Population density and urbanization
|Concepts and definitions|
|Locality (paras. 2.78.- 2.80.)|
|Urban and rural (paras. 2.81.- 2.88.)|
|Locality (paras. 96.- 99.)|
|Urban and rural (paras. 100.- 103.)|
For census purposes, a locality should be defined as a distinct population cluster (also designated as inhabited place, populated centre, settlement and so forth) in which the inhabitants live in neighbouring sets of living quarters and that has a name or a locally recognized status. It thus includes fishing hamlets, mining camps, ranches, farms, market towns, villages, towns, cities and many other population clusters that meet the criteria specified above. Any departure from this definition should be explained in the census report as an aid to the interpretation of the data.
Localities as defined above should not be confused with the smallest civil divisions of a country. In some cases, the two may coincide. In others, however, even the smallest civil division may contain two or more localities. On the other hand, some large cities or towns may contain two or more civil divisions, which should be considered as segments of a single locality rather than separate localities.
A large locality of a country (that is to say, a city or a town) is often part of an urban agglomeration, which comprises the city or town proper and also the suburban fringe or thickly settled territory lying outside, but adjacent to, its boundaries. The urban agglomeration is therefore not identical with the locality but is an additional geographical unit, which may include more than one locality. In some cases, a single large urban agglomeration may comprise several cities or towns and their suburban fringes. The components of such large agglom¬erations should be specified in the census results.
Because of national differences in the characteristics that distinguish urban from rural areas, the distinction between the urban and the rural population is not yet amenable to a single definition that would be applicable to all countries or, for the most part, even to the countries within a region. Where there are no regional recommendations on the matter, countries must establish their own definitions in accordance with their own needs.
The traditional distinction between urban and rural areas within a country has been based on the assumption that urban areas, no matter how they are defined, provide a different way of life and usually a higher standard of living than are found in rural areas. In many industrialized countries, this distinction has become blurred and the principal difference between urban and rural areas in terms of the circumstances of living tends to be a matter of the degree of concentration of population. Although the differences between urban and rural ways of life and standards of living remain significant in developing countries, rapid urbanization in these countries has created a great need for information related to different sizes of urban areas.
Hence, although the traditional urban-rural dichotomy is still needed, classification by size of locality can usefully supplement the dichotomy or even replace it where the major concern is with characteristics related only to density along the continuum from the most sparsely settled areas to the most densely built-up localities.
Density of settlement may not, however, be a sufficient criterion in many countries, particularly where there are large localities that are still characterized by a truly rural way of life. Such countries will find it necessary to use additional criteria in developing classifications that are more distinctive than a simple urban rural differentiation. Some of the additional criteria that may be useful are the percentage of the economically active population employed in agriculture, the general availability of electricity and/or piped water in living quarters and the ease of access to medical care, schools and recreation facilities. For certain countries where the facilities noted above are available in some areas that are still rural since agriculture is the predominant source of employment, it might be advisable to adopt different criteria in different parts of the country. Care must be taken, however, to ensure that the definition used does not become too complicated for application to the census and for comprehension by the users of the census results.
Even in the industrialized countries, it may be considered appropriate to distinguish between agricultural localities, market towns, industrial centres, service centres and so forth, within size-categories of localities.
Even where size is not used as a criterion, the locality is the most appropriate unit or classification for national purposes as well as for international comparability. If it is not possible to use the locality, the smallest administrative unit of the country should be used.
Some of the information required for classification may be provided by the census results themselves, while other information may be obtained from external sources. The use of information provided by the census (as, for example, the size-class of the locality or the percentage of the population employed in agriculture), whether alone or in conjunction with information from other sources, means that the classification will not be available until the relevant census results have been tabulated. If, however, the census plans call for the investigation of a smaller number of topics in rural areas than in urban areas or for a greater use of sampling in rural areas, the classification must be available before the enumeration takes place. In these cases, reliance must be placed on external sources of information, even if only to bring up to date any urban-rural classification that was prepared at an earlier date.
The usefulness of housing census data (for example, the availability of electricity and/or piped water) collected simultaneously with, or not too long before, the population census should be kept in mind. Images obtained by remote sensing may be of use in the demarcation or boundaries of urban areas when density of habitation is a criterion. For assembling information from more than one source, the importance of a well-developed system of geocoding should not be overlooked.
Locality is defined as a distinct population cluster
(also designated as inhabited place, population centre, settlement
etc.), in which the inhabitants live in neighbouring sets of living
In compiling vital statistics, the basis for geographic tabulation may be either place of occurrence, i.e., the locality, major civil division or other geographic place where the event occurred, or place of usual residence, i.e., the locality where the person in question (parent, decedent, marriage partner, etc.) usually resides.
The recommended classification of localities by size class is as follows:
This comprehensive classification would usually be too detailed for the tabulation of survey results. Only when surveys are based on very large sample sizes would they have sufficient numbers to permit such detailed classification. For survey results, therefore, consideration may be given to a much more condensed classification.
Urban/rural is a derived topic of high priority in a vital statistics system which is based on geographic information obtained from place of occurrence and place of usual residence. Because of national differences in the characteristics which distinguish urban from rural areas, the distinction between urban and rural population is not amenable to a single definition applicable to all countries. For this reason, each country should decide which areas are to be classified as urban and which as rural, in accordance with their own circumstances.
For national purposes as well as for international comparability, the most appropriate unit of classification is the size of locality or, if this is not possible, the smallest administrative division of the country. It must be recognized, however, that a distinction by urban and rural based solely on the size of the population of localities does not always offer a satisfactory basis for classification, especially in highly industrialized countries. Some countries have developed a classification of localities based not on population size alone but on “socioeconomic structure of the population”, in the localities.41 Others have tried to express degrees of urbanization by use of indices of population density etc. 103. The difficulty of applying these criteria to vital statistics lies in the fact that data on the relevant variables are seldom available.