aboutsummaryrefslogtreecommitdiff
path: root/docs/dev/articles/web_only/dimethenamid_2018.html
diff options
context:
space:
mode:
authorJohannes Ranke <jranke@uni-bremen.de>2023-04-16 13:42:23 +0200
committerJohannes Ranke <jranke@uni-bremen.de>2023-04-16 13:42:23 +0200
commit34ec60f1b140d788880d84b70cb62b344f7d74b9 (patch)
tree26196c367f037b69f410363a393dad87b5bff233 /docs/dev/articles/web_only/dimethenamid_2018.html
parent99b4554a1ce657295b1358509110f3d02155a913 (diff)
Complete rebuild of static docs
Diffstat (limited to 'docs/dev/articles/web_only/dimethenamid_2018.html')
-rw-r--r--docs/dev/articles/web_only/dimethenamid_2018.html344
1 files changed, 261 insertions, 83 deletions
diff --git a/docs/dev/articles/web_only/dimethenamid_2018.html b/docs/dev/articles/web_only/dimethenamid_2018.html
index ec7f54d8..eb4a11a5 100644
--- a/docs/dev/articles/web_only/dimethenamid_2018.html
+++ b/docs/dev/articles/web_only/dimethenamid_2018.html
@@ -34,14 +34,14 @@
</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">1.2.2</span>
+ <span class="version label label-info" data-toggle="tooltip" data-placement="bottom" title="In-development version">1.2.3</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>
+ <a href="../../reference/index.html">Reference</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
@@ -53,6 +53,9 @@
<li>
<a href="../../articles/mkin.html">Introduction to mkin</a>
</li>
+ <li class="divider">
+ </li>
+<li class="dropdown-header">Example evaluations with (generalised) nonlinear least squares</li>
<li>
<a href="../../articles/FOCUS_D.html">Example evaluation of FOCUS Example Dataset D</a>
</li>
@@ -60,22 +63,31 @@
<a href="../../articles/FOCUS_L.html">Example evaluation of FOCUS Laboratory Data L1 to L3</a>
</li>
<li>
- <a href="../../articles/web_only/dimethenamid_2018.html">Example evaluations of dimethenamid data from 2018 with nonlinear mixed-effects models</a>
+ <a href="../../articles/web_only/FOCUS_Z.html">Example evaluation of FOCUS Example Dataset Z</a>
+ </li>
+ <li class="divider">
</li>
+<li class="dropdown-header">Example evaluations with hierarchical models (nonlinear mixed-effects models)</li>
<li>
- <a href="../../articles/web_only/multistart.html">Short demo of the multistart method</a>
+ <a href="../../articles/prebuilt/2022_dmta_parent.html">Testing hierarchical parent degradation kinetics with residue data on dimethenamid and dimethenamid-P</a>
</li>
<li>
- <a href="../../articles/web_only/compiled_models.html">Performance benefit by using compiled model definitions in mkin</a>
+ <a href="../../articles/prebuilt/2022_dmta_pathway.html">Testing hierarchical pathway kinetics with residue data on dimethenamid and dimethenamid-P</a>
</li>
<li>
- <a href="../../articles/web_only/FOCUS_Z.html">Example evaluation of FOCUS Example Dataset Z</a>
+ <a href="../../articles/prebuilt/2022_cyan_pathway.html">Testing hierarchical pathway kinetics with residue data on cyantraniliprole</a>
</li>
<li>
- <a href="../../articles/twa.html">Calculation of time weighted average concentrations with mkin</a>
+ <a href="../../articles/web_only/dimethenamid_2018.html">Comparison of saemix and nlme evaluations of dimethenamid data from 2018</a>
</li>
<li>
- <a href="../../articles/web_only/NAFTA_examples.html">Example evaluation of NAFTA SOP Attachment examples</a>
+ <a href="../../articles/web_only/multistart.html">Short demo of the multistart method</a>
+ </li>
+ <li class="divider">
+ </li>
+<li class="dropdown-header">Performance</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/web_only/benchmarks.html">Benchmark timings for mkin</a>
@@ -83,6 +95,15 @@
<li>
<a href="../../articles/web_only/saem_benchmarks.html">Benchmark timings for saem.mmkin</a>
</li>
+ <li class="divider">
+ </li>
+<li class="dropdown-header">Miscellaneous</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>
</ul>
</li>
<li>
@@ -106,13 +127,16 @@
- </header><script src="dimethenamid_2018_files/accessible-code-block-0.0.1/empty-anchor.js"></script><div class="row">
+ </header><div class="row">
<div class="col-md-9 contents">
<div class="page-header toc-ignore">
- <h1 data-toc-skip>Example evaluations of the dimethenamid data from 2018</h1>
- <h4 data-toc-skip class="author">Johannes Ranke</h4>
+ <h1 data-toc-skip>Example evaluations of the dimethenamid data
+from 2018</h1>
+ <h4 data-toc-skip class="author">Johannes
+Ranke</h4>
- <h4 data-toc-skip class="date">Last change 1 July 2022, built on 24 Nov 2022</h4>
+ <h4 data-toc-skip class="date">Last change 1 July 2022,
+built on 16 Apr 2023</h4>
<small class="dont-index">Source: <a href="https://github.com/jranke/mkin/blob/HEAD/vignettes/web_only/dimethenamid_2018.rmd" class="external-link"><code>vignettes/web_only/dimethenamid_2018.rmd</code></a></small>
<div class="hidden name"><code>dimethenamid_2018.rmd</code></div>
@@ -121,19 +145,48 @@
-<p><a href="http://www.jrwb.de" class="external-link">Wissenschaftlicher Berater, Kronacher Str. 12, 79639 Grenzach-Wyhlen, Germany</a></p>
+<p><a href="http://www.jrwb.de" class="external-link">Wissenschaftlicher Berater, Kronacher
+Str. 12, 79639 Grenzach-Wyhlen, Germany</a></p>
<div class="section level2">
<h2 id="introduction">Introduction<a class="anchor" aria-label="anchor" href="#introduction"></a>
</h2>
-<p>A first analysis of the data analysed here was presented in a recent journal article on nonlinear mixed-effects models in degradation kinetics <span class="citation">(Ranke et al. 2021)</span>. That analysis was based on the <code>nlme</code> package and a development version of the <code>saemix</code> package that was unpublished at the time. Meanwhile, version 3.0 of the <code>saemix</code> package is available from the CRAN repository. Also, it turned out that there was an error in the handling of the Borstel data in the mkin package at the time, leading to the duplication of a few data points from that soil. The dataset in the mkin package has been corrected, and the interface to <code>saemix</code> in the mkin package has been updated to use the released version.</p>
-<p>This vignette is intended to present an up to date analysis of the data, using the corrected dataset and released versions of <code>mkin</code> and <code>saemix</code>.</p>
+<p>A first analysis of the data analysed here was presented in a recent
+journal article on nonlinear mixed-effects models in degradation
+kinetics <span class="citation">(Ranke et al. 2021)</span>. That
+analysis was based on the <code>nlme</code> package and a development
+version of the <code>saemix</code> package that was unpublished at the
+time. Meanwhile, version 3.0 of the <code>saemix</code> package is
+available from the CRAN repository. Also, it turned out that there was
+an error in the handling of the Borstel data in the mkin package at the
+time, leading to the duplication of a few data points from that soil.
+The dataset in the mkin package has been corrected, and the interface to
+<code>saemix</code> in the mkin package has been updated to use the
+released version.</p>
+<p>This vignette is intended to present an up to date analysis of the
+data, using the corrected dataset and released versions of
+<code>mkin</code> and <code>saemix</code>.</p>
</div>
<div class="section level2">
<h2 id="data">Data<a class="anchor" aria-label="anchor" href="#data"></a>
</h2>
-<p>Residue data forming the basis for the endpoints derived in the conclusion on the peer review of the pesticide risk assessment of dimethenamid-P published by the European Food Safety Authority (EFSA) in 2018 <span class="citation">(EFSA 2018)</span> were transcribed from the risk assessment report <span class="citation">(Rapporteur Member State Germany, Co-Rapporteur Member State Bulgaria 2018)</span> which can be downloaded from the Open EFSA repository <a href="https://open.efsa.europa.eu" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>.</p>
-<p>The data are <a href="https://pkgdown.jrwb.de/mkin/reference/dimethenamid_2018.html">available in the mkin package</a>. The following code (hidden by default, please use the button to the right to show it) treats the data available for the racemic mixture dimethenamid (DMTA) and its enantiomer dimethenamid-P (DMTAP) in the same way, as no difference between their degradation behaviour was identified in the EU risk assessment. The observation times of each dataset are multiplied with the corresponding normalisation factor also available in the dataset, in order to make it possible to describe all datasets with a single set of parameters.</p>
-<p>Also, datasets observed in the same soil are merged, resulting in dimethenamid (DMTA) data from six soils.</p>
+<p>Residue data forming the basis for the endpoints derived in the
+conclusion on the peer review of the pesticide risk assessment of
+dimethenamid-P published by the European Food Safety Authority (EFSA) in
+2018 <span class="citation">(EFSA 2018)</span> were transcribed from the
+risk assessment report <span class="citation">(Rapporteur Member State
+Germany, Co-Rapporteur Member State Bulgaria 2018)</span> which can be
+downloaded from the Open EFSA repository <a href="https://open.efsa.europa.eu" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>.</p>
+<p>The data are <a href="https://pkgdown.jrwb.de/mkin/reference/dimethenamid_2018.html">available
+in the mkin package</a>. The following code (hidden by default, please
+use the button to the right to show it) treats the data available for
+the racemic mixture dimethenamid (DMTA) and its enantiomer
+dimethenamid-P (DMTAP) in the same way, as no difference between their
+degradation behaviour was identified in the EU risk assessment. The
+observation times of each dataset are multiplied with the corresponding
+normalisation factor also available in the dataset, in order to make it
+possible to describe all datasets with a single set of parameters.</p>
+<p>Also, datasets observed in the same soil are merged, resulting in
+dimethenamid (DMTA) data from six soils.</p>
<div class="sourceCode" id="cb1"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://pkgdown.jrwb.de/mkin/">mkin</a></span>, quietly <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span>
<span><span class="va">dmta_ds</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">lapply</a></span><span class="op">(</span><span class="fl">1</span><span class="op">:</span><span class="fl">7</span>, <span class="kw">function</span><span class="op">(</span><span class="va">i</span><span class="op">)</span> <span class="op">{</span></span>
@@ -150,34 +203,60 @@
<div class="section level2">
<h2 id="parent-degradation">Parent degradation<a class="anchor" aria-label="anchor" href="#parent-degradation"></a>
</h2>
-<p>We evaluate the observed degradation of the parent compound using simple exponential decline (SFO) and biexponential decline (DFOP), using constant variance (const) and a two-component variance (tc) as error models.</p>
+<p>We evaluate the observed degradation of the parent compound using
+simple exponential decline (SFO) and biexponential decline (DFOP), using
+constant variance (const) and a two-component variance (tc) as error
+models.</p>
<div class="section level3">
<h3 id="separate-evaluations">Separate evaluations<a class="anchor" aria-label="anchor" href="#separate-evaluations"></a>
</h3>
-<p>As a first step, to get a visual impression of the fit of the different models, we do separate evaluations for each soil using the mmkin function from the mkin package:</p>
+<p>As a first step, to get a visual impression of the fit of the
+different models, we do separate evaluations for each soil using the
+mmkin function from the mkin package:</p>
<div class="sourceCode" id="cb2"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_mkin_const</span> <span class="op">&lt;-</span> <span class="fu"><a href="../../reference/mmkin.html">mmkin</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"DFOP"</span><span class="op">)</span>, <span class="va">dmta_ds</span>,</span>
<span> error_model <span class="op">=</span> <span class="st">"const"</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span>
<span><span class="va">f_parent_mkin_tc</span> <span class="op">&lt;-</span> <span class="fu"><a href="../../reference/mmkin.html">mmkin</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"DFOP"</span><span class="op">)</span>, <span class="va">dmta_ds</span>,</span>
<span> error_model <span class="op">=</span> <span class="st">"tc"</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div>
-<p>The plot of the individual SFO fits shown below suggests that at least in some datasets the degradation slows down towards later time points, and that the scatter of the residuals error is smaller for smaller values (panel to the right):</p>
+<p>The plot of the individual SFO fits shown below suggests that at
+least in some datasets the degradation slows down towards later time
+points, and that the scatter of the residuals error is smaller for
+smaller values (panel to the right):</p>
<div class="sourceCode" id="cb3"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_sfo_const-1.png" width="700"></p>
-<p>Using biexponential decline (DFOP) results in a slightly more random scatter of the residuals:</p>
+<p>Using biexponential decline (DFOP) results in a slightly more random
+scatter of the residuals:</p>
<div class="sourceCode" id="cb4"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_const-1.png" width="700"></p>
-<p>The population curve (bold line) in the above plot results from taking the mean of the individual transformed parameters, i.e. of log k1 and log k2, as well as of the logit of the g parameter of the DFOP model). Here, this procedure does not result in parameters that represent the degradation well, because in some datasets the fitted value for k2 is extremely close to zero, leading to a log k2 value that dominates the average. This is alleviated if only rate constants that pass the t-test for significant difference from zero (on the untransformed scale) are considered in the averaging:</p>
+<p>The population curve (bold line) in the above plot results from
+taking the mean of the individual transformed parameters, i.e. of log k1
+and log k2, as well as of the logit of the g parameter of the DFOP
+model). Here, this procedure does not result in parameters that
+represent the degradation well, because in some datasets the fitted
+value for k2 is extremely close to zero, leading to a log k2 value that
+dominates the average. This is alleviated if only rate constants that
+pass the t-test for significant difference from zero (on the
+untransformed scale) are considered in the averaging:</p>
<div class="sourceCode" id="cb5"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span>, test_log_parms <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_const_test-1.png" width="700"></p>
-<p>While this is visually much more satisfactory, such an average procedure could introduce a bias, as not all results from the individual fits enter the population curve with the same weight. This is where nonlinear mixed-effects models can help out by treating all datasets with equally by fitting a parameter distribution model together with the degradation model and the error model (see below).</p>
-<p>The remaining trend of the residuals to be higher for higher predicted residues is reduced by using the two-component error model:</p>
+<p>While this is visually much more satisfactory, such an average
+procedure could introduce a bias, as not all results from the individual
+fits enter the population curve with the same weight. This is where
+nonlinear mixed-effects models can help out by treating all datasets
+with equally by fitting a parameter distribution model together with the
+degradation model and the error model (see below).</p>
+<p>The remaining trend of the residuals to be higher for higher
+predicted residues is reduced by using the two-component error
+model:</p>
<div class="sourceCode" id="cb6"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="fu"><a href="../../reference/mixed.html">mixed</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span>, test_log_parms <span class="op">=</span> <span class="cn">TRUE</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_mkin_dfop_tc_test-1.png" width="700"></p>
-<p>However, note that in the case of using this error model, the fits to the Flaach and BBA 2.3 datasets appear to be ill-defined, indicated by the fact that they did not converge:</p>
+<p>However, note that in the case of using this error model, the fits to
+the Flaach and BBA 2.3 datasets appear to be ill-defined, indicated by
+the fact that they did not converge:</p>
<div class="sourceCode" id="cb7"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span></code></pre></div>
<pre><code>&lt;mmkin&gt; object
@@ -194,19 +273,46 @@ OK: No warnings</code></pre>
<div class="section level3">
<h3 id="nonlinear-mixed-effects-models">Nonlinear mixed-effects models<a class="anchor" aria-label="anchor" href="#nonlinear-mixed-effects-models"></a>
</h3>
-<p>Instead of taking a model selection decision for each of the individual fits, we fit nonlinear mixed-effects models (using different fitting algorithms as implemented in different packages) and do model selection using all available data at the same time. In order to make sure that these decisions are not unduly influenced by the type of algorithm used, by implementation details or by the use of wrong control parameters, we compare the model selection results obtained with different R packages, with different algorithms and checking control parameters.</p>
+<p>Instead of taking a model selection decision for each of the
+individual fits, we fit nonlinear mixed-effects models (using different
+fitting algorithms as implemented in different packages) and do model
+selection using all available data at the same time. In order to make
+sure that these decisions are not unduly influenced by the type of
+algorithm used, by implementation details or by the use of wrong control
+parameters, we compare the model selection results obtained with
+different R packages, with different algorithms and checking control
+parameters.</p>
<div class="section level4">
<h4 id="nlme">nlme<a class="anchor" aria-label="anchor" href="#nlme"></a>
</h4>
-<p>The nlme package was the first R extension providing facilities to fit nonlinear mixed-effects models. We would like to do model selection from all four combinations of degradation models and error models based on the AIC. However, fitting the DFOP model with constant variance and using default control parameters results in an error, signalling that the maximum number of 50 iterations was reached, potentially indicating overparameterisation. Nevertheless, the algorithm converges when the two-component error model is used in combination with the DFOP model. This can be explained by the fact that the smaller residues observed at later sampling times get more weight when using the two-component error model which will counteract the tendency of the algorithm to try parameter combinations unsuitable for fitting these data.</p>
+<p>The nlme package was the first R extension providing facilities to
+fit nonlinear mixed-effects models. We would like to do model selection
+from all four combinations of degradation models and error models based
+on the AIC. However, fitting the DFOP model with constant variance and
+using default control parameters results in an error, signalling that
+the maximum number of 50 iterations was reached, potentially indicating
+overparameterisation. Nevertheless, the algorithm converges when the
+two-component error model is used in combination with the DFOP model.
+This can be explained by the fact that the smaller residues observed at
+later sampling times get more weight when using the two-component error
+model which will counteract the tendency of the algorithm to try
+parameter combinations unsuitable for fitting these data.</p>
<div class="sourceCode" id="cb9"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://svn.r-project.org/R-packages/trunk/nlme/" class="external-link">nlme</a></span><span class="op">)</span></span>
<span><span class="va">f_parent_nlme_sfo_const</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span></span>
<span><span class="co"># f_parent_nlme_dfop_const &lt;- nlme(f_parent_mkin_const["DFOP", ])</span></span>
<span><span class="va">f_parent_nlme_sfo_tc</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span><span class="op">)</span></span>
<span><span class="va">f_parent_nlme_dfop_tc</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span></code></pre></div>
-<p>Note that a certain degree of overparameterisation is also indicated by a warning obtained when fitting DFOP with the two-component error model (‘false convergence’ in the ‘LME step’ in iteration 3). However, as this warning does not occur in later iterations, and specifically not in the last of the 6 iterations, we can ignore this warning.</p>
-<p>The model comparison function of the nlme package can directly be applied to these fits showing a much lower AIC for the DFOP model fitted with the two-component error model. Also, the likelihood ratio test indicates that this difference is significant as the p-value is below 0.0001.</p>
+<p>Note that a certain degree of overparameterisation is also indicated
+by a warning obtained when fitting DFOP with the two-component error
+model (‘false convergence’ in the ‘LME step’ in iteration 3). However,
+as this warning does not occur in later iterations, and specifically not
+in the last of the 5 iterations, we can ignore this warning.</p>
+<p>The model comparison function of the nlme package can directly be
+applied to these fits showing a much lower AIC for the DFOP model fitted
+with the two-component error model. Also, the likelihood ratio test
+indicates that this difference is significant as the p-value is below
+0.0001.</p>
<div class="sourceCode" id="cb10"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span></span>
<span> <span class="va">f_parent_nlme_sfo_const</span>, <span class="va">f_parent_nlme_sfo_tc</span>, <span class="va">f_parent_nlme_dfop_tc</span></span>
@@ -215,7 +321,10 @@ OK: No warnings</code></pre>
f_parent_nlme_sfo_const 1 5 796.60 811.82 -393.30
f_parent_nlme_sfo_tc 2 6 798.60 816.86 -393.30 1 vs 2 0.00 0.998
f_parent_nlme_dfop_tc 3 10 671.91 702.34 -325.96 2 vs 3 134.69 &lt;.0001</code></pre>
-<p>In addition to these fits, attempts were also made to include correlations between random effects by using the log Cholesky parameterisation of the matrix specifying them. The code used for these attempts can be made visible below.</p>
+<p>In addition to these fits, attempts were also made to include
+correlations between random effects by using the log Cholesky
+parameterisation of the matrix specifying them. The code used for these
+attempts can be made visible below.</p>
<div class="sourceCode" id="cb12"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_nlme_sfo_const_logchol</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>,</span>
<span> random <span class="op">=</span> <span class="fu">nlme</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/nlme/man/pdLogChol.html" class="external-link">pdLogChol</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">DMTA_0</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k_DMTA</span> <span class="op">~</span> <span class="fl">1</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span>
@@ -226,8 +335,12 @@ f_parent_nlme_dfop_tc 3 10 671.91 702.34 -325.96 2 vs 3 134.69 &lt;.0001
<span><span class="va">f_parent_nlme_dfop_tc_logchol</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/nlme/man/nlme.html" class="external-link">nlme</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>,</span>
<span> random <span class="op">=</span> <span class="fu">nlme</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/nlme/man/pdLogChol.html" class="external-link">pdLogChol</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">DMTA_0</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k1</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">log_k2</span> <span class="op">~</span> <span class="fl">1</span>, <span class="va">g_qlogis</span> <span class="op">~</span> <span class="fl">1</span><span class="op">)</span><span class="op">)</span><span class="op">)</span></span>
<span><span class="fu"><a href="https://rdrr.io/r/stats/anova.html" class="external-link">anova</a></span><span class="op">(</span><span class="va">f_parent_nlme_dfop_tc</span>, <span class="va">f_parent_nlme_dfop_tc_logchol</span><span class="op">)</span></span></code></pre></div>
-<p>While the SFO variants converge fast, the additional parameters introduced by this lead to convergence warnings for the DFOP model. The model comparison clearly show that adding correlations between random effects does not improve the fits.</p>
-<p>The selected model (DFOP with two-component error) fitted to the data assuming no correlations between random effects is shown below.</p>
+<p>While the SFO variants converge fast, the additional parameters
+introduced by this lead to convergence warnings for the DFOP model. The
+model comparison clearly show that adding correlations between random
+effects does not improve the fits.</p>
+<p>The selected model (DFOP with two-component error) fitted to the data
+assuming no correlations between random effects is shown below.</p>
<div class="sourceCode" id="cb13"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_nlme_dfop_tc</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/plot_parent_nlme-1.png" width="700"></p>
@@ -235,8 +348,16 @@ f_parent_nlme_dfop_tc 3 10 671.91 702.34 -325.96 2 vs 3 134.69 &lt;.0001
<div class="section level4">
<h4 id="saemix">saemix<a class="anchor" aria-label="anchor" href="#saemix"></a>
</h4>
-<p>The saemix package provided the first Open Source implementation of the Stochastic Approximation to the Expectation Maximisation (SAEM) algorithm. SAEM fits of degradation models can be conveniently performed using an interface to the saemix package available in current development versions of the mkin package.</p>
-<p>The corresponding SAEM fits of the four combinations of degradation and error models are fitted below. As there is no convergence criterion implemented in the saemix package, the convergence plots need to be manually checked for every fit. We define control settings that work well for all the parent data fits shown in this vignette.</p>
+<p>The saemix package provided the first Open Source implementation of
+the Stochastic Approximation to the Expectation Maximisation (SAEM)
+algorithm. SAEM fits of degradation models can be conveniently performed
+using an interface to the saemix package available in current
+development versions of the mkin package.</p>
+<p>The corresponding SAEM fits of the four combinations of degradation
+and error models are fitted below. As there is no convergence criterion
+implemented in the saemix package, the convergence plots need to be
+manually checked for every fit. We define control settings that work
+well for all the parent data fits shown in this vignette.</p>
<div class="sourceCode" id="cb14"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va">saemix</span><span class="op">)</span></span>
<span><span class="va">saemix_control</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/saemix/man/saemixControl.html" class="external-link">saemixControl</a></span><span class="op">(</span>nbiter.saemix <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">800</span>, <span class="fl">300</span><span class="op">)</span>, nb.chains <span class="op">=</span> <span class="fl">15</span>,</span>
@@ -245,19 +366,23 @@ f_parent_nlme_dfop_tc 3 10 671.91 702.34 -325.96 2 vs 3 134.69 &lt;.0001
<span> print <span class="op">=</span> <span class="cn">FALSE</span>, save <span class="op">=</span> <span class="cn">FALSE</span>, save.graphs <span class="op">=</span> <span class="cn">FALSE</span>, displayProgress <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span>
<span><span class="va">saemix_control_10k</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/pkg/saemix/man/saemixControl.html" class="external-link">saemixControl</a></span><span class="op">(</span>nbiter.saemix <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">10000</span>, <span class="fl">300</span><span class="op">)</span>, nb.chains <span class="op">=</span> <span class="fl">15</span>,</span>
<span> print <span class="op">=</span> <span class="cn">FALSE</span>, save <span class="op">=</span> <span class="cn">FALSE</span>, save.graphs <span class="op">=</span> <span class="cn">FALSE</span>, displayProgress <span class="op">=</span> <span class="cn">FALSE</span><span class="op">)</span></span></code></pre></div>
-<p>The convergence plot for the SFO model using constant variance is shown below.</p>
+<p>The convergence plot for the SFO model using constant variance is
+shown below.</p>
<div class="sourceCode" id="cb15"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_sfo_const</span> <span class="op">&lt;-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span>
<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span>
<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_sfo_const-1.png" width="700"></p>
-<p>Obviously the selected number of iterations is sufficient to reach convergence. This can also be said for the SFO fit using the two-component error model.</p>
+<p>Obviously the selected number of iterations is sufficient to reach
+convergence. This can also be said for the SFO fit using the
+two-component error model.</p>
<div class="sourceCode" id="cb16"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_sfo_tc</span> <span class="op">&lt;-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span>
<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span>
<span><span class="fu"><a href="https://rdrr.io/r/base/plot.html" class="external-link">plot</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>, plot.type <span class="op">=</span> <span class="st">"convergence"</span><span class="op">)</span></span></code></pre></div>
<p><img src="dimethenamid_2018_files/figure-html/f_parent_saemix_sfo_tc-1.png" width="700"></p>
-<p>When fitting the DFOP model with constant variance (see below), parameter convergence is not as unambiguous.</p>
+<p>When fitting the DFOP model with constant variance (see below),
+parameter convergence is not as unambiguous.</p>
<div class="sourceCode" id="cb17"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_const</span> <span class="op">&lt;-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_const</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span>
<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span>
@@ -284,13 +409,21 @@ DMTA_0 97.99583 96.50079 99.4909
k1 0.06377 0.03432 0.0932
k2 0.00848 0.00444 0.0125
g 0.95701 0.91313 1.0009
-a.1 1.82141 1.65974 1.9831
-SD.DMTA_0 1.64787 0.45779 2.8379
+a.1 1.82141 1.65122 1.9916
+SD.DMTA_0 1.64787 0.45772 2.8380
SD.k1 0.57439 0.24731 0.9015
-SD.k2 0.03296 -2.50143 2.5673
-SD.g 1.10266 0.32371 1.8816</code></pre>
-<p>While the other parameters converge to credible values, the variance of k2 (<code>omega2.k2</code>) converges to a very small value. The printout of the <code>saem.mmkin</code> model shows that the estimated standard deviation of k2 across the population of soils (<code>SD.k2</code>) is ill-defined, indicating overparameterisation of this model.</p>
-<p>When the DFOP model is fitted with the two-component error model, we also observe that the estimated variance of k2 becomes very small, while being ill-defined, as illustrated by the excessive confidence interval of <code>SD.k2</code>.</p>
+SD.k2 0.03296 -2.50195 2.5679
+SD.g 1.10266 0.32369 1.8816</code></pre>
+<p>While the other parameters converge to credible values, the variance
+of k2 (<code>omega2.k2</code>) converges to a very small value. The
+printout of the <code>saem.mmkin</code> model shows that the estimated
+standard deviation of k2 across the population of soils
+(<code>SD.k2</code>) is ill-defined, indicating overparameterisation of
+this model.</p>
+<p>When the DFOP model is fitted with the two-component error model, we
+also observe that the estimated variance of k2 becomes very small, while
+being ill-defined, as illustrated by the excessive confidence interval
+of <code>SD.k2</code>.</p>
<div class="sourceCode" id="cb20"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc</span> <span class="op">&lt;-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span>, quiet <span class="op">=</span> <span class="cn">TRUE</span>,</span>
<span> control <span class="op">=</span> <span class="va">saemix_control</span>, transformations <span class="op">=</span> <span class="st">"saemix"</span><span class="op">)</span></span>
@@ -325,9 +458,21 @@ SD.DMTA_0 2.06075 0.4187 3.7028
SD.k1 0.59357 0.2561 0.9310
SD.k2 0.00292 -10.2960 10.3019
SD.g 1.05725 0.3808 1.7337</code></pre>
-<p>Doubling the number of iterations in the first phase of the algorithm leads to a slightly lower likelihood, and therefore to slightly higher AIC and BIC values. With even more iterations, the algorithm stops with an error message. This is related to the variance of k2 approximating zero and has been submitted as a <a href="https://github.com/saemixdevelopment/saemixextension/issues/29" class="external-link">bug to the saemix package</a>, as the algorithm does not converge in this case.</p>
-<p>An alternative way to fit DFOP in combination with the two-component error model is to use the model formulation with transformed parameters as used per default in mkin. When using this option, convergence is slower, but eventually the algorithm stops as well with the same error message.</p>
-<p>The four combinations (SFO/const, SFO/tc, DFOP/const and DFOP/tc) and the version with increased iterations can be compared using the model comparison function of the saemix package:</p>
+<p>Doubling the number of iterations in the first phase of the algorithm
+leads to a slightly lower likelihood, and therefore to slightly higher
+AIC and BIC values. With even more iterations, the algorithm stops with
+an error message. This is related to the variance of k2 approximating
+zero and has been submitted as a <a href="https://github.com/saemixdevelopment/saemixextension/issues/29" class="external-link">bug
+to the saemix package</a>, as the algorithm does not converge in this
+case.</p>
+<p>An alternative way to fit DFOP in combination with the two-component
+error model is to use the model formulation with transformed parameters
+as used per default in mkin. When using this option, convergence is
+slower, but eventually the algorithm stops as well with the same error
+message.</p>
+<p>The four combinations (SFO/const, SFO/tc, DFOP/const and DFOP/tc) and
+the version with increased iterations can be compared using the model
+comparison function of the saemix package:</p>
<div class="sourceCode" id="cb23"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">AIC_parent_saemix</span> <span class="op">&lt;-</span> <span class="fu">saemix</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/saemix/man/compare.saemix.html" class="external-link">compare.saemix</a></span><span class="op">(</span></span>
<span> <span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>,</span>
@@ -346,7 +491,10 @@ SFO tc 798.38 797.13
DFOP const 705.75 703.88
DFOP tc 665.65 663.57
DFOP tc more iterations 665.88 663.80</code></pre>
-<p>In order to check the influence of the likelihood calculation algorithms implemented in saemix, the likelihood from Gaussian quadrature is added to the best fit, and the AIC values obtained from the three methods are compared.</p>
+<p>In order to check the influence of the likelihood calculation
+algorithms implemented in saemix, the likelihood from Gaussian
+quadrature is added to the best fit, and the AIC values obtained from
+the three methods are compared.</p>
<div class="sourceCode" id="cb27"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span> <span class="op">&lt;-</span></span>
<span> <span class="fu">saemix</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/saemix/man/llgq.saemix.html" class="external-link">llgq.saemix</a></span><span class="op">(</span><span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span><span class="op">)</span></span>
@@ -358,9 +506,19 @@ DFOP tc more iterations 665.88 663.80</code></pre>
<span><span class="fu"><a href="https://rdrr.io/r/base/print.html" class="external-link">print</a></span><span class="op">(</span><span class="va">AIC_parent_saemix_methods</span><span class="op">)</span></span></code></pre></div>
<pre><code> is gq lin
665.65 665.68 665.11 </code></pre>
-<p>The AIC values based on importance sampling and Gaussian quadrature are very similar. Using linearisation is known to be less accurate, but still gives a similar value.</p>
-<p>In order to illustrate that the comparison of the three method depends on the degree of convergence obtained in the fit, the same comparison is shown below for the fit using the defaults for the number of iterations and the number of MCMC chains.</p>
-<p>When using OpenBlas for linear algebra, there is a large difference in the values obtained with Gaussian quadrature, so the larger number of iterations makes a lot of difference. When using the LAPACK version coming with Debian Bullseye, the AIC based on Gaussian quadrature is almost the same as the one obtained with the other methods, also when using defaults for the fit.</p>
+<p>The AIC values based on importance sampling and Gaussian quadrature
+are very similar. Using linearisation is known to be less accurate, but
+still gives a similar value.</p>
+<p>In order to illustrate that the comparison of the three method
+depends on the degree of convergence obtained in the fit, the same
+comparison is shown below for the fit using the defaults for the number
+of iterations and the number of MCMC chains.</p>
+<p>When using OpenBlas for linear algebra, there is a large difference
+in the values obtained with Gaussian quadrature, so the larger number of
+iterations makes a lot of difference. When using the LAPACK version
+coming with Debian Bullseye, the AIC based on Gaussian quadrature is
+almost the same as the one obtained with the other methods, also when
+using defaults for the fit.</p>
<div class="sourceCode" id="cb29"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">f_parent_saemix_dfop_tc_defaults</span> <span class="op">&lt;-</span> <span class="fu">mkin</span><span class="fu">::</span><span class="fu"><a href="../../reference/saem.html">saem</a></span><span class="op">(</span><span class="va">f_parent_mkin_tc</span><span class="op">[</span><span class="st">"DFOP"</span>, <span class="op">]</span><span class="op">)</span></span>
<span><span class="va">f_parent_saemix_dfop_tc_defaults</span><span class="op">$</span><span class="va">so</span> <span class="op">&lt;-</span></span>
@@ -378,7 +536,9 @@ DFOP tc more iterations 665.88 663.80</code></pre>
<div class="section level3">
<h3 id="comparison">Comparison<a class="anchor" aria-label="anchor" href="#comparison"></a>
</h3>
-<p>The following table gives the AIC values obtained with both backend packages using the same control parameters (800 iterations burn-in, 300 iterations second phase, 15 chains).</p>
+<p>The following table gives the AIC values obtained with both backend
+packages using the same control parameters (800 iterations burn-in, 300
+iterations second phase, 15 chains).</p>
<div class="sourceCode" id="cb31"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="va">AIC_all</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/base/data.frame.html" class="external-link">data.frame</a></span><span class="op">(</span></span>
<span> check.names <span class="op">=</span> <span class="cn">FALSE</span>,</span>
@@ -390,7 +550,7 @@ DFOP tc more iterations 665.88 663.80</code></pre>
<span> saemix_is <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/lapply.html" class="external-link">sapply</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="va">f_parent_saemix_sfo_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_sfo_tc</span><span class="op">$</span><span class="va">so</span>,</span>
<span> <span class="va">f_parent_saemix_dfop_const</span><span class="op">$</span><span class="va">so</span>, <span class="va">f_parent_saemix_dfop_tc</span><span class="op">$</span><span class="va">so</span><span class="op">)</span>, <span class="va">AIC</span>, method <span class="op">=</span> <span class="st">"is"</span><span class="op">)</span></span>
<span><span class="op">)</span></span>
-<span><span class="fu">kable</span><span class="op">(</span><span class="va">AIC_all</span><span class="op">)</span></span></code></pre></div>
+<span><span class="fu"><a href="https://rdrr.io/pkg/knitr/man/kable.html" class="external-link">kable</a></span><span class="op">(</span><span class="va">AIC_all</span><span class="op">)</span></span></code></pre></div>
<table class="table">
<thead><tr class="header">
<th align="left">Degradation model</th>
@@ -418,7 +578,7 @@ DFOP tc more iterations 665.88 663.80</code></pre>
<td align="left">DFOP</td>
<td align="left">const</td>
<td align="right">NA</td>
-<td align="right">671.98</td>
+<td align="right">709.26</td>
<td align="right">705.75</td>
</tr>
<tr class="even">
@@ -435,21 +595,33 @@ DFOP tc more iterations 665.88 663.80</code></pre>
<div class="section level2">
<h2 id="conclusion">Conclusion<a class="anchor" aria-label="anchor" href="#conclusion"></a>
</h2>
-<p>A more detailed analysis of the dimethenamid dataset confirmed that the DFOP model provides the most appropriate description of the decline of the parent compound in these data. On the other hand, closer inspection of the results revealed that the variability of the k2 parameter across the population of soils is ill-defined. This coincides with the observation that this parameter cannot robustly be quantified for some of the soils.</p>
-<p>Regarding the regulatory use of these data, it is claimed that an improved characterisation of the mean parameter values across the population is obtained using the nonlinear mixed-effects models presented here. However, attempts to quantify the variability of the slower rate constant of the biphasic decline of dimethenamid indicate that the data are not sufficient to characterise this variability to a satisfactory precision.</p>
+<p>A more detailed analysis of the dimethenamid dataset confirmed that
+the DFOP model provides the most appropriate description of the decline
+of the parent compound in these data. On the other hand, closer
+inspection of the results revealed that the variability of the k2
+parameter across the population of soils is ill-defined. This coincides
+with the observation that this parameter cannot robustly be quantified
+for some of the soils.</p>
+<p>Regarding the regulatory use of these data, it is claimed that an
+improved characterisation of the mean parameter values across the
+population is obtained using the nonlinear mixed-effects models
+presented here. However, attempts to quantify the variability of the
+slower rate constant of the biphasic decline of dimethenamid indicate
+that the data are not sufficient to characterise this variability to a
+satisfactory precision.</p>
</div>
<div class="section level2">
<h2 id="session-info">Session Info<a class="anchor" aria-label="anchor" href="#session-info"></a>
</h2>
<div class="sourceCode" id="cb32"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span><span class="fu"><a href="https://rdrr.io/r/utils/sessionInfo.html" class="external-link">sessionInfo</a></span><span class="op">(</span><span class="op">)</span></span></code></pre></div>
-<pre><code>R version 4.2.2 (2022-10-31)
+<pre><code>R version 4.2.3 (2023-03-15)
Platform: x86_64-pc-linux-gnu (64-bit)
-Running under: Debian GNU/Linux 11 (bullseye)
+Running under: Debian GNU/Linux 12 (bookworm)
Matrix products: default
BLAS: /usr/lib/x86_64-linux-gnu/openblas-serial/libblas.so.3
-LAPACK: /usr/lib/x86_64-linux-gnu/openblas-serial/libopenblas-r0.3.13.so
+LAPACK: /usr/lib/x86_64-linux-gnu/openblas-serial/libopenblas-r0.3.21.so
locale:
[1] LC_CTYPE=de_DE.UTF-8 LC_NUMERIC=C
@@ -463,38 +635,44 @@ attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
-[1] saemix_3.2 npde_3.2 nlme_3.1-160 mkin_1.2.2 knitr_1.41
+[1] saemix_3.2 npde_3.3 nlme_3.1-162 mkin_1.2.3 knitr_1.42
loaded via a namespace (and not attached):
- [1] deSolve_1.34 zoo_1.8-11 tidyselect_1.2.0 xfun_0.35
- [5] bslib_0.4.1 purrr_0.3.5 lattice_0.20-45 colorspace_2.0-3
- [9] vctrs_0.5.1 generics_0.1.3 htmltools_0.5.3 yaml_2.3.6
-[13] utf8_1.2.2 rlang_1.0.6 pkgdown_2.0.6 jquerylib_0.1.4
-[17] pillar_1.8.1 glue_1.6.2 DBI_1.1.3 lifecycle_1.0.3
-[21] stringr_1.4.1 munsell_0.5.0 gtable_0.3.1 ragg_1.2.4
-[25] codetools_0.2-18 memoise_2.0.1 evaluate_0.18 fastmap_1.1.0
-[29] lmtest_0.9-40 parallel_4.2.2 fansi_1.0.3 highr_0.9
-[33] scales_1.2.1 cachem_1.0.6 desc_1.4.2 jsonlite_1.8.3
-[37] systemfonts_1.0.4 fs_1.5.2 textshaping_0.3.6 gridExtra_2.3
-[41] ggplot2_3.4.0 digest_0.6.30 stringi_1.7.8 dplyr_1.0.10
-[45] grid_4.2.2 rprojroot_2.0.3 cli_3.4.1 tools_4.2.2
-[49] magrittr_2.0.3 sass_0.4.3 tibble_3.1.8 pkgconfig_2.0.3
-[53] assertthat_0.2.1 rmarkdown_2.18 R6_2.5.1 mclust_6.0.0
-[57] compiler_4.2.2 </code></pre>
+ [1] highr_0.10 pillar_1.9.0 bslib_0.4.2 compiler_4.2.3
+ [5] jquerylib_0.1.4 tools_4.2.3 mclust_6.0.0 digest_0.6.31
+ [9] tibble_3.2.1 jsonlite_1.8.4 evaluate_0.20 memoise_2.0.1
+[13] lifecycle_1.0.3 gtable_0.3.3 lattice_0.21-8 pkgconfig_2.0.3
+[17] rlang_1.1.0 DBI_1.1.3 cli_3.6.1 yaml_2.3.7
+[21] parallel_4.2.3 pkgdown_2.0.7 xfun_0.38 fastmap_1.1.1
+[25] gridExtra_2.3 dplyr_1.1.1 stringr_1.5.0 generics_0.1.3
+[29] desc_1.4.2 fs_1.6.1 vctrs_0.6.1 sass_0.4.5
+[33] systemfonts_1.0.4 tidyselect_1.2.0 rprojroot_2.0.3 lmtest_0.9-40
+[37] grid_4.2.3 glue_1.6.2 R6_2.5.1 textshaping_0.3.6
+[41] fansi_1.0.4 rmarkdown_2.21 purrr_1.0.1 ggplot2_3.4.2
+[45] magrittr_2.0.3 codetools_0.2-19 scales_1.2.1 htmltools_0.5.5
+[49] colorspace_2.1-0 ragg_1.2.5 utf8_1.2.3 stringi_1.7.12
+[53] munsell_0.5.0 cachem_1.0.7 zoo_1.8-12 </code></pre>
</div>
<div class="section level2">
<h2 id="references">References<a class="anchor" aria-label="anchor" href="#references"></a>
</h2>
<!-- vim: set foldmethod=syntax: -->
-<div id="refs" class="references hanging-indent">
-<div id="ref-efsa_2018_dimethenamid">
-<p>EFSA. 2018. “Peer Review of the Pesticide Risk Assessment of the Active Substance Dimethenamid-P.” <em>EFSA Journal</em> 16 (4): 5211.</p>
+<div id="refs" class="references csl-bib-body hanging-indent">
+<div id="ref-efsa_2018_dimethenamid" class="csl-entry">
+EFSA. 2018. <span>“Peer Review of the Pesticide Risk Assessment of the
+Active Substance Dimethenamid-p.”</span> <em>EFSA Journal</em> 16: 5211.
</div>
-<div id="ref-ranke2021">
-<p>Ranke, Johannes, Janina Wöltjen, Jana Schmidt, and Emmanuelle Comets. 2021. “Taking Kinetic Evaluations of Degradation Data to the Next Level with Nonlinear Mixed-Effects Models.” <em>Environments</em> 8 (8). <a href="https://doi.org/10.3390/environments8080071" class="external-link">https://doi.org/10.3390/environments8080071</a>.</p>
+<div id="ref-ranke2021" class="csl-entry">
+Ranke, Johannes, Janina Wöltjen, Jana Schmidt, and Emmanuelle Comets.
+2021. <span>“Taking Kinetic Evaluations of Degradation Data to the Next
+Level with Nonlinear Mixed-Effects Models.”</span> <em>Environments</em>
+8 (8). <a href="https://doi.org/10.3390/environments8080071" class="external-link">https://doi.org/10.3390/environments8080071</a>.
</div>
-<div id="ref-dimethenamid_rar_2018_b8">
-<p>Rapporteur Member State Germany, Co-Rapporteur Member State Bulgaria. 2018. “Renewal Assessment Report Dimethenamid-P Volume 3 - B.8 Environmental fate and behaviour, Rev. 2 - November 2017.” <a href="https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>.</p>
+<div id="ref-dimethenamid_rar_2018_b8" class="csl-entry">
+Rapporteur Member State Germany, Co-Rapporteur Member State Bulgaria.
+2018. <span>“<span class="nocase">Renewal Assessment Report
+Dimethenamid-P Volume 3 - B.8 Environmental fate and behaviour, Rev. 2 -
+November 2017</span>.”</span> <a href="https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716" class="external-link">https://open.efsa.europa.eu/study-inventory/EFSA-Q-2014-00716</a>.
</div>
</div>
</div>
@@ -517,7 +695,7 @@ loaded via a namespace (and not attached):
<div class="pkgdown">
<p></p>
-<p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.6.</p>
+<p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.7.</p>
</div>
</footer>

Contact - Imprint