When the value of the positive skewness coefficient is positive, it means that the data is positive skewness or right skewness. When the value of negative skewness coefficient is negative, it means that the data is negative skewness or left skewness.

When the data is symmetrically distributed about the mean, the skewness is 0; The more dispersed the data on the right, the more biased it is to the right, and vice versa. If the mode is less than the median, the left side is more concentrated and the right side is more dispersed, then it is right deviation.

Left bias refers to the mode > average > median of data.

Right bias refers to the mode of data.