偏度计算器
计算数据分布的偏度，判断数据的对称性。
Pearson Skewness Coefficient
1.5000
Mean - Median Difference5.0000
Pearson Skewness Coefficient vs Mean
公式
How to Estimate Skewness
Pearson's Second Coefficient of Skewness
Skewness = 3 * (Mean - Median) / Standard Deviation
This is an approximation. The exact moment-based skewness requires raw data.
计算示例
A dataset has mean 55, median 50, and SD 10. Estimate the skewness.
- 01Skewness = 3 * (55 - 50) / 10
- 02= 3 * 5 / 10
- 03= 15 / 10 = 1.5
- 04Positive value indicates right skew
常见问题
What does positive skewness mean?
The distribution has a longer right tail. Most values cluster to the left, with some high outliers pulling the mean above the median. Income distributions are typically positively skewed.
What skewness value is considered significant?
A rough guideline: |skewness| < 0.5 is approximately symmetric, 0.5-1 is moderately skewed, and > 1 is highly skewed.
Why use Pearson's approximation?
It requires only three summary statistics (mean, median, SD) rather than the entire raw dataset. It works well for unimodal, moderately skewed distributions.
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