Mood’s median non parametric hypothesis test compares the medians of two independent samples to determine if they are the same.
The Kruskal–Wallis Non-Parametric Hypothesis Test is used when a variable does not meet the normality assumptions of one-way ANOVA
Mann-Whitney Non Parametric Hypothesis Test is used to compare two sample means that come from the same population.
Ask ten people, “What is quality?” and you’ll get ten different answers. Look at industry definitions of ‘quality’ and how to measure it.
Rational sub grouping is the process of organizing the data into groups which were produced basically under the same conditions