This dialog is activated by selecting the **Mood's Median Test...** command from the Statistics -> Nonparametric Tests -> menu. It can be used in order to test whether several samples originate from the same distribution.

QtiPlot combines the scores from the k input samples in the *Selected Data* box.
These N values (*N = n _{1} + n_{2} +...+ n_{k}*,
where

This test uses the *Chi-Square* statistic (χ^{2}) which is calculated using the following formula:
χ^{2} = ΣΣ(N_{ij}-E_{ij})^{2}/E_{ij},
where *E _{ij} = R_{i}n_{j}/N*,

QtiPlot computes an approximated p-value, which is the probability of a chi-squared value of at least *χ ^{2}* being observed:

The data sets selected in the *Available data* window can be added to the analysis either by pressing the left to right arrow button or by dragging and dropping them onto the right side window.