similar to: calculating AUCs for each of the 1000 boot strap samples

Please note is with replacement From: taby gathoni <tabieg@yahoo.com> To: R help <r-help@r-project.org> Sent: Thursday, March 10, 2011 11:53 AM Subject: [R] random sampling steps in R Dear all, Could someone assist me in random sampling steps/code in R? I have a main sample of 42 males and 165 females and I want to come up with about 1000 samples of 20 males and 20 females from

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

Hi all, I am having this error while trying to merge about 2 dataframes m_merge = merge(m_accts,m_op, by.y="CUST_ID",by.x="FORACID",all.y=TRUE,all.x=TRUE) Error: cannot allocate vector of size 10.0 Mb Taby [[alternative HTML version deleted]]

Dear R-users, I need some  assistance. I am running some interactive variables for categorical variables. I have dgen(2 levels converted to dummy variables)  and dtoe(4-levels also converted to  dummy variables). So I have worked with them in two ways: i created a variable X1 = dgen*dtoe  and I get an error "Error in dgen * dtoe : non-conformable arrays"then i run a glm, binomial

Dear r user, please find my attached sample of the dataset i? am using to create a crosstable and eventually plot a histogram from the output. I am using? the cut2 function to create bins, about 7 of them using the code after reading the data: cluster <- cut2(cross_val$value, g=7) I get the warning: Warning message: In min(xx[xx > upper]) : no non-missing arguments to min; returning Inf

Hi all, Please help, I am getting an error when I try installing rattle. Error in as.GType(type) : Cannot convert RGtkBuilder to GType I have already installed gtk-2.12.9-win32-2  and gtk2-runtime-2.22.0-2010-10-21-ash and restarted R as instructions require. Please assist me Taby [[alternative HTML version deleted]]

Dear all, Could someone assist me in random sampling steps/code in R? I have a main sample of 42 males and 165 females and I want to come up with about 1000 samples of 20 males and 20 females from this main sample. While at it, i would also like to come up Accuracy Ratios (ARs) with corresponding confidence intervals. Please assist. Thanks so much, Taby [[alternative HTML version

Hi all, Out of curiosity I googled my name yesterday to just see what new information  in the web there is associated with me. To  my surprise, I found in addition to the  questions i have posted on this forum, my email address and my signature details (name, address, telephone number) seem to appear everytime i pose a question. How can i conceal my personal details from the access of anyone when

Dear all, i have a dataset of about 400 records , with a variable that has  two levels 40 bad and 360 good among other variables,how do i come up  with10 random samples that have the composition of as the main sample  but maintaining the 40 bad 360 good with replacement, i recently discovered that my random samples generated dont maintain the ratio. My code is as  : mysample <-

Hi, I am passing a data frame and field name to a function. I've figured out how I can create the formula based on the passed in field name, but I'm struggling to create a vector based in that field. for example if I hard code with the actual field name Y = df$Target, everything works fine. but if I use the passed in parameter name, it doesn't give me what I want, Y =

Hi, I am passing a data frame and field name to a function. I've figured out how I can create the formula based on the passed in field name, but I'm struggling to create a vector based in that field. for example if I hard code with the actual field name Y = df$Target, everything works fine. but if I use the passed in parameter name, it doesn't give me what I want, Y = df$mytarget

I am currently trying to transpose some large panel data set ie transposing multiple rows in into a single column. instead the transpose functionality transposes all rows into columns. my sample data set looks like below: ACCT_NUM ACCOUNT_NAME TRAN_AMT DATE EMPLOYER 101913 GK 7489 30-Apr-10 PENSION 101913 GK 7489 30-May-10 PENSION 101913

I am doing a simulation with a relatively large data set (20,000 observations) for which I want to calculate the area under the Receiver Operator Curve (AUC) for many parameter combinations. I am using the ROC library and the following commands to generate each AUC: rocobj=rocdemo.sca(truth = ymis, data = model$fitted.values, rule = dxrule.sca) #generation of observed ROC object

I have a situation when I need to save matrix with file names that are programmatically created. for (i in levels(mergeTrn$Continent)) { matrix here.... # I want to save this matrix with a file name that carries "i" from for loop. The following does not work. paste("plotroc_GBM_Trn_", i, sep="") <- matrix } Thanks, Kumar -- Section of Integrative

Within an user function, how are the warnings from an R function be trapped (such that some proper actions can be taken)? 'last.warning' is returned only at the top level. Pointers are appreciated. -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info",

Hi R-users, This is a generic question, is there a way to plot a line graph for the output from crosstable function? one of the inputs to the crosstab function is categorical. Taby -- [[alternative HTML version deleted]]

Dear All, Using RODBC I have read in a (429 x 11) dataframe from Access, and would like to append two columns of transformed data (429 x 2) to the original table (thereby making it a 429 x 13 table). I would ideally like this to be the same name etc as the original table in Access. I have used the following command: R>

Hi I am trying to perform a bootstrap estimate of classification accuracy of a logistic regression using the 'Daim' package in r using the code at the bottom of this post, this all works great and I get the .632+ misclassification accuracy, specificity, sensitivity, AUC etc etc but what I would like is to access the list of AUC for each of the bootstrap samples as I need calculate the 95%

Hi, I am quite new to R and I have two questions regarding ROCR. 1. I have tried to understand how to extract area-under-curve value by looking at the ROCR document and googling. Still I am not sure if I am doing the right thing. Here is my code, is "auc1" the auc value? " pred1 <- prediction(resp1,label1) perf1 <- performance(pred1,"tpr","fpr") plot(

Dear All,   I have the following example:   a <-matrix(c(1:100),ncol=10) b <-matrix(c(2,4,6,8,10,12,14,16,18,20))   trapz(b,a)   will give me a result of 99, which it seems to me is the AUC of the 1st column only. Is it possible to get the AUC results by columns of "a" using the same "b" values in the calculations as opposed to just generating the result for the 1st