5 Marzo 2007 EMERGING METHODOLOGIES OF CONTINUOUS USE OF REGISTERS AND GEOCODED DATABASES IN THE ITALIAN POPULATION AND HOUSING CENSUS Fabio Crescenzi, Methods and Techniques for Censuses Istat (National Institute of Statistics), Italy International Seminar on Population and Housing Censuses: Beyond the 2010 Round Seoul, November 2012

Pressure for a greater use of administrative sources the need of frequently updated and georeferenced data + Operational complexity of decennial census = Pressure for a greater use of administrative sources Register based census Combined census

The 2011 Combined Census mail out using Municipal Population Registers (LAC), multi-mode data collection, field correction of coverage errors, short form/long form strategy in Municipalities with more than inhabitants.

Multi-mode data collection Online: To fill the questionnaire online, using the provided password (33,4%) Post office: to Return the paper questionnaire to any post office in Italy (22,6%) Municipal Centre: to return the paper questionnaire to one of the Municipal Collection Centres (31,7%) Enumerator: to return the paper questionnaire to enumerator (12,3 %)

Web Monitoring and Enumerators field recovery Web census management system. A web management system was devoted to the census field work (SGR - survey management system). Enumerators recovery non-responders unregistered individuals The number of enumerators dropped from in 2001 to in 2011 (-37%).

Maximum use of administrative and statistical data sources + Rolling Sample Surveys to correct coverage errors and to supplement data = Georeferenced census data every year

The quality of the sources Quality errors (Accuracy, Completeness, Update status, Coherence among sources, Accuracy of Geocoding) are a burden For the use of administrative sources for census purposes

The equilibrium of Archimedes

ARCHIMEDE, Archive of Economic and Demo-social Micro-data Infrastructure that will provide anonymised micro data to Public Administrations, researchers and users. Geo-referenced data up to the enumeration area level Longitudinal data to study the evolution over time

C-sample and D-sample survey Georeferencing Integrated System of microdata strength of care = max Sources on individuals and households errors The force generated by the care of errors (Archimede Burning Mirrors)

Other Administrative Sources Integrated Microdata Repository Information System on Population Municipal Register Continuous Census of Households Individuals Demographic and Social Surveys ARCHIMEDE Infrastructure of Georeferenced microdata of individuals and households D-sample C-sample Georeferencing Data of census survey

Give me a fulcrum and I will move the world... (Archimede)

The leverage effect of continuous census The cumulation of data collected by administrative sources and cared by sample annual survey can Produce data capable of satisfying the needs of a decennial census and the annual needs of users

Searching the best leverage Maximising the use of local administrative sources Increasing the care of errors Looking for the best design of sample surveys

In the rotation movement the revolution

C-sample and D-sample to correct coverage errors and to supplement data The waves of two different sample surveys (the C-sample and the D- sample survey) will be used in crucial stages of a continuous process designed to achieve, separately, the two main goals of census operations: i) correct the counting of usual residents to produce the key data on demographic structure of population and households; ii) supplement socio economic data to produce census data hypercubes.

Georeferencing and mapping A key role is given to the ANSC, the georeferenced national register of streets and addresses Census mapping has to be made consistent with the requirements of a continuous census

C-sample Starting date 2016 Questionnaire Short – only data to count persons and households Tecnique Paperless CAPI Sampling design Capture Recapture on about households per year Monitoring WEB (SGR)

D-sample Sampling design Two stage – About households per year Questionnaire Long Technique Paperless: CAWI and CAPI Monitoring WEB (SGR)

D-sample. Plan of data accumulations by output area size Output area size (inhab.) Number of years Pooling Interval Central year > t t t, (t-1), (t-2)(t-1) < t, (t-1), (t-2), (t-3), (t-4)(t-2)

D-sample. Dissemination Starting Plan