Democracy Definition & Meaning - Merriam-Webster

                                                                                                                              

                           Demography is a statistical measurement

Demography is a statistical measurement of population characteristics and dynamics. According to age and structure demography is not merely important in social life but social science and this entire particular student related to a human being they take and study these subject aspects as essential elementary and partial part to under reference of this logical we can agree, and demography study is almost part of social sciences.

Demography overlaps with many neighboring disciplines. Most demographers—at least in the United States—also identify themselves as sociologists, economists, anthropologists, geographers, historians, biologists, and so on. The demographic inquiry may be narrowly focused on demographic variables alone or broadly concerned with society, economy, and culture. The terms pure demography and formal demography are sometimes used to distinguish more narrowly focused interests in population composition and demographic dynamics, dealing entirely with demographic variables. An example of formal demographic analysis would be developing a theoretical model specifying the relationship between changes in infertility (treated as a cause) and changes in age composition (treated as an effect). A more extensive and less narrowly focused approach to demography is implied by the phrase population studies, which includes all of the above but also encompasses the study of relationships between demographic and non-demographic variables. The far-reaching implications of demographic variables in other disciplines have generated broad interest in such fields of study as social demography, economic demography, anthropological demography, bio-demography, and historical demography, to name a few. Two more preliminary remarks need to be made. Though you will undoubtedly find personal relevance to the topics throughout this textbook, one of the strengths of demography is that it allows us to see how the individual and his or her experiences fit into the larger demographic framework of the world. Demography takes these intensely personal experiences and considers them at the aggregate level of people, not the individual level. The very term―population refers to the number of people resident in some specified geographic area.

Likewise, demography describes characteristics of populations, not of individual members in those populations. Thus, the cartoon shown in Figure 1-1 is something of a demographer's inside joke. The second point is that demography is generally quantitative and statistical, although some demographers also use qualitative methods (see PetitandCharbit,2013; Kertzerand Fricke, 1997; Obermeyer,1997; Bogueetal.,1993, ch. 27). The aim of analysis in demographic work is to identify and measure precisely as possible the influences that underlie population changes. By so doing it is possible to deepen one's understanding of the variations observed in past experience, and also perhaps to arrive at a basis for the prediction of future trends. There must always, however, be some doubt about the chances that identified influences will continue to have an effect in the years to come. Even if a simple extra population of an existing trend is accepted as a valid assessment for the future, it should be possible, as the result of prior analysis, to attach some rough measure of confidence to the estimation.

The word 'trend 'is often misused. In the world of fashion, it frequently implies no more than whatever style happens to be current. More correctly, it refers to a change in time; thus, if the proportion of old people in a population had been 20 percent fifteen years ago, and 30 percent at this year's census, then clearly there had been, over this period, an aging trend. The trap into which many are liable to fall is to assume that this trend must continue. In fact, analysis is usually required in order to find out whether or not this is likely to happen. The main tasks of the demographer are, first, to understand the characteristics of his data; secondly, to observe and measure the past experience; thirdly, to study as far as possible the factors influencing the experience and causing the changes; and fourthly, to consider the prospects. In the third and technically most difficult stage, the analysis should be supplemented by an examination of any available information of a social, economic, or even psychological kind that could indicate, or illustrate, the background.

Great precision n is rarely justifiable in demography. Indeed, the observed statistics are subject to considerable variations, both in time and from one group or area to another. Whereas much of mathematical statistics is founded upon some assumption of homogeneity, in the study of the population this assumption is rarely justified; frequently, observed variations greatly exceed those to be expected by statistical theory, and the actual fluctuations where large numbers are involved can big, relatively, as their and on variations observed in small homogeneous groups. Consequently, the refinements of mathematical statistics are only of limited application in practical demography.