Bartlett's Test Calculator

The Bartlett's test calculator determines the test statistic and corresponding p-value based on the variances of multiple groups.

Result:

How to Use the Bartlett's Test Calculator?

  1. Enter the data values for up to five groups. The input format should be 4,6,8,10 or 4 6 8 10.
  2. Select the significance level.
  3. Press the 'Calculate' button to run the Bartlett's test.
  4. Finally, the tool returns the test statistic (T) and P-value corresponding to the test.
  5. In addition, it also shows whether the P-value result is significant or not.

What is Bartlett's Test?

Bartlett's test is used to check if multiple groups (samples) have equal variances, which verifies the assumption in parametric statistical tests like One-Way ANOVA.

If the p-value is less than 0.05, it suggests that the variances are unequal across the groups.

How to Calculate?

The following formula is used to compute the test statistic (T) for Bartlett's Test:

T =  
(N - k)
C
 × ln(sp2) - Σ (ni - 1) ln(si2)
C = 1 + 
1
3(k - 1)
( Σ
1
ni - 1
 - 
1
N - k
)
sp2 =  
Σ(ni - 1) × si2
N - k

Where,
k = Number of groups (samples),
N = Total number of data points,
C = Correction factor,
sp2 = Pooled variance,
si2 = Sample variance of the ith group,
ni = Sample size of the ith group.