search for: tfit

Hi all, I am trying to fit t distribution using the function "tFit" in the library(fBasics). I am using the code tFit(datac[[2]]) and it returns the following list. Title: Student-t Parameter Estimation Call: tFit(x = datac[[2]]) Model: Student-t Distribution Estimated Parameter(s): df 78.4428 I just wonder how can I refer to the estimated p...

Dear R-user: I am using survreg(Surv()) for fitting a Tobit model of left-censored longitudinal data. For logarithmic transformation of y data, I am trying use survreg.distributions in the following way: tfit=survreg(Surv(y, y>=-5, type="left")~x + cluster(id), dist="gaussian", data=y.data, scale=0, weights=w) my.gaussian<-survreg.distributions$gaussian my.gaussian$name="lognormal" my.gaussian$dist<-my.gaussian tfit=survreg(Surv(y, y>=-5, type="left")...

...nd left-truncated it at the same spot, so that I am able to make 2 estimations (one for censoring and one for truncation). I know how to make the linear regression for the left-censored variable (hours) and how to plot the regression line into the (x,y) plot (packages AER, Zeileis, Survival, ...): tfit<-survreg(Surv(Hours,Hours>0, type='left')~Yrs_Ed,data=DataWomen,dist='gaussian') z<-predict(tfit,type="response") plot(Yrs_Ed,Hours) abline(tfit) My aim is to compare the effects of truncation and censoring graphically by plotting the two regression lines into on...

...x1, x2) > head(D) y x1 x2 1 0.0000000 0.86848630 2.6275703 2 0.0000000 0.88675832 1.7199261 3 2.7559349 0.38341782 0.6247869 4 0.0000000 0.02679007 2.4617981 5 2.2634588 0.96974450 0.4345950 6 0.6563741 0.92623096 2.4983289 > # Estimate it > library(survival) > tfit <- survreg(Surv(y, y>0, type='left') ~ x1 + x2, data=D, dist='gaussian', link='identity') It says: Error in survreg.control(...) : unused argument(s) (link ...) Execution halted My competence on library(survival) is zero. Is it still the case t...

Calum had a long question about drawing survival curves after fitting a Weibull model, using pweibull, which I have not reproduced. It is easier to get survival curves using the predict function. Here is a simple example: > library(survival) > tfit <- survreg(Surv(time, status) ~ factor(ph.ecog), data=lung) > table(lung$ph.ecog) 0 1 2 3 <NA> 63 113 50 1 1 > tdata <- data.frame(ph.ecog=factor(0:3)) > qpred <- predict(tfit, newdata= tdata, type='quantile', p=1:99/100) > matplot(t(qpre...

Hi All, I am running a scatter plot and trying to add a best fit line. I use an abline function, but get no line drawn over the points. I also get no error. I arm using V 2.10.0 on Windows 7. Here is my code, including the SAS transport file import: require (foreign) require (chron) require (Hmisc) require (lattice) clin <- sasxport.get("y:\\temp\\subset.xpt") attach(clin)

...om umn.edu makes me wonder if there's homework involved.... Simpler for your example is to use get and subset. dat <- structure(..... as found below var.to.test <- names(dat)[4:6] #variables of interest nvar <- length(var.to.test) chisq <- double(nvar) for (i in 1:nvar) { tfit <- survdiff(Surv(time, completion==2) ~ get(var.to.test[i]), data=dat, subset=(group==3)) chisq[i] <- tfit$chisq } write.csv(data.frame(var.to.test, chisq)) On 10/19/2012 05:00 AM, r-help-request at r-project.org wrote: > Hello, > > I am trying to set up a loop that can r...

...K * checking for portable use of $BLAS_LIBS ... OK * creating survival-Ex.R ... OK * checking examples ... OK * checking tests ... make[1]: Entering directory `/home/therneau/research/surv/Rforge/pkg/survival.Rcheck/tests' Running 'aareg.R' make[1]: *** [aareg.Rout] Error 1 ... > tfit <- aareg(Surv(time, status) ~ x, test1) Error: could not find function "aareg" Execution halted -------------- The manual page aareg.Rd has a call to the function in the examples and that runs ok, and aareg is in the NAMESPACE exports. I'm almost certainly missing somethi...

Hello, I am running R 2.6.1 on windows xp I am trying to fit a cox proportional hazard model with a shared Gaussian frailty term using coxme My model is specified as: nofit1<-coxme(Surv(Age,cen1new)~ Sex+bo2+bo3,random=~1|isl,data=mydat) With x1-x3 being dummy variables, and isl being the community level variable with 4 levels. Does anyone know if there is a way to get the standard error

Hi, I'm going crazy trying to plot a quite simple graph. i need to plot estimated hazard rate from a cox model. supposing the model i like this: coxPhMod=coxph(Surv(TIME, EV) ~ AGE+A+B+strata(C) data=data) with 4 level for C. how can i obtain a graph with 4 estimated (better smoothed) hazard curve (base-line hazard + 3 proportional) to highlight the effect of C. thanks!! laudan [[alternative

Hi, I am using rpart as a part of my masters' project. I am trying to print out the resulting model using plot() function along with text() function. I am having difficulties with labels being cut-off. In text() function, I am using use.n=T option to get the number of people in each nodes but the on the lower and left part of the plot, the numbers get cut off. Thanks! Linus [[alternative

-- begin included message -- Hi, but why we do the difference : ltemp <- 2 * diff(tfit $loglik[1:2]) ?? Where I can find information about Integrate Likelihooh and null like lihood?? --- end inclusion --- 1. Basic statistical fact: 2 * difference in loglik between two nested models = distributed as a chi-square distribution. For coxme loglik[1] = likelihood from a null model (a...