aboutsummaryrefslogblamecommitdiff
path: root/docs/dev/reference/add_err.html
blob: b94cef2973c5b9d462f024c9c090ce3478ef6cb5 (plain) (tree)










































































                                                                                                                                                                                                             
                                                                                                                                             













































                                                                                                                             
                                            
                                             















                                                                                  
                                                                                                                                           







                                                                                                          








                                                                                                                                                                                                                        




















































                                                                                                        

                                                                                      


                                                                                            
                                                                                                                                                                                                                                                                                                                                                            
                                                                                                                                             
                                                                                
                                                                                                                                                                                                                                                                                                                                                                                                                                               

                                                                                                      



                                                                                                                                                                                                                                                                                             

                                                                                                         
                                                                                                                                                                                                                                                                                                                                                                                                                                                        
                                                              
                                                                                                                                                                                                                                                                                                                                                                                                                                                



                                                                                                      

                                                                                                                                                                                                                                                                                                                                                                          
 
                                                                                                                                                                          

                                                                                           
                                                                                                                                                                                                                                                                                                                                                      
                                                                                                    
                                                                                                                                                                                                                                                                                















                                                                 
                                                                                










               
<!-- Generated by pkgdown: do not edit by hand -->
<!DOCTYPE html>
<html lang="en">
  <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>Add normally distributed errors to simulated kinetic degradation data — add_err • mkin</title>


<!-- jquery -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js" integrity="sha256-CSXorXvZcTkaix6Yvo6HppcZGetbYMGWSFlBw8HfCJo=" crossorigin="anonymous"></script>
<!-- Bootstrap -->

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.4.1/css/bootstrap.min.css" integrity="sha256-bZLfwXAP04zRMK2BjiO8iu9pf4FbLqX6zitd+tIvLhE=" crossorigin="anonymous" />

<script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.4.1/js/bootstrap.min.js" integrity="sha256-nuL8/2cJ5NDSSwnKD8VqreErSWHtnEP9E7AySL+1ev4=" crossorigin="anonymous"></script>

<!-- bootstrap-toc -->
<link rel="stylesheet" href="../bootstrap-toc.css">
<script src="../bootstrap-toc.js"></script>

<!-- Font Awesome icons -->
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.12.1/css/all.min.css" integrity="sha256-mmgLkCYLUQbXn0B1SRqzHar6dCnv9oZFPEC1g1cwlkk=" crossorigin="anonymous" />
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.12.1/css/v4-shims.min.css" integrity="sha256-wZjR52fzng1pJHwx4aV2AO3yyTOXrcDW7jBpJtTwVxw=" crossorigin="anonymous" />

<!-- clipboard.js -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.6/clipboard.min.js" integrity="sha256-inc5kl9MA1hkeYUt+EC3BhlIgyp/2jDIyBLS6k3UxPI=" crossorigin="anonymous"></script>

<!-- headroom.js -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/headroom/0.11.0/headroom.min.js" integrity="sha256-AsUX4SJE1+yuDu5+mAVzJbuYNPHj/WroHuZ8Ir/CkE0=" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/headroom/0.11.0/jQuery.headroom.min.js" integrity="sha256-ZX/yNShbjqsohH1k95liqY9Gd8uOiE1S4vZc+9KQ1K4=" crossorigin="anonymous"></script>

<!-- pkgdown -->
<link href="../pkgdown.css" rel="stylesheet">
<script src="../pkgdown.js"></script>




<meta property="og:title" content="Add normally distributed errors to simulated kinetic degradation data — add_err" />
<meta property="og:description" content="Normally distributed errors are added to data predicted for a specific
degradation model using mkinpredict. The variance of the error
may depend on the predicted value and is specified as a standard deviation." />


<meta name="robots" content="noindex">

<!-- mathjax -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js" integrity="sha256-nvJJv9wWKEm88qvoQl9ekL2J+k/RWIsaSScxxlsrv8k=" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/config/TeX-AMS-MML_HTMLorMML.js" integrity="sha256-84DKXVJXs0/F8OTMzX4UR909+jtl4G7SPypPavF+GfA=" crossorigin="anonymous"></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 data-spy="scroll" data-target="#toc">
    <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" aria-expanded="false">
        <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
      <span class="navbar-brand">
        <a class="navbar-link" href="../index.html">mkin</a>
        <span class="version label label-info" data-toggle="tooltip" data-placement="bottom" title="In-development version">1.0.3.9000</span>
      </span>
    </div>

    <div id="navbar" class="navbar-collapse collapse">
      <ul class="nav navbar-nav">
        <li>
  <a href="../reference/index.html">Functions and data</a>
</li>
<li class="dropdown">
  <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">
    Articles
     
    <span class="caret"></span>
  </a>
  <ul class="dropdown-menu" role="menu">
    <li>
      <a href="../articles/mkin.html">Introduction to mkin</a>
    </li>
    <li>
      <a href="../articles/FOCUS_D.html">Example evaluation of FOCUS Example Dataset D</a>
    </li>
    <li>
      <a href="../articles/FOCUS_L.html">Example evaluation of FOCUS Laboratory Data L1 to L3</a>
    </li>
    <li>
      <a href="../articles/web_only/FOCUS_Z.html">Example evaluation of FOCUS Example Dataset Z</a>
    </li>
    <li>
      <a href="../articles/web_only/compiled_models.html">Performance benefit by using compiled model definitions in mkin</a>
    </li>
    <li>
      <a href="../articles/twa.html">Calculation of time weighted average concentrations with mkin</a>
    </li>
    <li>
      <a href="../articles/web_only/NAFTA_examples.html">Example evaluation of NAFTA SOP Attachment examples</a>
    </li>
    <li>
      <a href="../articles/web_only/benchmarks.html">Some benchmark timings</a>
    </li>
  </ul>
</li>
<li>
  <a href="../news/index.html">News</a>
</li>
      </ul>
      <ul class="nav navbar-nav navbar-right">
        <li>
  <a href="https://github.com/jranke/mkin/">
    <span class="fab fa-github fa-lg"></span>
     
  </a>
</li>
      </ul>
      
    </div><!--/.nav-collapse -->
  </div><!--/.container -->
</div><!--/.navbar -->

      

      </header>

<div class="row">
  <div class="col-md-9 contents">
    <div class="page-header">
    <h1>Add normally distributed errors to simulated kinetic degradation data</h1>
    <small class="dont-index">Source: <a href='https://github.com/jranke/mkin/blob/master/R/add_err.R'><code>R/add_err.R</code></a></small>
    <div class="hidden name"><code>add_err.Rd</code></div>
    </div>

    <div class="ref-description">
    <p>Normally distributed errors are added to data predicted for a specific
degradation model using <code><a href='mkinpredict.html'>mkinpredict</a></code>. The variance of the error
may depend on the predicted value and is specified as a standard deviation.</p>
    </div>

    <pre class="usage"><span class='fu'>add_err</span><span class='op'>(</span>
  <span class='va'>prediction</span>,
  <span class='va'>sdfunc</span>,
  secondary <span class='op'>=</span> <span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span><span class='op'>(</span><span class='st'>"M1"</span>, <span class='st'>"M2"</span><span class='op'>)</span>,
  n <span class='op'>=</span> <span class='fl'>10</span>,
  LOD <span class='op'>=</span> <span class='fl'>0.1</span>,
  reps <span class='op'>=</span> <span class='fl'>2</span>,
  digits <span class='op'>=</span> <span class='fl'>1</span>,
  seed <span class='op'>=</span> <span class='cn'>NA</span>
<span class='op'>)</span></pre>

    <h2 class="hasAnchor" id="arguments"><a class="anchor" href="#arguments"></a>Arguments</h2>
    <table class="ref-arguments">
    <colgroup><col class="name" /><col class="desc" /></colgroup>
    <tr>
      <th>prediction</th>
      <td><p>A prediction from a kinetic model as produced by
<code><a href='mkinpredict.html'>mkinpredict</a></code>.</p></td>
    </tr>
    <tr>
      <th>sdfunc</th>
      <td><p>A function taking the predicted value as its only argument and
returning a standard deviation that should be used for generating the
random error terms for this value.</p></td>
    </tr>
    <tr>
      <th>secondary</th>
      <td><p>The names of state variables that should have an initial
value of zero</p></td>
    </tr>
    <tr>
      <th>n</th>
      <td><p>The number of datasets to be generated.</p></td>
    </tr>
    <tr>
      <th>LOD</th>
      <td><p>The limit of detection (LOD). Values that are below the LOD after
adding the random error will be set to NA.</p></td>
    </tr>
    <tr>
      <th>reps</th>
      <td><p>The number of replicates to be generated within the datasets.</p></td>
    </tr>
    <tr>
      <th>digits</th>
      <td><p>The number of digits to which the values will be rounded.</p></td>
    </tr>
    <tr>
      <th>seed</th>
      <td><p>The seed used for the generation of random numbers. If NA, the
seed is not set.</p></td>
    </tr>
    </table>

    <h2 class="hasAnchor" id="value"><a class="anchor" href="#value"></a>Value</h2>

    <p>A list of datasets compatible with <code><a href='mmkin.html'>mmkin</a></code>, i.e. the
components of the list are datasets compatible with <code><a href='mkinfit.html'>mkinfit</a></code>.</p>
    <h2 class="hasAnchor" id="references"><a class="anchor" href="#references"></a>References</h2>

    <p>Ranke J and Lehmann R (2015) To t-test or not to t-test, that is
the question. XV Symposium on Pesticide Chemistry 2-4 September 2015,
Piacenza, Italy
https://jrwb.de/posters/piacenza_2015.pdf</p>
    <h2 class="hasAnchor" id="author"><a class="anchor" href="#author"></a>Author</h2>

    <p>Johannes Ranke</p>

    <h2 class="hasAnchor" id="examples"><a class="anchor" href="#examples"></a>Examples</h2>
    <pre class="examples"><div class='input'>
<span class='co'># The kinetic model</span>
<span class='va'>m_SFO_SFO</span> <span class='op'>&lt;-</span> <span class='fu'><a href='mkinmod.html'>mkinmod</a></span><span class='op'>(</span>parent <span class='op'>=</span> <span class='fu'><a href='mkinmod.html'>mkinsub</a></span><span class='op'>(</span><span class='st'>"SFO"</span>, <span class='st'>"M1"</span><span class='op'>)</span>,
                     M1 <span class='op'>=</span> <span class='fu'><a href='mkinmod.html'>mkinsub</a></span><span class='op'>(</span><span class='st'>"SFO"</span><span class='op'>)</span>, use_of_ff <span class='op'>=</span> <span class='st'>"max"</span><span class='op'>)</span>
</div><div class='output co'>#&gt; <span class='message'>Temporary DLL for differentials generated and loaded</span></div><div class='input'>
<span class='co'># Generate a prediction for a specific set of parameters</span>
<span class='va'>sampling_times</span> <span class='op'>=</span> <span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span><span class='op'>(</span><span class='fl'>0</span>, <span class='fl'>1</span>, <span class='fl'>3</span>, <span class='fl'>7</span>, <span class='fl'>14</span>, <span class='fl'>28</span>, <span class='fl'>60</span>, <span class='fl'>90</span>, <span class='fl'>120</span><span class='op'>)</span>

<span class='co'># This is the prediction used for the "Type 2 datasets" on the Piacenza poster</span>
<span class='co'># from 2015</span>
<span class='va'>d_SFO_SFO</span> <span class='op'>&lt;-</span> <span class='fu'><a href='mkinpredict.html'>mkinpredict</a></span><span class='op'>(</span><span class='va'>m_SFO_SFO</span>,
                         <span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span><span class='op'>(</span>k_parent <span class='op'>=</span> <span class='fl'>0.1</span>, f_parent_to_M1 <span class='op'>=</span> <span class='fl'>0.5</span>,
                           k_M1 <span class='op'>=</span> <span class='fu'><a href='https://rdrr.io/r/base/Log.html'>log</a></span><span class='op'>(</span><span class='fl'>2</span><span class='op'>)</span><span class='op'>/</span><span class='fl'>1000</span><span class='op'>)</span>,
                         <span class='fu'><a href='https://rdrr.io/r/base/c.html'>c</a></span><span class='op'>(</span>parent <span class='op'>=</span> <span class='fl'>100</span>, M1 <span class='op'>=</span> <span class='fl'>0</span><span class='op'>)</span>,
                         <span class='va'>sampling_times</span><span class='op'>)</span>

<span class='co'># Add an error term with a constant (independent of the value) standard deviation</span>
<span class='co'># of 10, and generate three datasets</span>
<span class='va'>d_SFO_SFO_err</span> <span class='op'>&lt;-</span> <span class='fu'>add_err</span><span class='op'>(</span><span class='va'>d_SFO_SFO</span>, <span class='kw'>function</span><span class='op'>(</span><span class='va'>x</span><span class='op'>)</span> <span class='fl'>10</span>, n <span class='op'>=</span> <span class='fl'>3</span>, seed <span class='op'>=</span> <span class='fl'>123456789</span> <span class='op'>)</span>

<span class='co'># Name the datasets for nicer plotting</span>
<span class='fu'><a href='https://rdrr.io/r/base/names.html'>names</a></span><span class='op'>(</span><span class='va'>d_SFO_SFO_err</span><span class='op'>)</span> <span class='op'>&lt;-</span> <span class='fu'><a href='https://rdrr.io/r/base/paste.html'>paste</a></span><span class='op'>(</span><span class='st'>"Dataset"</span>, <span class='fl'>1</span><span class='op'>:</span><span class='fl'>3</span><span class='op'>)</span>

<span class='co'># Name the model in the list of models (with only one member in this case) for</span>
<span class='co'># nicer plotting later on.  Be quiet and use only one core not to offend CRAN</span>
<span class='co'># checks</span>
<span class='co'># \dontrun{</span>
<span class='va'>f_SFO_SFO</span> <span class='op'>&lt;-</span> <span class='fu'><a href='mmkin.html'>mmkin</a></span><span class='op'>(</span><span class='fu'><a href='https://rdrr.io/r/base/list.html'>list</a></span><span class='op'>(</span><span class='st'>"SFO-SFO"</span> <span class='op'>=</span> <span class='va'>m_SFO_SFO</span><span class='op'>)</span>,
                   <span class='va'>d_SFO_SFO_err</span>, cores <span class='op'>=</span> <span class='fl'>1</span>,
                   quiet <span class='op'>=</span> <span class='cn'>TRUE</span><span class='op'>)</span>

<span class='fu'><a href='https://rdrr.io/r/graphics/plot.default.html'>plot</a></span><span class='op'>(</span><span class='va'>f_SFO_SFO</span><span class='op'>)</span>
</div><div class='img'><img src='add_err-1.png' alt='' width='700' height='433' /></div><div class='input'>
<span class='co'># We would like to inspect the fit for dataset 3 more closely</span>
<span class='co'># Using double brackets makes the returned object an mkinfit object</span>
<span class='co'># instead of a list of mkinfit objects, so plot.mkinfit is used</span>
<span class='fu'><a href='https://rdrr.io/r/graphics/plot.default.html'>plot</a></span><span class='op'>(</span><span class='va'>f_SFO_SFO</span><span class='op'>[[</span><span class='fl'>3</span><span class='op'>]</span><span class='op'>]</span>, show_residuals <span class='op'>=</span> <span class='cn'>TRUE</span><span class='op'>)</span>
</div><div class='img'><img src='add_err-2.png' alt='' width='700' height='433' /></div><div class='input'>
<span class='co'># If we use single brackets, we should give two indices (model and dataset),</span>
<span class='co'># and plot.mmkin is used</span>
<span class='fu'><a href='https://rdrr.io/r/graphics/plot.default.html'>plot</a></span><span class='op'>(</span><span class='va'>f_SFO_SFO</span><span class='op'>[</span><span class='fl'>1</span>, <span class='fl'>3</span><span class='op'>]</span><span class='op'>)</span>
</div><div class='img'><img src='add_err-3.png' alt='' width='700' height='433' /></div><div class='input'><span class='co'># }</span>

</div></pre>
  </div>
  <div class="col-md-3 hidden-xs hidden-sm" id="pkgdown-sidebar">
    <nav id="toc" data-toggle="toc" class="sticky-top">
      <h2 data-toc-skip>Contents</h2>
    </nav>
  </div>
</div>


      <footer>
      <div class="copyright">
  <p>Developed by Johannes Ranke.</p>
</div>

<div class="pkgdown">
  <p>Site built with <a href="https://pkgdown.r-lib.org/">pkgdown</a> 1.6.1.</p>
</div>

      </footer>
   </div>

  


  </body>
</html>


Contact - Imprint