Every element that constitutes a group is called an individual, and in a group composed of multiple enterprises, each enterprise is an individual; In a group composed of multiple families, each family is an individual; In a group of many people, everyone is an individual.
Sample size refers to the number of units contained in a sample, which is generally expressed by n, which is a very important concept in sampling inference. The size of sample size is directly related to the accuracy of inference estimation, that is, under a given overall situation, the larger the sample size, the smaller the representative error of statistical estimator, and conversely, the smaller the sample size, the greater the estimation error.
Extended data
Population classification
1, according to the number of containing units, can be divided into finite population and infinite population.
A population contains a limited number of units, which is called a finite population, such as population, enterprises, shops, etc. The number of units contained in a population is infinite, which is called infinite population, such as the output of a certain product produced continuously and the quantity of fish resources in the ocean. The time series population is also an infinite population.
A limited number of people can make a comprehensive investigation or not. However, in the infinite population, only a part of units can be selected for incomplete investigation, so as to infer the population.
2. According to the attributes of company logo, it can be divided into variable crowd and attribute crowd.
The population that reflects the composition of quality mark units is called attribute population; The group that reflects the composition of quantitative signs is called variable group.
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