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On 5/8/2011 3:28 PM, Emad Mohamed wrote:
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<div><font class="Apple-style-span" size="4">My question is:
Do I need to use any significance test to show that
adding feature x really helps? if no, why not? and if yes,
what are the appropriate tests in such a case?</font></div>
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<br>
Significance tests are only relevant if you're testing a
representative sample of the data. If your sample is not
representative, no amount of significance testing will make it so.<br>
<pre class="moz-signature" cols="72">--
-Angus B. Grieve-Smith
Saint John's University
<a class="moz-txt-link-abbreviated" href="mailto:grvsmth@panix.com">grvsmth@panix.com</a>
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