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diff --git a/inst/web/massart97ex3.html b/inst/web/massart97ex3.html new file mode 100644 index 0000000..9f94ed8 --- /dev/null +++ b/inst/web/massart97ex3.html @@ -0,0 +1,198 @@ +<!DOCTYPE html> +<html lang="en"> + <head> + <meta charset="utf-8"> +<title>massart97ex3. chemCal 0.1-35.900</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="#">chemCal 0.1-35.900</a> + <div class="nav"> + <ul class="nav"> + <li><a href="index.html"><i class="icon-home icon-white"></i> Index</a></li> + </ul> + </div> + </div> + </div> +</div> + + <div class="container"> + <header> + + </header> + + <h1>Calibration data from Massart et al. (1997), example 3</h1> + +<div class="row"> + <div class="span8"> + <h2>Usage</h2> + <pre><div>data(massart97ex3)</div></pre> + + <div class="Description"> + <h2>Description</h2> + + <p>Sample dataset from p. 188 to test the package.</p> + + </div> + + <div class="Format"> + <h2>Format</h2> + + <p>A dataframe containing 6 levels of x values with 5 + observations of y for each level.</p> + + </div> + + <div class="Source"> + <h2>Source</h2> + + <p>Massart, L.M, Vandenginste, B.G.M., Buydens, L.M.C., De Jong, S., Lewi, P.J., + Smeyers-Verbeke, J. (1997) Handbook of Chemometrics and Qualimetrics: Part A, + Chapter 8.</p> + + </div> + + <h2 id="examples">Examples</h2> + <pre class="examples"><div class='input'>data(massart97ex3) +attach(massart97ex3) +</div> +<strong class='message'>Die folgenden Objekte sind maskiert von massart97ex3 (pos = 3): + + x, y +</strong> +<div class='input'>yx <- split(y, x) +ybar <- sapply(yx, mean) +s <- round(sapply(yx, sd), digits = 2) +w <- round(1 / (s^2), digits = 3) +weights <- w[factor(x)] +m <- lm(y ~ x, w = weights) +calplot(m) +</div> +<strong class='warning'>Warning message: +Assuming constant prediction variance even though model fit is weighted +</strong> +<p><img src='massart97ex3-5.png' alt='' width='540' height='400' /></p> +<div class='input'> +# The following concords with the book p. 200 +inverse.predict(m, 15, ws = 1.67) # 5.9 +- 2.5 +</div> +<div class='output'>$Prediction +[1] 5.865367 + +$`Standard Error` +[1] 0.8926109 + +$Confidence +[1] 2.478285 + +$`Confidence Limits` +[1] 3.387082 8.343652 + +</div> +<div class='input'>inverse.predict(m, 90, ws = 0.145) # 44.1 +- 7.9 +</div> +<div class='output'>$Prediction +[1] 44.06025 + +$`Standard Error` +[1] 2.829162 + +$Confidence +[1] 7.855012 + +$`Confidence Limits` +[1] 36.20523 51.91526 + +</div> +<div class='input'> +# The LOD is only calculated for models from unweighted regression +# with this version of chemCal +m0 <- lm(y ~ x) +lod(m0) +</div> +<div class='output'>$x +[1] 5.407085 + +$y + 1 +13.63911 + +</div> +<div class='input'> +# Limit of quantification from unweighted regression +loq(m0) +</div> +<div class='output'>$x +[1] 13.97764 + +$y + 1 +30.6235 + +</div> +<div class='input'> +# For calculating the limit of quantification from a model from weighted +# regression, we need to supply weights, internally used for inverse.predict +# If we are not using a variance function, we can use the weight from +# the above example as a first approximation (x = 15 is close to our +# loq approx 14 from above). +loq(m, w.loq = 1.67) +</div> +<div class='output'>$x +[1] 7.346195 + +$y + 1 +17.90777 + +</div> +<div class='input'># The weight for the loq should therefore be derived at x = 7.3 instead +# of 15, but the graphical procedure of Massart (p. 201) to derive the +# variances on which the weights are based is quite inaccurate anyway. +</div></pre> + </div> + <div class="span4"> + <!-- <ul> + <li>massart97ex3</li> + </ul> + <ul> + <li>datasets</li> + </ul> --> + + + </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="http://twitter.github.com/bootstrap">bootstrap</a>.</p> + </footer> + </div> + </body> +</html>
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