The units of variance are the square of the units of the original data.
Let's break this down further:
Variance is calculated by taking the average of the squared differences between each data point and the mean. Since you are squaring the differences, the resulting values are in square units. For example, if your original data is in terms of length (e.g., meters), then the variance will be in terms of square length (e.g., square meters).
To make this clearer, consider an example: Suppose you are measuring the heights of individuals in a population, and the heights are given in meters. The units of the variance in this case will be square meters (m^2), because you are squaring the differences in height (meters) to calculate the variance.
This is why variance is often used in conjunction with the standard deviation, which is the square root of the variance. The standard deviation has the same unit as the original data, making it more interpretable in terms of the original measurement units.
