Two-Sample T-Test Calculator
From Summary Statistics
Enter means, standard deviations, and sample sizes
From Raw Data (3 values each)
Enter individual values for each group
Formula
t = (mean1 - mean2) / sqrt(s1^2/n1 + s2^2/n2)
Frequently Asked Questions
What is a two-sample t-test?
A two-sample t-test compares the means of two independent groups to determine if they are statistically significantly different from each other.
What is the difference between pooled and Welch t-test?
The pooled t-test assumes equal variances. The Welch t-test does not assume equal variances and adjusts the degrees of freedom accordingly. Welch is generally more robust.
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