A population is a summation of all the organisms of the same group or species, which live in the same geographical area, and have the capability of interbreeding. Also given in percent is each country's population compared to the population of the world. According to a separate estimate by the United Nations, world population exceeded 7 billion in October 2011.
Predicted growth and decline
Population growth increased significantly as the Industrial Revolution gathered pace from 1700 onwards. The last 50 years have seen a yet more rapid increase in the rate of population growth due to medical advances and substantial increases in agricultural productivity, particularly beginning in the 1960s, made by the Green Revolution. In 2007 the United Nations Population Division projected that the world's population will likely surpass 10 billion in 2055. Its predicted by experts that the population will decline before the year 2100.
Replacement fertility is the total fertility rate at which newborn girls would have an average of exactly one daughter over their lifetimes. That is, women have just enough female babies to replace themselves.
If there were no mortality in the female population until the end of the childbearing years then the replacement level of TFR would be very close to 2.0 (actually slightly higher because of the excess of boy over girl births in human populations).
However, the replacement level is also affected by mortality, especially childhood mortality.
The replacement fertility rate is roughly 2.1 births per woman for most industrialized countries, but ranges from 2.5 to 3.3 in developing countries because of higher mortality rates.
What Is a Statistical Population?
There are several terms that are fundamental to the study of statistics. One such term, which is always in the background of any statistics problem, is a population. It is crucial to understand who or what comprises a statistical...