Statistics - the science that studies the mass phenomena in the society in terms of quality and quantity.This is just one of the accepted definitions.There is a point of view on it, as a science that develops statistical methods for research conducted in different areas.
most significant and common features, properties and relation of phenomena and objects that exist objectively reflect certain concepts or categories.With their help, this science is exploring its own thing.One of these categories is a statistical aggregate.This large number of varying phenomena that exist in space and time.All of them are relatively uniform and have signs, bring them closer or different.
statistical population is characterized by the following properties:
- Indecomposability.When the appear or disappear some elements of statistical population, its qualitative basis with no breaks.For example, a characteristic community of students does not change the fact that every year in its ranks come freshmen and graduates them leave.
- Uniformity.Statistical population is always at least one thing in common for all of its elements.At the same time, this property is the same for them.This feature may have different values for different units.The extent to which statistical population is homogeneous, established during the investigation.And this property depends primarily on the objectives and the challenges that it is carried out.
- variation.This property is more important than the previous two.It manifests itself as follows: during the transition from one element to another statistical population is a change quantitative characteristic value.It can be the same for all components.In this case, to get an idea of what the statistical population, you can not study it fully, and consider only one constituent element.On the occurrence of variation affects a whole range of causes and conditions.Their finding, clarifying the economic discipline involved.But statistics only evaluates quantitatively how each cause affects the variation of a particular trait.This information is helping to make the right management decisions.
statistical population is divided into several groups:
- ones that create life.They have already formed a whole, regardless of whether or not were examined.This, for example, the aggregate of the industrial enterprises of the city, the totality of their employees.They exist in reality, they can be measured.
- groups that are formed specifically to carry out research.This, for example, readers of a certain set of statistical periodicals.
- hypothetical set.This set of stochastic (such as celestial bodies that exist in the galaxy).That is, they are only supposed to think.
Any statistical population belonging to any of the three groups has characteristic symptoms.You can classify them for many reasons.
For example, depending on the nature of expression signs are:
- descriptive (attribute).They are expressed in words (for example, education, ethnicity, gender).These features allow you to sum up how many units have one or another value.
- quantitative.They measure - numeric (eg, age, length of service, the amount of gain or loss, and others.).These features also allow you to summarize the number of those units that have a certain value, as well as the average or the sum of their value separately for aggregates.
