[R] k-folds cross validation with conditional logistic regression

2011-12-10 Thread Ross Crandall
I have a matched-case control dataset that I'm using conditional logistic regression (clogit in survival) to analyze. I'm trying to conduct k-folds cross validation on my top models but all of the packages I can find (CVbinary in DAAG, KVX) won't work with clogit models. Is there any easy way to

Re: [R] profile likelihood

2011-12-10 Thread plocq
Thank you for your response. In fact, it seems not to be adapted to the Poisson model... : library(evd) uvdata - rgpd(100, loc = 0, scale = 1.1, shape = 0.2) M1 - fpot(uvdata, 1, model=pp) library(SpatialExtremes) profile(M1) -- View this message in context:

[R] efficiently finding the integrals of a sequence of functions

2011-12-10 Thread JeffND
Hi folks, I am having a question about efficiently finding the integrals of a list of functions. To be specific, here is a simple example showing my question. Suppose we have a function f defined by f-function(x,y,z) c(x,y^2,z^3) Thus, f is actually corresponding to three uni-dimensional

[R] Correlations for spatio-temporal data ?

2011-12-10 Thread Jian Zhang
I have a dataset like this: sites years Var1 Var2 1 1960 505 3.013833 1 1961 533 4.118784 1 1962 609 14.96386 1 1963 465 -3.74409 1 1964 837 41.70164 1 1965 727 29.53478 2 1960 493 3.269235 2 1961 535 5.386015 2 1962 608

[R] Overlaying density plot on forest plot

2011-12-10 Thread Frank Peter
Dear R User, Please, I am new to R. I want to overlay density plot for predictive interval pooled result in meta-analysis. http://addictedtor.free.fr/graphiques/graphcode.php?graph=114 Regards Frank Peter __ R-help@r-project.org mailing list

Re: [R] installing binary packages across windows cluster

2011-12-10 Thread Prof Brian Ripley
On 10/12/2011 03:54, Benjamin Tyner wrote: Hi Given a cluster of identical windows machines all running the same version of R, are there any circumstances where using install.packages() to install a package (say, one that doesn't have any dependencies) on just a single machine, then copying the

Re: [R] nice report generator?

2011-12-10 Thread Tal Galili
Hello again Duncan, I am sorry it took me two days to get back to your response. Regarding reshape - It is well presented here: http://www.jstatsoft.org/v21/i12 And there is also more information about it here: http://had.co.nz/reshape/ After playing around with it, I wrote a small bridge

[R] Question about comparison of nested models and F-statistics

2011-12-10 Thread олег ---
Hello, I have a linear model with 10 regressors, and summary() gives me F-statistics. After deleting a term with smallest p-value the new model was obtained with F-statistics higher then it was for full model. Does this mean that parsimonius model is better? The distributions of dependent variable

Re: [R] matrix calculation

2011-12-10 Thread R. Michael Weylandt
Perhaps something like this (untested) -- it's going to depend on the exact structure of your data so if this doesn't work, please use dput() to send a plain text representation: tapply(data, data$animal, function(d) d[, c(A01, A02)] - d[d$time == d0, c(A01, A02)] ) In short, take data split it

Re: [R] matrix calculation

2011-12-10 Thread David Winsemius
On Dec 10, 2011, at 9:13 AM, R. Michael Weylandt wrote: Perhaps something like this (untested) -- it's going to depend on the exact structure of your data so if this doesn't work, please use dput() to send a plain text representation: tapply(data, data$animal, function(d) d[, c(A01, A02)] -

Re: [R] Question about comparison of nested models and F-statistics

2011-12-10 Thread Bert Gunter
This is not a statistical help list. Post to stats.stackexchange.com or a similar list to have someone tutor you in regression and explain why what you are doing is likely to produce utter nonsense. Or, better yet, get local statistical help in person. You also clearly need to do some reading on

Re: [R] efficiently finding the integrals of a sequence of functions

2011-12-10 Thread Hans W Borchers
JeffND Zuofeng.Shang.5 at nd.edu writes: Hi folks, I am having a question about efficiently finding the integrals of a list of functions. We had the same discussion last month under the heading performance of adaptIntegrate vs. integrate, see

Re: [R] Titelpage pdf-manual, packaging

2011-12-10 Thread Uwe Ligges
On 09.12.2011 14:15, Johannes Radinger wrote: Hi, I am trying to get write my first own package. I followed the instructions in Creating R Packages: A Tutorial and Writing R Extensions. So far everything works really fine, the script works and even the man-pages don't show any problems during

Re: [R] Overlaying density plot on forest plot

2011-12-10 Thread JeffND
Frank, Have you tried the R function overlay(), it is exactly applying to your question. Jeff -- View this message in context: http://r.789695.n4.nabble.com/Overlaying-density-plot-on-forest-plot-tp4179654p4180430.html Sent from the R help mailing list archive at Nabble.com.

Re: [R] Regression Models

2011-12-10 Thread JeffND
So your question is about fitting a regression model for all the subsets of predictors? Then there would be 2^13 submodesl? Probably leaps() does what you want. This function does a all-subset regresion. -- View this message in context:

[R] PCA on high dimentional data

2011-12-10 Thread mail me
Hi: I have a large dataset mydata, of 1000 rows and 1000 columns. The rows have gene names and columns have condition names (cond1, cond2, cond3, etc). mydata- read.table(file=c:/file1.mtx, header=TRUE, sep=) I applied PCA as follows: data_after_pca- prcomp(mydata, retx=TRUE, center=TRUE,

Re: [R] PCA on high dimentional data

2011-12-10 Thread Stephen Sefick
By doing PCA you are trying to find a lower dimensional representation of the major variation structure in your data. You get PC* to represent the new data. If you want to know what loads on the axes then you need to look at the loadings. These are the link between the original data and the

Re: [R] Regression Models

2011-12-10 Thread Stephen Sefick
regsubsets in leaps glmnet has lasso etc. too On Sat 10 Dec 2011 09:54:16 AM CST, JeffND wrote: So your question is about fitting a regression model for all the subsets of predictors? Then there would be 2^13 submodesl? Probably leaps() does what you want. This function does a all-subset

Re: [R] what is the difference between using function predict() and coef() in prediction

2011-12-10 Thread tony333
X8 = c(0.42808332, 0.14058333, 0.30558333, 0.09558333, 0.01808333, -0.09191666, -0.11441666, -0.12941666, 0.13808333, -0.31691666, 0.25308333 ,-0.20941666 ,0.02808333, -0.04441667, -0.43691666) xy.lm = lm(Y~X8) z = predict(xy.lm,list(X8=X8)) sz = coef(xy.lm)[1]+(coef(xy.lm)[2])*X8 is

Re: [R] what is the difference between using function predict() and coef() in prediction

2011-12-10 Thread tony333
X8 = c(0.42808332, 0.14058333, 0.30558333, 0.09558333, 0.01808333, -0.09191666, -0.11441666, -0.12941666, 0.13808333, -0.31691666, 0.25308333 ,-0.20941666 ,0.02808333, -0.04441667, -0.43691666) Y =c(370.6 , 887.6 ,3610.88333 , 435.1 , 1261.38333 , -741.11667,-3231.36667

Re: [R] what is the difference between using function predict() and coef() in prediction

2011-12-10 Thread David Winsemius
On Dec 10, 2011, at 11:48 AM, tony333 wrote: X8 = c(0.42808332, 0.14058333, 0.30558333, 0.09558333, 0.01808333, -0.09191666, -0.11441666, -0.12941666, 0.13808333, -0.31691666, 0.25308333 ,-0.20941666 ,0.02808333, -0.04441667, -0.43691666) xy.lm = lm(Y~X8) z =

Re: [R] PCA on high dimentional data

2011-12-10 Thread Mark Difford
On Dec 10, 2011 at 5:56pm deb wrote: My question is, is there any way I can map the PC1, PC2, PC3 to the original conditions, so that i can still have a reference to original condition labels after PCA? deb, To add to what Stephen has said. Best to do read up on principal component

Re: [R] PCA on high dimentional data

2011-12-10 Thread Bert Gunter
... and adding to what has already been said, PCA can be distorted by non-ellipsoidal distributions or small numbers of unusual values. Careful (chiefly graphical) examination of results is therefore essential, and usually fairly easy to do. There are robust/resistant versions of PCA in R, but

[R] p-value for hazard ratio in Cox proportional hazards regression?

2011-12-10 Thread Thierry Julian Panje
Hi, I'm new to R and using it for Cox survival analysis. Thanks to this great forum I learned how to compute the HR with its confidence interval. My question would be: Is there any way to get the p-value for a hazard ratio in addition to the confidence interval? Thanks, Thierry --

[R] Difficult subset challenge

2011-12-10 Thread Noah Silverman
Hi, I'm having difficulty coming up with a good way to subest some data to generate statistics. My data frame has multiple observations by group. Here is an overly-simplified toy example of the data == codev1 v2 G1 1.2 2.3 G1 0

Re: [R] p-value for hazard ratio in Cox proportional hazards regression?

2011-12-10 Thread Joshua Wiley
Hi Thierry, Could you give us an example of what exactly you are doing (preferablly reproducible R code)? I may be misunderstanding you, but if you are fitting cox proportional hazard models using the coxph() function from the surival package, summary(yourmodel) should give the SE, p-value based

Re: [R] Difficult subset challenge

2011-12-10 Thread Joshua Wiley
Hi Noah, I am unclear if the 0s should be standardized or not---I am assuming since you want them excluded from the calculation of the mean and SD, you do not want (0 - M) / sigma. If that is the case, here is an example: ## read in your data ## FYI: providing via dput() would be easier next

Re: [R] Kaplan-Meier survfit problem

2011-12-10 Thread capitantyler
done it, again, i have the next problem my traduction: The object (list) cannot be corced as double Original: *km1 - survfit(Surv(as.numeric(T.201110))~1)* Error en Surv(as.numeric(T.201110)) : el objeto (list) no puede ser coercionado a 'double' note that need it convert to numeric class,

Re: [R] Kaplan-Meier survfit problem

2011-12-10 Thread David Winsemius
On Dec 10, 2011, at 6:39 PM, capitantyler wrote: done it, again, i have the next problem my traduction: The object (list) cannot be corced as double Original: *km1 - survfit(Surv(as.numeric(T.201110))~1)* Error en Surv(as.numeric(T.201110)) : el objeto (list) no puede ser coercionado a

[R] as.factor does not work inside function

2011-12-10 Thread Xiaobo Gu
Hi, I am trying to write a function do cast columns of data frame as factor in a loop, the source is : as.factor.loop - function(df, cols){ if (!is.null(df) !is.null(cols) length(cols) 0) { for(col in cols) { df[[col]] -

Re: [R] as.factor does not work inside function

2011-12-10 Thread Xiaobo Gu
I am sorry, it is for(col in c(x,y)){df[[col]] - as.factor(df[[col]])} is.factor(df[[x]]) TRUE On Sun, Dec 11, 2011 at 10:06 AM, Xiaobo Gu guxiaobo1...@gmail.com wrote: Hi, I am trying to write a function do cast columns of data frame as factor in a loop, the source is : as.factor.loop

Re: [R] as.factor does not work inside function

2011-12-10 Thread Joshua Wiley
Hi Xiaobo, The problem is that your function is not assigning the results to your data frame---df is an internatl copy made by the function. This is done to prevent calling functions to have unexpected events such as overwriting objects in the global environment. Anyway, I think you can

Re: [R] as.factor does not work inside function

2011-12-10 Thread Xiaobo Gu
Hi Josh, Your suggesstion works, and the following also works: as.factor.loop - function(df, cols){ if (!is.null(df) !is.null(cols) length(cols) 0) { for(col in cols) { df[[col]] - as.factor(df[[col]]) } }

[R] incomplete final line found warning

2011-12-10 Thread Xiaobo Gu
Hi, I saved the following as a UTF-8 encoded file named amberutil.r as.factor.loop - function(df, cols){ if (!is.null(df) !is.null(cols) length(cols) 0) { for(col in cols) { df[[col]] - as.factor(df[[col]]) }

Re: [R] p-value for hazard ratio in Cox proportional hazards regression?

2011-12-10 Thread Joshua Wiley
Hi Thierry, I see what you want now---a significance test for the HR specifically. See inline below On Sat, Dec 10, 2011 at 6:40 PM, Thierry Julian Panje tpa...@stanford.edu wrote: Hi Josh, Thank you for your quick response! In several papers the results of a Cox Regression were presented

Re: [R] incomplete final line found warning

2011-12-10 Thread David Winsemius
On Dec 10, 2011, at 10:01 PM, Xiaobo Gu wrote: Hi, I saved the following as a UTF-8 encoded file named amberutil.r as.factor.loop - function(df, cols){ if (!is.null(df) !is.null(cols) length(cols) 0) { for(col in cols) {