A census is the procedure of systematically acquiring and recording
information about the members of a given population. The term is used
mostly in connection with national population and housing censuses;
other common censuses include agriculture, business, and traffic
censuses. The
Contents 1 Sampling
2 Residence definitions
3 Enumeration strategies
4 Technology
5
6.1
7 Privacy 8 Historical censuses 8.1 Egypt 8.2 Ancient Greece 8.3 Ancient Israel 8.4 China 8.5 India 8.6 Rome 8.7 Rashidun and Umayyad Caliphates 8.8 Medieval Europe 8.9 Inca Empire 8.10 Spanish Empire 9 World population estimates 10 Modern implementation 11 See also 12 Notes 13 References 14 External links Sampling[edit]
A census is often construed as the opposite of a sample as its intent
is to count everyone in a population rather than a fraction. However,
population censuses rely on a sampling frame to count the population.
This is the only way to be sure that everyone has been included as
otherwise those not responding would not be followed up on and
individuals could be missed. The fundamental premise of a census is
that the population is not known and a new estimate is to be made by
the analysis of primary data. The use of a sampling frame is
counterintuitive as it suggests that the population size is already
known. However, a census is also used to collect attribute data on the
individuals in the nation. This process of sampling marks the
difference between historical census, which was a house to house
process or the product of an imperial decree, and the modern
statistical project. The sampling frame used by census is almost
always an address register. Thus it is not known if there is anyone
resident or how many people there are in each household. Depending on
the mode of enumeration, a form is sent to the householder, an
enumerator calls, or administrative records for the dwelling are
accessed. As a preliminary to the dispatch of forms, census workers
will check any address problems on the ground. While it may seem
straightforward to use the postal service file for this purpose, this
can be out of date and some dwellings may contain a number of
independent households. A particular problem is what are termed
'communal establishments' which category includes student residences,
religious orders, homes for the elderly, people in prisons etc. As
these are not easily enumerated by a single householder, they are
often treated differently and visited by special teams of census
workers to ensure they are classified appropriately.
Residence definitions[edit]
Individuals are normally counted within households and information is
typically collected about the household structure and the housing. For
this reason international documents refer to censuses of population
and housing. Normally the census response is made by a household,
indicating details of individuals resident there. An important aspect
of census enumerations is determining which individuals can be counted
from which cannot be counted. Broadly, three definitions can be used:
de facto residence; de jure residence; and, permanent residence. This
is important to consider individuals who have multiple or temporary
addresses. Every person should be identified uniquely as resident in
one place but where they happen to be on
Enumerator conducting a survey using a mobile phone based questionnaire in rural Zimbabwe. Triple system enumeration has been proposed as an improvement as it
would allow evaluation of the statistical dependence of pairs of
sources. However, as the matching process is the most difficult aspect
of census estimation this has never been implemented for a national
enumeration. It would also be difficult to identify three different
sources that were sufficiently different to make the triple system
effort worthwhile. The DSE approach has another weakness in that it
assumes there is no person counted twice (over count). In de facto
residence definitions this would not be a problem but in de jure
definitions individuals risk being recorded on more than one form
leading to double counting. A particular problem here are students who
often have a term time and family address.
Several countries have used a system which is known as short form/long
form.[10] This is a sampling strategy which randomly chooses a
proportion of people to send a more detailed questionnaire to (the
long form). Everyone receives the short form questions. Thereby more
data are collected but not imposing a burden on the whole population.
This also reduces the burden on the statistical office. Indeed, in the
UK all residents were required to fill in the whole form but only a
10% sample were coded and analysed in detail, until 2001.[11] New
technology means that all data are now scanned and processed. Recently
there has been controversy in Canada about the cessation of the long
form with the head,
League of Nations and International Statistical Institute estimates of the world population in 1929 Modern implementation[edit] Main article: Population and housing censuses by country Nigerian leaders cannot put a number on the amount of Nigerian women and girls that have gone missing. Nigeria has never had a credible, successful census. —Olúfémi Táíwò, professor of Africana studies at Cornell University[42] See also[edit] Languages in censuses Liber Censuum Race and ethnicity in censuses Social research Notes[edit] ^
References[edit] Alterman, Hyman, (1969). Counting People: The
External links[edit] Wikimedia Commons has media related to Census. "Census". Encyclopædia Britannica. 5 (11th ed.). 1911.
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