05-06-2018 07:37 AM
I'd like to ask about the output on my shapiro wilk and anova test,
in the output table written that P Value is Pr <W, what is the meaning of the expression?why use less than sign?
As well as on ANOVA written that Pr> F, what does that mean? why use more than sign?
05-06-2018 05:52 PM
This provides a decision boundary to decide whether a variable is normally distributed or not using shapiro wilk based on probability of observing shapiro statistic under the null hypothesis. Same is true for ANOVA which is used to compare means of a continuous variable across different levels of a classification variable.
05-07-2018 07:40 PM
Think of Pr <W as probability of a smaller W statistic
Pr>F as probability of a larger F statistic
Direction will be based on the actual type of test statistic and its distribution and the value(s) of related elements such as degrees of freedom and possibly hypothesis test options (one-tailed vs. two-tailed for instance)