Terms used in Population studies

• Birth Rate (or crude birth rate) is the number of live births per 1,000 of the population in a given year. (Not to be confused with the growth rate).
• Brain Drain is the emigration of a significant proportion of a country’s highly skilled, highly educated professional population, usually to other countries offering better economic and social opportunity (for example, physicians leaving a developing country to practice medicine in a developed country).
• Death Rate (or crude death rate) is the number of deaths per 1,000 of the population in a given year.
• Demographic Transition is the historical shift of birth and death rates from high to low levels in a population. The decline of mortality usually precedes the decline in fertility, thus resulting in rapid population growth during the transition period.
• Demography is the scientific study of human populations, including their sizes, compositions, distributions, densities, growth, and other characteristics, as well as the causes and consequences of changes in these factors.
• Dependency Ratio is the ratio of the economically dependent part of the population to the productive part; arbitrarily defined as the ratio of the elderly (ages 65 and older) plus the young (under age 15) to the population in the working ages (ages 15-64).
• Emigration is the process of leaving one country to take up permanent or semi-permanent residence in another.
• Emigration Rate is the number of emigrants departing an area of origin per 1,000 population in that area of origin in a given year.
• Growth Rate is the number of people added to (or subtracted from) a population in a year due to natural increase and net migration expressed as a percentage of the population at the beginning of the time period.
• Immigration is the process of entering one country from another to take up permanent or semi-permanent residence.
• Immigration Rate is the number of immigrants arriving at a destination per 1,000 population at that destination in a given year.
• Incidence Rate is the number of persons contracting a disease per 1,000 population at risk, for a given period of time.
• Infant Mortality Rate is the number of deaths of infants under age 1 per 1,000 live births in a given year.
• Life Expectancy is the average number of additional years a person could expect to live if current mortality trends were to continue for the rest of that person’s life. Most commonly cited as life expectancy at birth
• Migration is the movement of people across a specified boundary for the purpose of establishing a new or semi-permanent residence. Divided into international migration (migration between countries) and internal migration (migration within a country).
• Population is a group of objects or organisms of the same kind.
• Population Density Population per unit of land area; for example, people per square mile or people per square kilometer of arable land.
• Population Distribution is the patterns of settlement and dispersal of a population.
• Population change refers to change in the number of people during the specific time.
• Population growth is the increase in the number of individuals in a population.
• Population structure means the ‘make up’ or composition of a population. Looking at the population structure of a place shows how the population is divided up between males and females of different age groups.Population structure is usually shown using a population pyramid.
• Urbanization is growth in the proportion of a population living in urban areas.
• Refugee-is any person who is outside his or her country of nationality who is unable or unwilling to return to that country because of persecution or a well-founded fear of persecution.

To access more topics go to the O Level Geography Notes page