SOFTWARE/STATA

 

Transforms and normality tests

Box–Cox transform

  • can be applied to the left-hand-side, right-hand-side, or both
  • parameters can be the same or different
  • maximum likelihood
  • zero-skewness log

Power transforms

  • search for power transform that converts variable into a normally distributed variable
  • graphical display of power-transformed variable
 

Tests of normality

  • Shapiro–Wilk
  • Shapiro–Francia
  • skewness and kurtosis test (D'Agostino with and without Royston correction)

© Copyright StataCorp LP 2005.


 
Copyright © 2005 TStat All rights reserved via Baden Powell, 8/I - 67039 - Sulmona (AQ) - Italia