceError detectionImputationEstimationQuality evaluationDisclosure controlRevisions and seasonal adjustmentData accuracy

Data Element

Data Element Concept

Object Class

Property

Formula

Conceptual Domain

Value Domain

Stewardship

Identification

Classification

Statistical Activity

Common metadata set for survey life cycle

Statistical activity

Survey (direct, administrative, derived) Target population (population, statistical unit)

Survey instance (each survey process)

Collection instrument Methodology

Data accuracy

Documentation

Data file

(Data elements, value domains)

Common metadata set for survey life cycle

MethodologyInstrument designSampling Collection methodError detectionImputation EstimationQuality evaluationDisclosure controlRevisions and seasonal adjustment

Common metadata set for survey life cycle

Survey

Survey Instance- questionnaires- variables (DE)- methodology- data accuracy

Common metadata set for survey life cycle

Survey Instruments

Common metadata set for survey life cycle

Data elements

Common metadata set for survey life cycle

Methodology

Target population

Instrument design

Tools for loading metadata into IMDB

Statistical Activity - Identification Tab

Statistical Activity and Survey- DescriptionTab

Survey Instance (cycle) – Times Frames

Data sources – Description

Versioning (time-travel)

• Metadata change over time – each survey instance, survey or statistical activity

• Rules for revisions and versioning of administered items

• Three functions:– Create– Update– Version

Versioning (time-travel)

Survey:• Changes to mandate or subject of survey – new survey

(new IMDB record and new SDDS number)• Changes to characteristics of surveys – new version of

survey

Survey instance:• Each reference period – new version of the instance

– Now it coincides with release of data in the Daily– Demand for the new instance version to coincide with collection

start dates – Central link to versioning of other administered items

(instrument, methodology and data file)

Versioning (time-travel)

Target population:• Changes result in a new version of the survey

and target population

Statistical activity:• Changes to program mandate or structure

(addition or removal of surveys) results in new version of statistical activity

StatisticalActivity

Survey

Survey Instance

Data File

Methodology

Instrument

Applications/Software

Products(COR)

Data elements

Frame and Sample

Target population