aboutsummaryrefslogtreecommitdiff
path: root/docs/reference/add_err.html
blob: 6fbecd14c107136c3136a64bf3c08e2dbfd08c4e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
<!-- 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." />




<!-- 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-default" data-toggle="tooltip" data-placement="bottom" title="Released version">1.0.3</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