Statistical approaches in surface finishing. Part 2. non-parametric methods for data analysis

This paper is the second of a short series of articles aimed towards describing some of the various statistical methods and approaches that have been used in surface finishing. The methods fall broadly into two areas: analysis and design-of-experiments. In the first paper, the subject was briefly introduced followed by a discussion of parametric statistics hypothesis testing. This second paper logically continues with descriptions of the various non-parametric tests and situations where these could be applied, all within the context of surface finishing applications.