Stats Assistance
One group vs a known value

One Sample t Test Calculator

Test whether your sample mean differs from a specific value, such as a national norm, a scale midpoint, or a benchmark score.

APA 7 write-up
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When to use a one sample t test

Use this test when you have one group and a meaningful comparison value. Examples: does average class performance differ from the national norm of 100? Does mean satisfaction differ from the scale midpoint of 3? Does average response time differ from a published benchmark?

Comparing two groups to each other instead? Use the independent samples t test or the paired samples t test.

Reading the result

The confidence interval reported here is for the difference between your sample mean and the test value. If it excludes zero, the test is significant at the corresponding alpha level. Cohen's d is the mean difference divided by the sample standard deviation.