```Date: Aug 17, 2012 9:39 PM
Author: Richard Ulrich
Subject: Re: comparison between two value in a sample, please help...

On Fri, 17 Aug 2012 01:49:39 -0400, Rich Ulrich<rich.ulrich@comcast.net> wrote:[snip, a bunch]>>I *think*  what follows is a safe, conservative procedure -- >The minimum, proper fitted equation will show no less error>than the measurement error.  For that, the pooled SD isKeep in mind that the MS-residual is an estimate of the variance(which is the square of the standard deviation) of the residual.When I was learning to use regression, it helped me whenI realized that fact.  Then I started making a point of noticing thatvariance, and taking the square root ... just to make sure thatI was still analyzing the same set that I thought I was, and thatnothing was going strange.>about 42, or the "Mean-square-residual" is the square of>42, with 10 d.f.   Take the Mean square for Regression from>the 5-point regression and divide it by *this* residual, >instead of the computed residual, to get the safe F-test.Oops! slligh correction -- For the 5 point regression, each point is the average of three measures.  The SD of the *3*taken separately is 42; the SD of the average is, naturally,the raw SD divided by the square root of N, or sqrt(3).Or -  the MS is not 42-squared, but is 42-squared, divided by 3. >>The ratio of the two so-called Residual terms can be used as>a test of whether the regression is "over fitted".>Still useful, but you do use the corrected value.-- Rich Ulrich
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