NAME

s.normal - tests for normality for sites.
(GRASS Sites Program)

SYNOPSIS

s.normal
s.normal help
s.normal [-q] input=name [tests=range[,range,...]]

DESCRIPTION

s.normal computes tests of normality on a site list.

OPTIONS

Flag:

-q
Quiet. Cut out the chatter when reading site list.

Parameters:

input=name
Name of sites list.
tests=range[,range,...]]
Tests of normality requested (see below).

NOTES

The tests that s.normal performs are indexed below. The tests that are performed are specified by giving an index, ranges of indices, or multiple thereof.
  1. Sample skewness and kurtosis
  2. Geary's a-statistic and an approximate normal transformation
  3. Extreme normal deviates
  4. D'Agostino's D-statistic
  5. Modified Kuiper V-statistic
  6. Modified Watson U^2-statistic
  7. Durbin's Exact Test (modified Kolmogorov)
  8. Modified Anderson-Darling statistic
  9. Modified Cramer-Von Mises W^2-statistic
  10. Kolmogorov-Smirnov D-statistic (modified for normality testing)
  11. Chi-Square test statistic (equal probability classes) and the number of degrees of freedom
  12. Shapiro-Wilk W Test
  13. Weisberg-Binghams W'' (similar to Shapiro-Francia's W')
  14. Royston's extension of W for large samples
  15. Kotz Separate-Families Test for Lognormality vs. Normality

EXAMPLE

s.normal input=soils tests=1-3,14
computes the sample skewness and kurtosis, Geary's a-statistic and an approximate normal transformation, extreme normal deviates, and Royston's W for the soils site list.

SEE ALSO

s.univar

AUTHOR

James Darrell McCauley, Agricultural Engineering, Purdue University