<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Mon, Jan 26, 2015 at 10:31 AM, Antoine Pitrou <span dir="ltr"><<a href="mailto:solipsis@pitrou.net" target="_blank">solipsis@pitrou.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">> But throughout all this -- I haven't thought of a single case where I would<br>
> prefer a symmetric test and it would matter.<br>
<br>
</span>But then it begs the question: are there cases where an asymmetric test<br>
matters?</blockquote><div><br></div><div>Yes -- see the example in the PEP and on this list. If you have a known value, and you want to know whether the value at hand is within some error of the known value, then you want an asymmetric test -- and if you have errors on order of 10% -- it does make a difference. Granted, I don't expect this use case to be common, but it was brought up on this list.</div><div> <br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Simplicity has its virtues.</blockquote><div><br></div><div>But which is more simple? I came to the conclusion that the asymmetric was simpler to explain and reason about in any case. </div></div><br clear="all"><div>-Chris</div><div><br></div><div><br></div>-- <br><div class="gmail_signature"><br>Christopher Barker, Ph.D.<br>Oceanographer<br><br>Emergency Response Division<br>NOAA/NOS/OR&R (206) 526-6959 voice<br>7600 Sand Point Way NE (206) 526-6329 fax<br>Seattle, WA 98115 (206) 526-6317 main reception<br><br><a href="mailto:Chris.Barker@noaa.gov" target="_blank">Chris.Barker@noaa.gov</a></div>
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