
257Data Analysis and Statistical Testing
6.4.13 Friedman Test
Friedman test is a nonparametric test, which can be used to rank a set of k treatments over
multiple data instances or subjects (Friedman 1940). The test can be used to investigate
the existence of any statistical difference between various treatments. It is generally used
in a scenario where same set of treatments (techniques/methods) are repeatedly applied
over n independent data instances or subjects. A uniform measure is required to com-
pute the performance of different treatments on n data instances. However, Friedman
test does not require that the samples should be drawn from ...