man v.normal () - tests for normality for points.

NAME

v.normal - tests for normality for points.

SYNOPSIS

v.normal

v.normal help

v.normal [-rql] map=string tests=range[,range,...] column=string

Flags:

"-r
Use only points in current region
"-q
Quiet
"-l
lognormal

Parameters:

"map=string
point vector defining sample points
"tests=range[,range,...]
Lists of tests (1-15): e.g. 1,3-8,13
"column=string
Attribute column

DESCRIPTION

v.normal computes tests of normality on vector points.

NOTES

The tests that v.normal performs are indexed below. The tests that are performed are specified by giving an index, ranges of indices, or multiple thereof.

Sample skewness and kurtosis
Geary's a-statistic and an approximate normal transformation
Extreme normal deviates
D'Agostino's D-statistic
Modified Kuiper V-statistic
Modified Watson U^2-statistic
Durbin's Exact Test (modified Kolmogorov)
Modified Anderson-Darling statistic
Modified Cramer-Von Mises W^2-statistic
Kolmogorov-Smirnov D-statistic (modified for normality testing)
Chi-Square test statistic (equal probability classes) and the number of degrees of freedom
Shapiro-Wilk W Test
Weisberg-Binghams W'' (similar to Shapiro-Francia's W')
Royston's extension of W for large samples
Kotz Separate-Families Test for Lognormality vs. Normality

EXAMPLE

v.normal map=soils tests=1-3,14 col=flt1

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 vector points.

SEE ALSO

v.univar

AUTHOR

James Darrell McCauley ,



when he was at: Agricultural Engineering Purdue University

Last changed: $Date: 2004/10/16 10:30:43 $

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