You use non-parametric hypothesis tests when you don’t know, can’t assume, and can’t identify what kind of distribution your have.
A Six Sigma Black Belt allocates 100% effort to a project, and they often train green belts while managing Six Sigma projects.
Six Sigma Master Black Belts are 100% allocated. Six Sigma Master Black Belts often mentor aspiring black belts. Learn more in this overview.
A Six Sigma Black Belt is usually the Six Sigma Project Manager, and to succeed they must follow strong project management techniques.
A Green Belt knows a fair amount about Six Sigma methodology, and can support a Black Belt in a major project or take on minor projects.