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diff --git a/docs/loq.html b/docs/loq.html deleted file mode 100644 index 352737f..0000000 --- a/docs/loq.html +++ /dev/null @@ -1,191 +0,0 @@ -<!DOCTYPE html> -<html lang="en"> - <head> - <meta charset="utf-8"> -<title>loq. chemCal 0.1-37</title> -<meta name="viewport" content="width=device-width, initial-scale=1.0"> -<meta name="author" content=""> - -<link href="css/bootstrap.css" rel="stylesheet"> -<link href="css/bootstrap-responsive.css" rel="stylesheet"> -<link href="css/highlight.css" rel="stylesheet"> -<link href="css/staticdocs.css" rel="stylesheet"> - -<!--[if lt IE 9]> - <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script> -<![endif]--> - -<script type="text/x-mathjax-config"> - MathJax.Hub.Config({ - tex2jax: { - inlineMath: [ ['$','$'], ["\\(","\\)"] ], - processEscapes: true - } - }); -</script> -<script type="text/javascript" - src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"> -</script> - </head> - - <body> - <div class="navbar"> - <div class="navbar-inner"> - <div class="container"> - <a class="brand" href="index.html">chemCal 0.1-37</a> - <div class="nav"> - <ul class="nav"> - <li><a href="index.html">Home</a></li> - <li><a href="reference.html">Reference</a></li> - </ul> - </div> - </div> - </div> -</div> - - - <div class="container"> - <header> - - </header> - - <h1>Estimate a limit of quantification (LOQ)</h1> - -<div class="row"> - <div class="span8"> - <h2>Usage</h2> - <pre><span class="functioncall"><a href='loq.html'>loq</a></span><span class="keyword">(</span><span class="symbol">object</span><span class="keyword">,</span> <span class="symbol">...</span><span class="keyword">,</span> <span class="argument">alpha</span> <span class="argument">=</span> <span class="number">0.05</span><span class="keyword">,</span> <span class="argument">k</span> <span class="argument">=</span> <span class="number">3</span><span class="keyword">,</span> <span class="argument">n</span> <span class="argument">=</span> <span class="number">1</span><span class="keyword">,</span> <span class="argument">w.loq</span> <span class="argument">=</span> <span class="string">"auto"</span><span class="keyword">,</span> - <span class="argument">var.loq</span> <span class="argument">=</span> <span class="string">"auto"</span><span class="keyword">,</span> <span class="argument">tol</span> <span class="argument">=</span> <span class="string">"default"</span><span class="keyword">)</span></pre> - - <h2>Arguments</h2> - <dl> - <dt>object</dt> - <dd> - A univariate model object of class <code><a href='http://www.rdocumentation.org/packages/stats/topics/lm'>lm</a></code> or - <code><a href='http://www.rdocumentation.org/packages/MASS/topics/rlm'>rlm</a></code> - with model formula <code>y ~ x</code> or <code>y ~ x - 1</code>, - optionally from a weighted regression. If weights are specified - in the model, either <code>w.loq</code> or <code>var.loq</code> have to - be specified. - </dd> - <dt>alpha</dt> - <dd> - The error tolerance for the prediction of x values in the calculation. - </dd> - <dt>...</dt> - <dd> - Placeholder for further arguments that might be needed by - future implementations. - </dd> - <dt>k</dt> - <dd> - The inverse of the maximum relative error tolerated at the - desired LOQ. - </dd> - <dt>n</dt> - <dd> - The number of replicate measurements for which the LOQ should be - specified. - </dd> - <dt>w.loq</dt> - <dd> - The weight that should be attributed to the LOQ. Defaults - to one for unweighted regression, and to the mean of the weights - for weighted regression. See <code><a href='massart97ex3.html'>massart97ex3</a></code> for - an example how to take advantage of knowledge about the - variance function. - </dd> - <dt>var.loq</dt> - <dd> - The approximate variance at the LOQ. The default value is - calculated from the model. - </dd> - <dt>tol</dt> - <dd> - The default tolerance for the LOQ on the x scale is the value of the - smallest non-zero standard divided by 1000. Can be set to a - numeric value to override this. - </dd> - </dl> - - <div class="Value"> - <h2>Value</h2> - - <p><dl> - The estimated limit of quantification for a model used for calibration. -</dl></p> - - </div> - - <div class="Description"> - <h2>Description</h2> - - <p>The limit of quantification is the x value, where the relative error - of the quantification given the calibration model reaches a prespecified - value 1/k. Thus, it is the solution of the equation - $$L = k c(L)$$ - where c(L) is half of the length of the confidence interval at the limit L - (DIN 32645, equivalent to ISO 11843). c(L) is internally estimated by - <code><a href='inverse.predict.html'>inverse.predict</a></code>, and L is obtained by iteration.</p> - - </div> - - <div class="Note"> - <h2>Note</h2> - - <p>- IUPAC recommends to base the LOQ on the standard deviation of the signal - where x = 0. - - The calculation of a LOQ based on weighted regression is non-standard - and therefore not tested. Feedback is welcome.</p> - - </div> - - <h2 id="examples">Examples</h2> - <pre class="examples"><div class='input'><span class="functioncall"><a href='http://www.rdocumentation.org/packages/utils/topics/data'>data</a></span><span class="keyword">(</span><span class="symbol">massart97ex3</span><span class="keyword">)</span> -<span class="functioncall"><a href='http://www.rdocumentation.org/packages/base/topics/attach'>attach</a></span><span class="keyword">(</span><span class="symbol">massart97ex3</span><span class="keyword">)</span> -<span class="symbol">m</span> <span class="assignement"><-</span> <span class="functioncall"><a href='http://www.rdocumentation.org/packages/stats/topics/lm'>lm</a></span><span class="keyword">(</span><span class="symbol">y</span> <span class="keyword">~</span> <span class="symbol">x</span><span class="keyword">)</span> -<span class="functioncall"><a href='loq.html'>loq</a></span><span class="keyword">(</span><span class="symbol">m</span><span class="keyword">)</span></div> -<div class='output'>$x -[1] 13.97764 - -$y - 1 -30.6235 - -</div> -<div class='input'> -<span class="comment"># We can get better by using replicate measurements</span> -<span class="functioncall"><a href='loq.html'>loq</a></span><span class="keyword">(</span><span class="symbol">m</span><span class="keyword">,</span> <span class="argument">n</span> <span class="argument">=</span> <span class="number">3</span><span class="keyword">)</span></div> -<div class='output'>$x -[1] 9.971963 - -$y - 1 -22.68539 - -</div></pre> - </div> - <div class="span4 sidebar"> - <!-- <ul> - <li>loq</li><li>loq.lm</li><li>loq.rlm</li><li>loq.default</li> - </ul> - <ul> - <li>manip</li> - </ul> --> - - <h2>See also</h2> - <p>Examples for <code><a href='din32645.html'>din32645</a></code></p> - - - - - </div> -</div> - - <footer> - <p class="pull-right"><a href="#">Back to top</a></p> -<p>Built by <a href="https://github.com/hadley/staticdocs">staticdocs</a>. Styled with <a href="https://getbootstrap.com/2.0.4/">bootstrap</a>.</p> - </footer> - </div> - </body> -</html>
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