<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Hi Alexandre,</div><div><br><blockquote type="cite"><div>First, I am not sure how BIOMOD calculates the optimized ROC<br>threshold. In the manual I found:"Optimized Threshold (...) It<br>represents the best probability threshold<br>maximizing the percentage of presence and absence correctly predicted<br>for the evaluation data.". Does it mean maximizing the SUM of<br>sensitivity and specificity?<br></div></blockquote><div><br></div><div>It means minimizing the difference between sp and se (when the curves crossed). </div><br><blockquote type="cite"><div>Second, how can I calculate the final accuracy for a binary ensemble<br>forecast model?<br></div></blockquote><div><br></div><div>If the Ensemble Forecast has been carried out on the same points than the initial models, just type: Test=T in the Ensemble.Forecasting function:</div><div><br></div><div><span class="Apple-style-span" style="font-family: Times; "><pre>Ensemble.Forecasting(Proj.name= "Future1", weight.method='Roc', PCA.median=TRUE, binary=TRUE, bin.method='Roc', Test=TRUE, repetition.models=TRUE)</pre></span><div>Else you can use the inner function in BIOMOD or in R:</div><div><br></div><div>somers2(Fit, Obs) will give you the AUC. </div><div><br></div><div>or to have the Kappa or TSS</div><div><br></div><div>KappaRepet(Obs, Fit, TSS = TRUE)</div><div><br></div></div><div>Hope it helps,</div><div>Wilfried</div><div><br></div><div><br></div><br><blockquote type="cite"><div><br>Thanks a lot for the help!<br><br>Alexandre<br>_______________________________________________<br>Biomod-commits mailing list<br><a href="mailto:Biomod-commits@lists.r-forge.r-project.org">Biomod-commits@lists.r-forge.r-project.org</a><br>https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/biomod-commits<br></div></blockquote></div><br><div>
<div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><span class="Apple-style-span" style="font-size: 12px; "><div>--------------------------</div><div>Dr. Wilfried Thuiller</div><div>Laboratoire d'Ecologie Alpine, UMR CNRS 5553</div><div>Université Joseph Fourier</div><div>BP53, 38041 Grenoble cedex 9, France</div><div>tel: +33 (0)4 76 63 54 53</div><div>fax: +33 (0)4 76 51 42 79</div><div><br></div><div>Email: <a href="mailto:wilfried.thuiller@ujf-grenoble.fr">wilfried.thuiller@ujf-grenoble.fr</a><br>Home page: <a href="http://www.will.chez-alice.fr/">http://www.will.chez-alice.fr</a><br>Website: <a href="http://www-leca.ujf-grenoble.fr/equipes/tde.htm">http://www-leca.ujf-grenoble.fr/equipes/tde.htm</a><br><br>FP6 European MACIS project: <a href="http://www.macis-project.net/">http://www.macis-project.net</a><br>FP6 European EcoChange project: <a href="http://www.ecochange-project.eu/">http://www.ecochange-project.eu</a></div><div><br></div></span></div></div><br class="Apple-interchange-newline"><br class="Apple-interchange-newline">
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