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<h2>DESCRIPTION</h2>
<em>v.normal</em> computes tests of normality on vector points.
<h2>NOTES</h2>
The tests that <em>v.normal</em> performs are indexed
below. The tests that are performed are specified by
giving an index, ranges of indices, or multiple thereof.
<ol>
<li> Sample skewness and kurtosis</li>
<li> Geary's a-statistic and an approximate normal transformation</li>
<li> Extreme normal deviates</li>
<li> D'Agostino's D-statistic</li>
<li> Modified Kuiper V-statistic</li>
<li> Modified Watson U^2-statistic</li>
<li> Durbin's Exact Test (modified Kolmogorov)</li>
<li> Modified Anderson-Darling statistic</li>
<li> Modified Cramer-Von Mises W^2-statistic</li>
<li> Kolmogorov-Smirnov D-statistic (modified for normality testing)</li>
<li> Chi-Square test statistic (equal probability classes) and
the number of degrees of freedom</li>
<li> Shapiro-Wilk W Test</li>
<li> Weisberg-Binghams W'' (similar to Shapiro-Francia's W')</li>
<li> Royston's extension of W for large samples</li>
<li> Kotz Separate-Families Test for Lognormality vs. Normality</li>
</ol>
<h2>EXAMPLE</h2>
<!-- do a meaningful example -->
Compute the sample skewness and kurtosis, Geary's
a-statistic and an approximate normal transformation,
extreme normal deviates, and Royston's W for the
<em>random</em> vector points:
<div class="code"><pre>
g.region raster=elevation -p
v.random random n=200
v.db.addtable random column="elev double precision"
v.what.rast random rast=elevation column=elev
v.normal random tests=1-3,14 column=elev
</pre></div>
<!-- TODO: find references , e.g.
http://www.itl.nist.gov/div898/handbook/eda/section3/eda35.htm
-->
<h2>SEE ALSO</h2>
<em>
<a href="v.univar.html">v.univar</a>
</em>
<h2>AUTHORS</h2>
<a href="http://mccauley-usa.com/">James Darrell McCauley</a>
<a href="mailto:darrell@mccauley-usa.com"><darrell@mccauley-usa.com></a>,
<br>when he was at:
<a href="https://engineering.purdue.edu/ABE/">Agricultural Engineering</a>
<a href="http://www.purdue.edu/">Purdue University</a>
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