ROCR: Visualizing classifier performance in R

Department of Computational Biology and Applied Algorithmics, Max-Planck-Institute for Informatics, Saarbrücken, Germany.
Bioinformatics (Impact Factor: 4.62). 11/2005; 21(20):3940-1. DOI: 10.1093/bioinformatics/bti623
Source: PubMed

ABSTRACT ROCR is a package for evaluating and visualizing the performance of scoring classifiers in the statistical language R. It
features over 25 performance measures that can be freely combined to create two-dimensional performance curves. Standard methods
for investigating trade-offs between specific performance measures are available within a uniform framework, including receiver
operating characteristic (ROC) graphs, precision/recall plots, lift charts and cost curves. ROCR integrates tightly with R's
powerful graphics capabilities, thus allowing for highly adjustable plots. Being equipped with only three commands and reasonable
default values for optional parameters, ROCR combines flexibility with ease of usage.

Availability: ROCR can be used under the terms of the GNU General Public License. Running within R, it is platform-independent.

Contact: tobias.sing{at}

    • "ances of the investigated classifier ( Fawcett , 2004 ) . The Area Under the ROC curve ( AUC ) was also calculated , to consider in a single scalar value the ability of the classifier to differentiate between the distributions of the two classes ( Hand and Till , 2001 ) . ROC analysis was conducted using ROCR toolkit for the R computing language ( Sing et al . , 2005 ) ."
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    Toxicology in Vitro 07/2015; DOI:10.1016/j.tiv.2015.07.013 · 3.21 Impact Factor
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    • "Model adequacy was evaluated by plotting residuals versus fitted values and explanatory variables. Model fit was evaluated by the adjusted r 2 and by using the Area Under the Curve (AUC) generated by the Receiver Operating Characteristic (ROC; Pearce and Ferrier 2000), estimated using the ROCR package (Sing et al. 2005). A GAM between time of day and temperature showed an obvious association between both variables (adjusted R 2 of 0.40 for breeding, 0.33 for post breeding, and 0.68 for winter), at least for specific daylight time periods, which hindered the estimation of the net temperature effect. "
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    Ecosphere 07/2015; 6(7). DOI:10.1890/ES14-00454.1 · 2.60 Impact Factor
    • "Two components of the model's predictive performance were assessed in the evaluation dataset, namely discrimination and reliability (Jim enez-Valverde et al., 2013). The area under the curve of the receiver operating characteristic plot (AUC) was computed using the R package 'ROCR' (Sing et al., 2005) to assess the discriminatory power of the model in the evaluation data. The reliability of the predicted probabilities was estimated by exploring the calibration plots (Pearce & Ferrier, 2000). "
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    ABSTRACT: AimA striking case of mitochondrial DNA (mtDNA) introgression occurs in the Iberian Peninsula: the mtDNA of Lepus timidus, a species that inhabited this territory during the Last Glacial Maximum (LGM), is almost fixed in the Iberian range of Lepus europaeus, is very frequent in the northern half of Iberia within Lepus granatensis, and is fixed in Lepus castroviejoi. Here, we used a transdisciplinary approach to understand the ecological drivers of the distribution of this introgressed mtDNA in the Iberian hare species.LocationEurope, with an emphasis on the Iberian Peninsula.Methods First, we modelled the climatic niche of L. timidus to predict the favourability for the species during the LGM. Second, we gathered data regarding L. timidus mtDNA introgression for 1137 individuals (139 populations) from the Iberian Peninsula. We tested whether the climatic favourability for L. timidus during the LGM reflects the frequency of the introgressed mtDNA in the carrier hare populations.ResultsThe climatic favourability for the LGM is positively related to the presence of individuals with L. timidus mtDNA, and discriminates better than by chance between individuals with and without this lineage. At the population level, the favourability values relate to the observed frequencies of mtDNA introgression and discriminate between populations with and without L. timidus mtDNA.Main conclusionsThe results suggest that the geographical distribution of L. timidus mtDNA introgression is linked to L. timidus distribution in Iberia during the LGM. Our study helps to improve our understanding of the role of climate in the reticulated evolutionary history of hares, and is a first step towards understanding the ecological impact of mtDNA introgression on Iberian hares.
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