1-Sample Wilcoxon
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Stat > Nonparametrics > 1-Sample Wilcoxon

You can perform a 1-sample Wilcoxon signed rank test of the median or calculate the corresponding point estimate and confidence interval. The Wilcoxon signed rank test hypotheses are

H0: median = hypothesized median versus H1: median ≠ hypothesized median

An assumption for the one-sample Wilcoxon test and confidence interval is that the data are a random sample from a continuous, symmetric population. When the population is normally distributed, this test is slightly less powerful (the confidence interval is wider, on the average) than the t-test. It may be considerably more powerful (the confidence interval is narrower, on the average) for other populations.

Dialog box items

Variables: Select the column(s) containing the variable(s) you want to test.

Confidence interval: Choose to calculate a one-sample Wilcoxon confidence interval for each column listed.

Level: Enter a confidence level between 0 and 100 (default is 95.0.)

Test median: Choose to perform a Wilcoxon signed-rank test, then specify the null hypothesis test value.

Alternative: Click the arrow to choose the kind of test performed by selecting less than (lower-tailed), not equal (two-tailed), or greater than (upper-tailed) from the drop-down box.