Time series

From Demopædia
Jump to: navigation, search
Time series  (TIME series)

When the movement of a demographic variable in time is considered, a demographic time series 1 is obtained. It is sometimes possible to decompose a time series into a trend 2 around which there are fluctuations 3, variations 3 (141-1) or deviations 3 (141-2). Where such fluctuations tend to recur after certain periods, they are called periodic fluctuations 4 or sometimes cyclical fluctuations 4, In demography the most common period is a year, and the fluctuations in sub-periods are called seasonal fluctuations 5. The fluctuations that remain after trend and periodic fluctuations have been eliminated are called irregular fluctuations 6. They may be due to exceptional factors, e. g. to mobilization, or sometimes they are chance fluctuations 7 or random fluctuations 7.

United nations
Departement of Economic and Social Affairs
Population Division

United Nations Logo

International Union
for the Scientific Study
of Population

IUSSP logo
Personal tools
In other languages