<div dir="ltr"><div class="gmail_default" style="font-size:small">Hi Leo,</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">I just checked the stddev documentation, and didn't see the same mention of "population" that you did.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">The first line of this page states:</div><div class="gmail_default" style="font-size:small"><i><br> "Calculates the sample standard deviation."</i><br></div><div class="gmail_default" style="font-size:small"><i><br></i></div><div class="gmail_default" style="font-size:small">It does mention population later in this documentation, and I need to look into why this is. I think this is an error in the documentation.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">As for the "stdMonTLL" function, it uses dim_stddev under the hood, so this should also be sample standard deviation.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">--Mar</div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Jan 28, 2015 at 3:00 AM, Kampenhout, L. van (Leo) <span dir="ltr"><<a href="mailto:L.vanKampenhout@uu.nl" target="_blank">L.vanKampenhout@uu.nl</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
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</font>I just stumbled upon the following inconsistency. In the description of function stddev it is written that (<a href="http://www.ncl.ucar.edu/Document/Functions/Built-in/stddev.shtml" target="_blank">http://www.ncl.ucar.edu/Document/Functions/Built-in/stddev.shtml</a>)<br>
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</font><i> (…) this function calculates the population standard deviation.</i><br>
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</font>However, I’m afraid it does not compute the <b>population</b> std but rather the
<b>sample</b> std. Example program attached.<br>
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</font>I see two solutions: <br>
(1) either change the documentation, such that is states specifically this function computes the sample standard deviation (perhaps also add an explanation why this is better).<br>
(2) change the code . This will create a backward incompatibility and many user scripts may yield different results. </div>
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<div>As a side note, function stdMonTLL also computes the sample std, second example program attached. <font color="#0f61c8"><br>
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</font>Kind regards,<br>
Leo<br>
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</font>____________________________________________________________<br>
<font color="#0f61c8"><br>
</font>Leo van Kampenhout<br>
Institute for Marine and Atmospheric Research (IMAU), Utrecht University<br>
BBG room 672<br>
Princetonplein 5, 3584 CC Utrecht, The Netherlands<span> </span><br>
<a href="tel:%2B31%2030%202533271" value="+31302533271" target="_blank">+31 30 2533271</a><br>
<a href="mailto:L.vanKampenhout@uu.nl" target="_blank">L.vanKampenhout@uu.nl</a><br>
<a href="http://www.uu.nl/wce" target="_blank">www.uu.nl/wce</a><br>
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