1, population: refers to the whole of the investigated object, also called matrix.

2. Individuals: Each member of a group is called an individual. For example, to investigate the service life of light bulbs produced by a factory, all the light bulbs produced by this factory are people, and each light bulb is an individual.

3. Sample: also known as "sub-sample", a part of individuals extracted from the population according to certain sampling rules. The number of individuals in a sample is called "sample size".

Second, the usage is different:

The population refers to the whole of the investigated object, the individual is the object of each investigation in the population, and the sample is a part of the individuals extracted from the population. Tips: First find out the objects to be investigated, so as to find out the people and individuals, and then find out the samples according to the data collected in this part.

Extended data

Case:

The whole is the whole of the research object in statistical analysis; Individual is every research object that constitutes the whole; The sample is all individuals extracted from the population X according to certain rules, and expressed by X 1, X2, Xn; The number of individuals in a sample is called the sample size, which is represented by n.

Just like studying the average height of a class, the height of all students in this class is the whole; The height of a classmate is 1 person; According to certain rules, the height of 20 students is studied, and the height of these 20 students is the sample; 20 is the sample size, which means n=20.