similar to: negative Somers D from Design package

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)

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)

Dear All, Is it possible to get confidence intervals for Harrell's concordance index or, equivalently, Somer's D using the rms package or in some other way ? I have survival data it would be the c-index in the Cox model setting Many thanks Dr Bernard North Statistical Consultant Statistical Advisory Service Advice and Courses on Research Design and Methodology Imperial College South

Dear All, I am trying to calculate a 95% confidence interval for the difference in two c statistics (or equivalently D statistics). In Stata I gather that this can be done using the lincom command. Is there anything similar in R? As you can see below I have two datasets (that are actually two independent subsets of the same data) and the respective c statistics for the variables in both cases.

Does anyone know about functions for calculating Somer's D in R? Perhaps even a version for censored values, like the two functions in hmisc? Thanks for any pointers -- Dr. Jens Oehlschl?gel-Akiyoshi MD FACTORY GmbH Bayerstrasse 21 80335 M?nchen Tel.: 089 545 28-27 Fax.: 089 545 28-10 http://www.mdfactory.de -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-

Hello R Community, I'm continuing to work through logistic regression (thanks for all the help on score test) and have come up against a new opposition. I'm trying to compute Somers Dyx as some suggest this is the preferred method to Somers Dxy (Demaris, 1992). I have searchered the [R] archieves to no avail for a function or code to compute Dyx (not Dxy). The overview of Hmisc has

Dear colleagues in R, Has anybody implemented the 1) (Goodman & Kruskal) lambda or the 2) (Thiel's) uncertainty coefficient statistics (in the asymmetric and symmetric forms), or is anyone aware that they might reside in some package? A search in the R archives does indicate that they are (somehow) part of the CoCo package, but I would rather not start learning how to transform my

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

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:

My question would be related more to time-dependent ROC (survivalROC package): I would like to know how true positives (TP) and false positives (FP) are related to the order of survival times and diagnostic markers. That is, having the a set of TP and FP, each of them is calculated from which diagnostic marker and survival times. Let's take mayo data set. How could I match the TP and FP

Dear R help, I am having a problem with the Design package and my problem is detailed here. I fit a cox model to my data and validate the Somer's Dxy using the Design package. (Because of computation time problem, i only try 10 bootstrap samples for the time being) This is the model without stratification: > library(Design) >

Alt-binz 0.28.5 used to run fine under Wine. It have recently started using significantly more memory and since 1.2-rc1 it gives an error when starting up. I'm currently running a regression test for the error. The memory is harder to test, since it grows slowly. (Any other factors that can cause it? I'm now running Compiz an) Log for when it gives error: (Launched with alias that

(quoting from the web archive, I only just subscribed) Monty wrote: > > > (a bit testy that this flamewar has started again, and no one has learned a > > thing from the previous rounds) > > OK, that wasn't fair... the old timers know what's up, but I do wish some of > the folks who bring things up would browse the archive threads or at least not > jump in