Displaying 5 results from an estimated 5 matches for "survconcordance".
2011 Jul 08
1
survConcordance with 'counting' type Surv()
Dear Prof. Therneau
I was impressed to discover that the 'survConcordance' now handles Surv() objects in counting format (example below to clarify what I mean). This is not documented in the help page for the function. I am very curious to see how a c-index is estimated in this case, using just the linear predictors. It was my impression that with left truncation the...
2012 Jun 25
2
Fast Kendall's Tau
Hello.
Has any further action been taken regarding implementing David Simcha's fast Kendall tau code (now found in the package pcaPP as cor.fk) into R-base? It is literally hundreds of times faster, although I am uncertain as to whether he wrote code for testing the significance of the parameter. The last mention I have seen of this was in 2010
2011 Jun 24
1
UnoC function in survAUC for censoring-adjusted C-index
...eft NULL, the maximum futime in the TE data is assumed:
UnoC(Surv.rsp, Surv.rsp.new, lpnew, time=NULL)
#same as
UnoC(Surv.rsp, Surv.rsp.new, lpnew, time=max(Surv.rsp.new[,1]))
#which incidentally is the same as what one gets with the usual C-index function that also extends to the max event time.
survConcordance(Surv.rsp.new ~ lpnew)$conc
Now, if I specify a range times 'tau' (as in Table III of the relevant publication) I still get the same C for each timepoint:
tau <- Surv.rsp.new[, 1]
> tau
[1] 1040 1106 1129 1206 1227 268 329 353 365 377
UnoC(Surv.rsp, Surv.rsp.new, lpnew, time=...
2013 Jul 11
0
[R-pkgs] Major Update to rms package
...Use options(showevery=50) to update the progress bar only every
50 iterations.
* Made all design matrices stored in model fits exclude any
intercepts, with columns of ones added as needed with Predict() etc.
* Dxy and c-index are now calculated with Therneau''s survival
package survConcordance functions which is blazing fast so can be used
routinely in all model validations that used Dxy
* plot.summary.rms now produces cleaner output with fewer confidence
levels
* Several bug corrections
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Changes in version...
2010 Apr 08
2
C-index and Cox model
Dear all R users,
I am building a Cox PH model on a small dataset. I am wondering how to
measure the predictive power of my cox model? Normally the ROC curve or Gini
value are used in logistic regression model. Is there any similar
measurement suitable for Cox model?
Also if I use C-index statistic to measure the predictive power, is it a
time-dependent value (i.e. do I need to calculate it for