If you enter raw data, the tool will run the Shapiro-Wilk normality test and calculate outliers, as part of the paired-t test calculation.

**Header**: You may change groups' name to the real names.**Data**: When entering data, press Enter after each value.

The number of observations must be identical in both groups. (Difference = right - left)

You may copy data from Excel, Google sheets or any tool that separate data with **Tab** and **Line Feed**.

Copy the data,**one block of 3 consecutive columns includes the header**, and paste below.

Copy the data,

Copy the data,

It is okay to leave empty cells, empty cells or non numeric cells won't be counted

validation message

Hypotheses

H_{0}: μ_{d} ≥ = ≤ μ_{0}

H_{1}: μ_{d} < ≠ > μ_{0}

Test statistic

T-student distribution

Two-tailed test example:

Treatment is given to 50 people to reduce the cholesterol level. The expected reduction is 10mg/dL. The researcher takes two measures for each person before and after the treatment. The average reduction of the cholesterol level is 12mg/dL. (x

Both results are interesting, if the reduction is larger than the expected or if it is lower.

Right-tailed example.

Does the treatment for pattern hair loss effective?

Measurment: hair density, hairs per square cm.

Check the

H

H