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	<title>Comments on: Choosing a Trendline Type</title>
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		<title>By: Jon Peltier</title>
		<link>http://peltiertech.com/WordPress/choosing-a-trendline-type/comment-page-1/#comment-3777</link>
		<dc:creator>Jon Peltier</dc:creator>
		<pubDate>Tue, 09 Sep 2008 16:39:01 +0000</pubDate>
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		<description>Michael -

&quot;Lots of things in nature are squared relationships.&quot;

Very true. One major problem with polynomial fits is that using them effectively separates the data from any resemblance to a physical model. I touched on this in &lt;a title=&quot;Graphical Approach to a Simple Physics Problem&quot; href=&quot;http://peltiertech.com/WordPress/2008/09/08/graphical-approach-to-a-simple-physics-problem/&quot; rel=&quot;nofollow&quot;&gt;Graphical Approach to a Simple Physics Problem&lt;/a&gt;, pointing out that the relationship to hole diameter squared was probably a linear first order relationship to hole area.

In follow-up discussions I will assume powers of 2 and 0.5 and show how to optimize the pre-exponential coefficient.</description>
		<content:encoded><![CDATA[<p>Michael -</p>
<p>&#8220;Lots of things in nature are squared relationships.&#8221;</p>
<p>Very true. One major problem with polynomial fits is that using them effectively separates the data from any resemblance to a physical model. I touched on this in <a title="Graphical Approach to a Simple Physics Problem" href="http://peltiertech.com/WordPress/2008/09/08/graphical-approach-to-a-simple-physics-problem/" rel="nofollow">Graphical Approach to a Simple Physics Problem</a>, pointing out that the relationship to hole diameter squared was probably a linear first order relationship to hole area.</p>
<p>In follow-up discussions I will assume powers of 2 and 0.5 and show how to optimize the pre-exponential coefficient.</p>
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		<title>By: Michael</title>
		<link>http://peltiertech.com/WordPress/choosing-a-trendline-type/comment-page-1/#comment-3774</link>
		<dc:creator>Michael</dc:creator>
		<pubDate>Tue, 09 Sep 2008 16:24:38 +0000</pubDate>
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		<description>Hi Jon -

Looking at the results, I want to jump to

y = 13.508x^.5  and y = 161.77x^-2

Lots of things in nature are squared relationships.

...mrt</description>
		<content:encoded><![CDATA[<p>Hi Jon -</p>
<p>Looking at the results, I want to jump to</p>
<p>y = 13.508x^.5  and y = 161.77x^-2</p>
<p>Lots of things in nature are squared relationships.</p>
<p>&#8230;mrt</p>
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