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Paired t-TestStatLens

Choose a dataset:

Paste paired data (CSV with two numeric columns):

Open a CSV, TSV, or JSON file:

Mean difference (d̄): SD of differences (sₓ): Number of pairs (n):

Results update as you type — no need to press anything.

Variable 1 (group 1): Variable 2 (group 2):

Parameters

H₀: μ_d = 0 =

H_a: μ_d 0 0

Confidence level

Select a dataset or enter summary statistics — results appear automatically.

Just estimating? Confidence Interval for a Mean Difference →

Paired t-Test

Test whether the mean of the paired differences μ_d differs from a hypothesized value, using a t-statistic and the t-distribution. Each row is one pair (for example, a before and an after measurement on the same subject).

Load data from the Datasets, Edit Data (two columns, such as before and after), or Open File/URL tab, or use Enter Summary to type the mean difference, its SD, and n.
Variable selectors let you pick the two paired columns when the data has more than two.
Alternative (H_a): click the toggle to cycle ≠, <, > for a two-sided or one-sided test.
Null value: standard mode tests μ_d = 0. Turn on Expert mode (settings gear) to make the null difference δ₀ editable.
Conditions checkpoint reminds you to check the number of pairs and the shape of the differences.
Confidence level sets the matching interval (default 0.95).
Results — t, df, p-value, the confidence interval, and the plot — appear automatically as you change inputs. There is no Compute button.

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