Weighted average is to multiply each value by the corresponding weight, and then add it to get the total value, and then divide it by the total number of units. The weighted average depends not only on the value (variable value) of each cell in the population, but also on the frequency (frequency) of each value.

Because the number of occurrences of each value plays a role in weighing its influence on the average, it is called weight. Weighted average is the average value of data with different specific gravity, which is to calculate the original data in a reasonable proportion.

In practical problems, when the weights are different, the average is calculated by weighted average, and when the weights are equal, the average is calculated by arithmetic average (arithmetic average is a special form of weighted average).

Extended data

Weighted average formula:

If x 1 appears f 1 times, x2 appears f2 times, …, and xk appears fk times among n numbers, it is called the weighted average of x 1, x2, …, xk. F 1, f2, …, fk are the weights of x 1, x2, …, xk.

Formula:? , among them. F 1, f2, …, fk are called weights.

Weighted average generally has two points to pay attention to:

1, and the overall average value is between the two parts;

2. The size of the overall average is related to the ratio of the absolute quantity of the two parts (cross method).

Baidu Encyclopedia-Average