Semakan pada 05:37, 25 Februari 2013

101

Demografi¹ adalah kajian saintifik mengenai penduduk berkaitan saiz, struktur² dan pembangunan; ia mengambilkira aspek kuantitatif bagi ciri-ciri umumnya. Ia adalah asas kepada Templat:NewTextTerm yang meliputi pelbagai bidang yag saling berkaitan seperti demografi ekonomi (104-1), demografi sosial (104-2), genetik kependudukan (104-4), demografi sejarah (102-1), demografi matematik (102-6) dan begitu juga sumbangan daripada perundangan, perubatan, epidemiologi (423-6), sosiologi, psikologi, geografi dan falsafah. Dalam terminologi statistik, sebarang pengumpulan bagi elemen-elemen yang berbeza dipanggil populasi³, yang sama adalah sinonim dengan sejagat³. Walau bagaimanapun, dalam pengunaan demografi, istilah populasi⁴ merujuk kepada kesemua penghuni⁵ bagi kawasan tertentu, meskipun kadangkala ia digunakan oleh sebahagian penghuni sahaja[sebagai contoh, penduduk umur persekolahan (cf. 346-7), penduduk boleh berkahwin (cf. 514-2)]. Kumpulan-kumpulan tersebut dipanggil sub-populasi⁶. Istilah kependudukan kebiasaannya digunakan untuk menunjukkan lebih spesifik saiz⁷, sebagai contoh, jumlah bilangan⁷ bagi agregat yang disebut dalam no. 101-4.

102

Certain sub-disciplines within demography have received special names reflecting their objectives or their methodology. Historical demography¹ deals with populations of the past for which written records are available. In the absence of such sources, the study of ancient populations takes the name of paleo-demography² . In descriptive demography³ the numbers, geographical distribution, structure and change of human populations are described by means of population statistics⁴ or demographic statistics⁴ . The treatment of quantitative relations among demographic phenomena in abstraction from their association with other phenomena, is called theoretical demography⁵ or pure demography⁵ ; because of its resort to various mathematical methods, in practice it is identified with mathematical demography⁶. A piece of research that applies the tools of demographic analysis (103-1) to an actual population is often called a demographic study⁷. This study can focus on the Templat:NewTextTerm or Templat:NewTextTerm, ie the population change and its indicators during a short and recent period. All the preceding disciplines place a great emphasis on the numerical aspects of the phenomena, and are sometimes referred to as formal demography⁹, when they apply only to the size and structure of the population. In contrast the broader term population studies¹⁰ also includes the treatment of relations between demographic events and social, economic or other phenomena.

103

Demographic analysis¹ is that branch of formal demography which controls for the effect of population size and structure on demographic phenomena² by isolating the effects of each demographic variable from the others, the latter of which are called Templat:NewTextTerm. It also studies the relations between demographic variables and how they interact to form population structures. A distinction is made between cohort analysis⁴ or generational analysis⁴ which focuses on a well defined cohort (cf. 117-2) followed through time, and cross-sectional analysis⁵ or period analysis⁵ which focuses on the demographic phenomena that occur during a precise time interval (such as a calendar year) among several cohorts.

104

The study of relations between demographic phenomena on one hand and economic and social phenomena on the other forms another branch of the subject. The terms economic demography¹ and social demography² have been used by some writers. Demography also deals with the study of population quality³. This phrase may be used with reference to all sorts of social and personal characteristics. In a slightly different sense the term primarily refers to the distribution and transmission of hereditary characteristics (910-3) which are the subject of population genetics⁴ . Human ecology⁵ is the study of the distribution and organization of communities with attention to the operation of competitive and cooperative processes and has part of its subject matter in common with demography. Fields of research and methodology are even more intertwined in the case of demography and Templat:NewTextTerm. It is also the case for biometry⁶ or biometrics⁶ and Templat:NewTextTerm which deal with the application of statistical methods to all forms of biological and medical research.

105

Finally, there is the study of population theories¹. This term should not be confused with theoretical demography (102-5). Population theories are designed to explain or predict the interaction between changes in population and economic, social, psychological or other factors; they include purely conceptual treatments. Population theories occasionally form the basis of population policy² (cf. §930), which deals with measures designed to influence population changes.

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