However, due to some factors, it is unrealistic to investigate everyone.
The measure we take at this time is to investigate some people, such as 100 people.
Use the average wage of this 100 person as the estimate of the average wage of all people.
Since it is an estimate, it must have some deviation from the real average wage.
So the next step is to control this deviation with the help of probability theory in mathematics.
I can control or estimate this deviation, and it will not exceed much, such as 1%.
This method of estimating the whole data by extracting some data is statistics.
Of course, statistics contain more than that.
For example, use the data in a period of time to measure the income and sales profit of the enterprise and analyze the next development direction of the enterprise.
These are all statistics.