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</div> <div id="ref-usage"> <div class="sourceCode"><pre class="sourceCode r"><code><span class="co"># S3 method for mmkin</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">object</span>, <span class="va">...</span>, k <span class="op">=</span> <span class="fl">2</span><span class="op">)</span> <span class="co"># S3 method for mmkin</span> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">BIC</a></span><span class="op">(</span><span class="va">object</span>, <span class="va">...</span><span class="op">)</span></code></pre></div> </div> <div id="arguments"> <h2>Arguments</h2> <dl><dt>object</dt> <dd><p>An object of class <code><a href="mmkin.html">mmkin</a></code>, containing only one column.</p></dd> <dt>...</dt> <dd><p>For compatibility with the generic method</p></dd> <dt>k</dt> <dd><p>As in the generic method</p></dd> </dl></div> <div id="value"> <h2>Value</h2> <p>As in the generic method (a numeric value for single fits, or a dataframe if there are several fits in the column).</p> </div> <div id="author"> <h2>Author</h2> <p>Johannes Ranke</p> </div> <div id="ref-examples"> <h2>Examples</h2> <div class="sourceCode"><pre class="sourceCode r"><code><span class="r-in"></span> <span class="r-in"> <span class="co"># skip, as it takes > 10 s on winbuilder</span></span> <span class="r-in"> <span class="va">f</span> <span class="op"><-</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/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"SFO"</span>, <span class="st">"FOMC"</span>, <span class="st">"DFOP"</span><span class="op">)</span>,</span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="st">"FOCUS A"</span> <span class="op">=</span> <span class="va">FOCUS_2006_A</span>,</span> <span class="r-in"> <span class="st">"FOCUS C"</span> <span class="op">=</span> <span class="va">FOCUS_2006_C</span><span class="op">)</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> <span class="r-wrn co"><span class="r-pr">#></span> <span class="warning">Warning: </span>Optimisation did not converge:</span> <span class="r-wrn co"><span class="r-pr">#></span> false convergence (8)</span> <span class="r-in"> <span class="co"># We get a warning because the FOMC model does not converge for the</span></span> <span class="r-in"> <span class="co"># FOCUS A dataset, as it is well described by SFO</span></span> <span class="r-in"></span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span><span class="st">"SFO"</span>, <span class="st">"FOCUS A"</span><span class="op">]</span><span class="op">)</span> <span class="co"># We get a single number for a single fit</span></span> <span class="r-out co"><span class="r-pr">#></span> [1] 55.28197</span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[[</span><span class="st">"SFO"</span>, <span class="st">"FOCUS A"</span><span class="op">]</span><span class="op">]</span><span class="op">)</span> <span class="co"># or when extracting an mkinfit object</span></span> <span class="r-out co"><span class="r-pr">#></span> [1] 55.28197</span> <span class="r-in"></span> <span class="r-in"> <span class="co"># For FOCUS A, the models fit almost equally well, so the higher the number</span></span> <span class="r-in"> <span class="co"># of parameters, the higher (worse) the AIC</span></span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span>, <span class="st">"FOCUS A"</span><span class="op">]</span><span class="op">)</span></span> <span class="r-out co"><span class="r-pr">#></span> df AIC</span> <span class="r-out co"><span class="r-pr">#></span> SFO 3 55.28197</span> <span class="r-out co"><span class="r-pr">#></span> FOMC 4 57.28198</span> <span class="r-out co"><span class="r-pr">#></span> DFOP 5 59.28197</span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span>, <span class="st">"FOCUS A"</span><span class="op">]</span>, k <span class="op">=</span> <span class="fl">0</span><span class="op">)</span> <span class="co"># If we do not penalize additional parameters, we get nearly the same</span></span> <span class="r-out co"><span class="r-pr">#></span> df AIC</span> <span class="r-out co"><span class="r-pr">#></span> SFO 3 49.28197</span> <span class="r-out co"><span class="r-pr">#></span> FOMC 4 49.28198</span> <span class="r-out co"><span class="r-pr">#></span> DFOP 5 49.28197</span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">BIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span>, <span class="st">"FOCUS A"</span><span class="op">]</span><span class="op">)</span> <span class="co"># Comparing the BIC gives a very similar picture</span></span> <span class="r-out co"><span class="r-pr">#></span> df BIC</span> <span class="r-out co"><span class="r-pr">#></span> SFO 3 55.52030</span> <span class="r-out co"><span class="r-pr">#></span> FOMC 4 57.59975</span> <span class="r-out co"><span class="r-pr">#></span> DFOP 5 59.67918</span> <span class="r-in"></span> <span class="r-in"> <span class="co"># For FOCUS C, the more complex models fit better</span></span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">AIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span>, <span class="st">"FOCUS C"</span><span class="op">]</span><span class="op">)</span></span> <span class="r-out co"><span class="r-pr">#></span> df AIC</span> <span class="r-out co"><span class="r-pr">#></span> SFO 3 59.29336</span> <span class="r-out co"><span class="r-pr">#></span> FOMC 4 44.68652</span> <span class="r-out co"><span class="r-pr">#></span> DFOP 5 29.02372</span> <span class="r-in"> <span class="fu"><a href="https://rdrr.io/r/stats/AIC.html" class="external-link">BIC</a></span><span class="op">(</span><span class="va">f</span><span class="op">[</span>, <span class="st">"FOCUS C"</span><span class="op">]</span><span class="op">)</span></span> <span class="r-out co"><span class="r-pr">#></span> df BIC</span> <span class="r-out co"><span class="r-pr">#></span> SFO 3 59.88504</span> <span class="r-out co"><span class="r-pr">#></span> FOMC 4 45.47542</span> <span class="r-out co"><span class="r-pr">#></span> DFOP 5 30.00984</span> <span class="r-in"> </span> <span class="r-in"></span> </code></pre></div> </div> </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></p><p>Developed by Johannes Ranke.</p> </div> <div class="pkgdown"> <p></p><p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.3.</p> </div> </footer></div> </body></html>