similar to: ROC

Displaying 20 results from an estimated 10000 matches similar to: "ROC"

2009 Nov 04
0
Fw: ROC
if nobody knows the answer to my question on time-dependent ROC (see below), does any body know how TP and FP are related to classes and samples (orders) in non-time dependent ROC? Any reference? Thanks --- On Tue, 11/3/09, carol white <wht_crl at yahoo.com> wrote: > From: carol white <wht_crl at yahoo.com> > Subject: ROC > To: r-help at stat.math.ethz.ch > Date:
2010 Dec 05
1
HOW to use the survivalROC to get optimal cut-off values?
I have the same problem of a prevous request HOW to use the survivalROC (or another library in R) to get optimal cut-off values? I want to use the time-dependent survivalROC package.according to the,reference material,it only gives a set of ordered cut-off values .eg. -------------------------------------------------------------------------------- data(mayo) str(mayo) attach(mayo)
2010 Dec 05
1
HOW to use str() after the survivalROC (or another library in R) to get optimal cut-off values
I have the same problem of a previous request HOW to use the survivalROC (or another library in R) to get optimal cut-off values? I want to use the time-dependent survivalROC package.according to the,reference material,it only gives a partial set of ordered cut-off values .eg. -------------------------------------------------------------------------------- data(mayo) str(mayo) attach(mayo)
2014 Jun 23
2
Resumen de R-help-es, Vol 64, Envío 33
Hola, Marta, Por lo que he podido ver tus datos ya tienen calculados las tasas de verdaderos y falsos positivos (TPR y FPR). También parece que los tienes ordenados por la variable FishSpeed y supongo que también por las que parecen marcas de tiempo. No necesitas ROCR porque con un simple plot te sale algo parecido a una curva. Eso sí, veo que son medidas repetidas en el tiempo para cada valor de
2014 Jun 20
2
Como construir una curva ROC
Hola! Tengo que hacer una curva ROC com unos datos que obtuve de hacer una macro de excel y aplicar unas reglas, y basicamente tengo que a partir de la variacion del tiempo y la velocidad del barco obtengo diferentes porcentajes de true positives (TP) y false positives (FP) y con eso deberia de construir una curva ROC. Dada mi ignorância en este tema, no se muy bien por donde empezar , estuve
2008 Jul 17
1
Comparing differences in AUC from 2 different models
Hi, I would like to compare differences in AUC from 2 different models, glm and gam for predicting presence / absence. I know that in theory the model with a higher AUC is better, but what I am interested in is if statistically the increase in AUC from the glm model to the gam model is significant. I also read quite extensive discussions on the list about ROC and AUC but I still didn't find
2009 Jul 15
1
negative Somers D from Design package
Dear R help My problem is very similar to the analysis detailed here. If we use the mayo dataset provided with the survivalROC package the estimate for Somer's Dxy is very negative -0.56. The Nagelkerke R2 is positive though 0.32. I know there is a difference between explained variation and predictive ability but I am surprised there is usch a difference given that even a non predictive model
2010 Aug 17
1
ROCR predictions
Hi everybody, I am having a problem building a ROC curve with my data using the ROCR package. I have 10 lists of proteins such as attached (proteinlist.xls). each of the lists was calculated with a different p-value. The goal is to find the optimal p-value for the highest number of true positives as well as lowaest number of false positives. As far as I understood the explanations from the
2006 Mar 15
1
How to compare areas under ROC curves calculated with ROCR package
Dear all, I try to compare the performances of several parameters to diagnose lameness in dogs. I have several ROC curves from the same dataset. I plotted the ROC curves and calculated AUC with the ROCR package. I would like to compare the AUC. I used the following program I found on R-help archives : From: Bernardo Rangel Tura Date: Thu 16 Dec 2004 - 07:30:37 EST
2009 Nov 21
2
Fw: Re: title problem
It seems that there is a problem in displaying subtitle in general, independently from multi-plot display. when I do plot (c(1,2,3), c(9,8,7), type = "l") title(main = "Main title", sub ="Sub title",cex.main=2, cex.sub = 2) subtitle doesn't get displayed > --- On Sat, 11/21/09, David Winsemius <dwinsemius at comcast.net> > wrote: >
2011 Apr 27
2
ROCR for combination of markers
Dear list   I have 5 markers that can be used to detect an infection in combination. Could you please advise me how to use functions in ROCR/ other package to produce the ROC curve for a combination of markers?   I have used the following to get ROC statistics for each marker. pred <- prediction(y$marker1, y$infectn) perf <-performance(pred,"tpr","fpr")
2005 Sep 22
2
Survey of ROC AUC / wilcoxon test functions
Hi, I was lately debugging parts of my 'colAUC' function in caTools package, and in a process looked into other packages for calculating Areas Under ROC Curves (AUC). To my surprise I found at least 6 other functions: * wilcox.test * AUC from ROC package, * performance from ROCR package, * auROC from limma package, * ROC from Epi package, * roc.area from verification
2009 Nov 25
0
ROCR Issue: Averaging Across Multiple Classifier Runs in ROC Curve
Dear R-philes, I am having some trouble averaging across multiple runs of a classifier in an ROC Curve. I am using the ROCR package and the plot() method. First, I initialize a list with two elements where each element is a list of predictions and labels: vowel.ROC <- list(predictions=list(), labels=list()) For every run of the classifier, I append the scores and labels to their
2011 Jul 11
1
Named numeric vectors with the same value but different names return different results when used as thresholds for calculating true positives
Dear List, I have encountered an odd problem that I cannot understand. It stems from the calculation of true and false positives based on two input vectors x and y based on different thresholds of x, extracted using the quantile function. I am in certain cases getting different values of true positives for the same threshold value when the threshold was found under different quantiles (e.g. the
2011 Mar 31
0
pROC 1.4.3: compare two ROC curves in R
Dear R users, pROC is a package to compare, visualize, and smooth receiver operating characteristic (ROC) curves. The package provides the following features: * Partial or full area under the curve (AUC) computation * Comparison of two ROC curves (curves and AUC) * Calculating and plotting confidence intervals * Smoothing of the ROC curve * Coordinates extraction ('coords' function).
2011 Mar 31
0
pROC 1.4.3: compare two ROC curves in R
Dear R users, pROC is a package to compare, visualize, and smooth receiver operating characteristic (ROC) curves. The package provides the following features: * Partial or full area under the curve (AUC) computation * Comparison of two ROC curves (curves and AUC) * Calculating and plotting confidence intervals * Smoothing of the ROC curve * Coordinates extraction ('coords' function).
2006 Mar 20
1
How to compare areas under ROC curves calculated with ROC R package
I might be missing something but I thought that AUC was a measure for comparing ROC curves, so there is nothing else needed to "compare" them. The larger AUC is the higher correlation of 2 variables compared. No other measures or calculations are needed. Jarek Tuszynski -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On
2011 Mar 28
0
How can I plot several ROC curves on the same graph?
Hello I am trying to make a graph of 10 different lines built each from 4 different segments and to add a darker line that will represent the average of all graphs - all in the same plot.Actually each line is a ROC plot The code I'm using for plotting one line is as follows: logit.roc.plot <- function(r, title="ROC curve") { old.par <- par(no.readonly = TRUE);
2011 Mar 29
1
plotting several ROC curves on the same graph
Hello I am trying to make a graph of 10 different lines built each from 4 different segments and to add a darker line that will represent the average of all graphs - all in the same plot.Actually each line is a ROC plot The code I'm using for plotting one line is as follows: logit.roc.plot <- function(r, title="ROC curve") { old.par <- par(no.readonly = TRUE);
2005 Dec 15
3
Name conflict between Epi and ROC packages
The name conflicts in Epi and ROC packages (2 'ROC' functions are the problem) cause the following code to work once, but not twice: library(MASS); data(cats); x = cats[,2] y = ifelse(cats[,1]=='F',0,1) library(Epi); ROC(x,y,grid=0)$AUC library(ROC); AUC(rocdemo.sca(y, x, dxrule.sca)) What is the standard way of resolving name conflicts? Ask maintainers to resolve