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Calcimator

Kruskal-Wallis Test Calculator

Perform a Kruskal-Wallis H test to compare rank distributions across multiple independent groups.

Inputs

Results

H Statistic

2.52

P-Value (approx)

0.28

Degrees of Freedom2
Significant at α=0.05 (1=Yes)0
Effect Size (η²H)0.02
How to Use This Calculator
  1. Enter Total Observations (N), Number of Groups (k), and Group 1 Size (n₁).
  2. Set Group 1 Rank Sum (R₁), Group 2 Size (n₂), and Group 2 Rank Sum (R₂).
  3. Adjust Group 3 Size (n₃), Group 3 Rank Sum (R₃) as needed.
  4. Review H Statistic and P-Value (approx).
  5. Use Degrees of Freedom and Significant at α=0.05 (1=Yes) to inform your decision.

How the result changes with Total Observations (N)

Total Observations (N)H StatisticP-Value (approx)
10,003-30,0121
35,002-105,0091
65,001-195,0061
90,000-270,0031

What each input means

Total Observations (N)
Total number of observations across all groups combined.
Number of Groups (k)
Number of independent groups being compared (2-5).
Group 1 Size (n₁)
Number of observations in the first group.
Group 1 Rank Sum (R₁)
Sum of ranks for Group 1 after ranking all observations together.
Group 2 Size (n₂)
Number of observations in the second group.
Group 2 Rank Sum (R₂)
Sum of ranks for Group 2 after ranking all observations together.
Group 3 Size (n₃)
Number of observations in the third group.
Group 3 Rank Sum (R₃)
Sum of ranks for Group 3 after ranking all observations together.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Total Observations (N) = 30, Number of Groups (k) = 3, Group 1 Size (n₁) = 10, Group 1 Rank Sum (R₁) = 120 = 8 input(s) provided
  2. Calculate H Statistic
    H Statistic
    2.5161 = 2.5161
  3. Calculate P-Value
    P-Value
    0.2837 = 0.2837
  4. Calculate Degrees of Freedom
    Degrees of Freedom = df
    2 = 2
  5. Calculate Significant at α=0.05
    Significant at α=0.05
    0 = 0

Engine last updated . Checked against 1 independently-derived test — how we verify calculators.

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