Mann-Whitney U检验计算器
执行Mann-Whitney U检验，比较两个独立样本的分布差异，作为独立样本t检验的非参数替代方法。
U Statistic
90.0
U2 Statistic30.0
Z Approximation1.9781
U Statistic vs Sample 1 Size
公式
Mann-Whitney U Test
U = n1*n2 + n1*(n1+1)/2 - R1
Compares two independent groups without assuming normality.
计算示例
n1=10, n2=12, R1=85.
- 01U1 = 120 + 55 - 85 = 90
- 02U2 = 120 - 90 = 30
常见问题
When use Mann-Whitney vs t-test?
When data are ordinal or not normally distributed.
How to calculate ranks?
Combine samples, sort, assign ranks. Average ties.
What does significant U mean?
The two groups differ in central tendency.
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