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Run an independent-samples (Student's or Welch's), paired or one-sample t-test from raw data or summary statistics. Get t, degrees of freedom, the p-value, a 95% confidence interval and Cohen's d.
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| Group 1 | M = 13.71, SD = 1.40, n = 10 |
|---|---|
| Group 2 | M = 11.35, SD = 1.03, n = 10 |
| t statistic | 4.300 |
| Degrees of freedom | 16.54 |
| p-value (two-sided) | < 0.001 |
| Mean difference | 2.360 (95% CI 1.199 to 3.521) |
| Cohen's d | 1.923 |
Independent samples, paired samples or one sample.
Paste raw values or type the means, SDs and sample sizes.
An APA-style sentence with t, df, p, CI and d.
Use an independent-samples t-test to compare the means of two separate groups, a paired t-test when the same people are measured twice, and a one-sample t-test to compare a mean with a known value.
Welch's t-test does not assume the two groups have equal variances and is a safe default for independent samples; Student's t-test assumes equal variances.
Welch's t-test is reliable whether or not the variances are equal, so it is a sensible default. Student's t-test is fine when the variances and sample sizes are similar.
It is the probability of a difference at least this large if there were truly no difference. Report it with the confidence interval and effect size.
Yes. Switch Data to Summary statistics and enter the means, standard deviations and sample sizes.