Censuses (cont.)

United Nation’s definition of a census:

"The total process of collecting, compiling, analysing, and publishing or otherwise disseminating demographic, economic and social data pertaining to all persons in a country or in a well-delineated part of a country at a specified time."

There are several aspects of this definition that are worth emphasising.

  1. This definition refers to the “total process”. It not sufficient to simply collect and collate information in a census. The data collected must also be analysed, published and disseminated.
  2. The scope of a census encompasses demographic, economic and social data. Thus a census will often seek to collect more than just a simple headcount of the population. The reasons for this relates to the logistics of the exercise: if one is going to try to individually enumerate each person in a population, the marginal cost of collecting additional information (on income, education, housing etc.) is low, although will lead to an increase in the length of (and hence time taken to complete) the census instrument. The implications of this are discussed in a later section. Often the census is referred to as a Population and Housing Census to emphasise the broader ambitions of the census.
  3. The census aims for universality, that is, to enumerate all people in a population. This is less simple than it may seem. The problems associated with attempting to define and count “all the people within a population” will be discussed in the following pages.
  4. The census aims for simultaneity - it seeks to produce a snapshot of the population at a point in time. With the exception of very small and compact populations, it is usually impossible to actually enumerate a population on a single date. In many countries, census enumeration takes place over a number of weeks. To this end, censuses usually have a defined ‘census date’ for which responses are elicited, regardless of when the questions are actually put to the respondent. Households are asked to recall the people who slept in the house or who were usual members of the household on the census date. Births and deaths that occurred between the census date and the date of enumeration (when the household was actually counted) should be omitted.