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| author | Johannes Ranke <jranke@uni-bremen.de> | 2017-03-06 17:00:48 +0100 |
|---|---|---|
| committer | Johannes Ranke <jranke@uni-bremen.de> | 2017-03-06 17:00:48 +0100 |
| commit | 73e650114af77582238abf5273e63005e0b2287e (patch) | |
| tree | e0effa0124a713738c850aa47acc54d1b82318d8 /docs/reference/inverse.predict.html | |
| parent | fcb3332b7b186639cce940696057a2b6dd2c5cca (diff) | |
Static documentation now built by pkgdown::build_site()
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| -rw-r--r-- | docs/reference/inverse.predict.html | 211 |
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diff --git a/docs/reference/inverse.predict.html b/docs/reference/inverse.predict.html new file mode 100644 index 0000000..60d169c --- /dev/null +++ b/docs/reference/inverse.predict.html @@ -0,0 +1,211 @@ +<!-- Generated by pkgdown: do not edit by hand --> +<!DOCTYPE html> +<html> + <head> + <meta charset="utf-8"> +<meta http-equiv="X-UA-Compatible" content="IE=edge"> +<meta name="viewport" content="width=device-width, initial-scale=1.0"> + +<title>Predict x from y for a linear calibration — inverse.predict • chemCal</title> + +<!-- jquery --> +<script src="https://code.jquery.com/jquery-3.1.0.min.js" integrity="sha384-nrOSfDHtoPMzJHjVTdCopGqIqeYETSXhZDFyniQ8ZHcVy08QesyHcnOUpMpqnmWq" crossorigin="anonymous"></script> +<!-- Bootstrap --> + +<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"> +<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script> + +<!-- Font Awesome icons --> +<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css" rel="stylesheet" integrity="sha384-T8Gy5hrqNKT+hzMclPo118YTQO6cYprQmhrYwIiQ/3axmI1hQomh7Ud2hPOy8SP1" crossorigin="anonymous"> + + +<!-- pkgdown --> +<link href="../pkgdown.css" rel="stylesheet"> +<script src="../jquery.sticky-kit.min.js"></script> +<script src="../pkgdown.js"></script> + +<!-- mathjax --> +<script src='https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML'></script> + +<!--[if lt IE 9]> +<script src="https://oss.maxcdn.com/html5shiv/3.7.3/html5shiv.min.js"></script> +<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script> +<![endif]--> + </head> + + <body> + <div class="container template-reference-topic"> + <header> + <div class="navbar navbar-default navbar-fixed-top" role="navigation"> + <div class="container"> + <div class="navbar-header"> + <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar"> + <span class="icon-bar"></span> + <span class="icon-bar"></span> + <span class="icon-bar"></span> + </button> + <a class="navbar-brand" href="../index.html">chemCal</a> + </div> + <div id="navbar" class="navbar-collapse collapse"> + <ul class="nav navbar-nav"> + <li> + <a href="../reference/index.html">Reference</a> +</li> +<li> + <a href="../articles/index.html">Articles</a> +</li> + </ul> + + <ul class="nav navbar-nav navbar-right"> + + </ul> + </div><!--/.nav-collapse --> + </div><!--/.container --> +</div><!--/.navbar --> + + + </header> + + <div class="row"> + <div class="col-md-9 contents"> + <div class="page-header"> + <h1>Predict x from y for a linear calibration</h1> + </div> + + + <p>This function predicts x values using a univariate linear model that has been + generated for the purpose of calibrating a measurement method. Prediction + intervals are given at the specified confidence level. + The calculation method was taken from Massart et al. (1997). In particular, + Equations 8.26 and 8.28 were combined in order to yield a general treatment + of inverse prediction for univariate linear models, taking into account + weights that have been used to create the linear model, and at the same + time providing the possibility to specify a precision in sample measurements + differing from the precision in standard samples used for the calibration. + This is elaborated in the package vignette.</p> + + + <pre>inverse.predict(object, newdata, …, + ws, alpha=0.05, var.s = "auto")</pre> + + <h2 class="hasAnchor" id="arguments"><a class="anchor" href="#arguments"></a> Arguments</h2> + <dl class="dl-horizontal"> + <dt>object</dt> + <dd> + A univariate model object of class <code>lm</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>. + </dd> + <dt>newdata</dt> + <dd> + A vector of observed y values for one sample. + </dd> + <dt>…</dt> + <dd> + Placeholder for further arguments that might be needed by + future implementations. + </dd> + <dt>ws</dt> + <dd> + The weight attributed to the sample. This argument is obligatory + if <code>object</code> has weights. + </dd> + <dt>alpha</dt> + <dd> + The error tolerance level for the confidence interval to be reported. + </dd> + <dt>var.s</dt> + <dd> + The estimated variance of the sample measurements. The default is to take + the residual standard error from the calibration and to adjust it + using <code>ws</code>, if applicable. This means that <code>var.s</code> + overrides <code>ws</code>. + </dd> + </dl> + + <h2 class="hasAnchor" id="value"><a class="anchor" href="#value"></a>Value</h2> + + <p>A list containing the predicted x value, its standard error and a + confidence interval.</p> + + <h2 class="hasAnchor" id="note"><a class="anchor" href="#note"></a>Note</h2> + + <p>The function was validated with examples 7 and 8 from Massart et al. (1997).</p> + + <h2 class="hasAnchor" id="references"><a class="anchor" href="#references"></a>References</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, + p. 200</p> + + + <h2 class="hasAnchor" id="examples"><a class="anchor" href="#examples"></a>Examples</h2> + <pre class="examples"><div class='input'><span class='co'># This is example 7 from Chapter 8 in Massart et al. (1997)</span> +<span class='fu'>data</span>(<span class='no'>massart97ex1</span>) +<span class='no'>m</span> <span class='kw'><-</span> <span class='fu'>lm</span>(<span class='no'>y</span> ~ <span class='no'>x</span>, <span class='kw'>data</span> <span class='kw'>=</span> <span class='no'>massart97ex1</span>) +<span class='fu'>inverse.predict</span>(<span class='no'>m</span>, <span class='fl'>15</span>) <span class='co'># 6.1 +- 4.9</span></div><div class='output co'>#> $Prediction +#> [1] 6.09381 +#> +#> $`Standard Error` +#> [1] 1.767278 +#> +#> $Confidence +#> [1] 4.906751 +#> +#> $`Confidence Limits` +#> [1] 1.187059 11.000561 +#> </div><div class='input'><span class='fu'>inverse.predict</span>(<span class='no'>m</span>, <span class='fl'>90</span>) <span class='co'># 43.9 +- 4.9</span></div><div class='output co'>#> $Prediction +#> [1] 43.93983 +#> +#> $`Standard Error` +#> [1] 1.767747 +#> +#> $Confidence +#> [1] 4.908053 +#> +#> $`Confidence Limits` +#> [1] 39.03178 48.84788 +#> </div><div class='input'><span class='fu'>inverse.predict</span>(<span class='no'>m</span>, <span class='fu'>rep</span>(<span class='fl'>90</span>,<span class='fl'>5</span>)) <span class='co'># 43.9 +- 3.2</span></div><div class='output co'>#> $Prediction +#> [1] 43.93983 +#> +#> $`Standard Error` +#> [1] 1.141204 +#> +#> $Confidence +#> [1] 3.168489 +#> +#> $`Confidence Limits` +#> [1] 40.77134 47.10832 +#> </div></pre> + </div> + <div class="col-md-3 hidden-xs hidden-sm" id="sidebar"> + <h2>Contents</h2> + <ul class="nav nav-pills nav-stacked"> + <li><a href="#arguments">Arguments</a></li> + + <li><a href="#value">Value</a></li> + + <li><a href="#note">Note</a></li> + + <li><a href="#references">References</a></li> + + <li><a href="#examples">Examples</a></li> + </ul> + + </div> +</div> + + <footer> + <div class="copyright"> + <p>Developed by Johannes Ranke.</p> +</div> + +<div class="pkgdown"> + <p>Site built with <a href="http://hadley.github.io/pkgdown/">pkgdown</a>.</p> +</div> + + </footer> + </div> + + </body> +</html> |