similar to: How to use read.xls in R

Hi there, I'm writing a function which involves a loop. What to write in the "?" place would allow it skips the "for loop" and goes to "a[i]<-0". a<-b[s>3,] if (nrow(a)==0) ????????????? for (i in 1:nrow(a)){ a[i]<-1 } a[i]<-0 Lisa Wang Cancer Informatics, Ontario Cancer Institute/Princess Margaret Hospital,

Hello there, I am using R to plot some cumulative histogram for my data. Please help in this case. Thank you Lisa Wang Princess Margaret Hospital Toronto phone 416 946 4501 ext.4883

Hi there, Could anybody help me on how to sort a dataframe by one variable in the dataframe? Thank you Lisa Wang Princess Margaret Hospital Toronto, Ca tel: 416 946 4501

Hello there, I would like to test the agreement amongst 6 raters for nominal data on a scale from 1-4, and conduct a latent class analysis in R. How should the data be formatted and what code should I use? Thank you very much Lisa Wang Princess Margaret Hospital Biostatistics tel:416 946 4501

Hello there, I would like to simulate X --Normal (20, 5) Y-- Normal (40, 10) and the correlation between X and Y is 0.6. How do I do it in R? Thank you very much Lisa Wang Msc. Princess Margaret Hospital Toronto, Ca

Hello there, I would like to do a Wilcoxon matched pairs signed rank sum test in R and tried the function wilcoxon.test. Is it in the "base" library? If not, please let me know which library it is in. Thank you in advance for your help Lisa Wang Biostatistician Princess Margaret Hospital Toronto, Ca

Hello there, I would like to plot a graph with the x axis's label displayed at a 45 angle to the x axis instead of horizontal to it as the label is very long. What should I do? Thank you for your help in advance Lisa Wang Princess Margaret Hospital Toronto, Ca

Hello there, I am doing analysis on survival data. How do I pick out a probability of survival at a chosen landmark time(for example, 3 years, 4 years) from the result of "survfit"? or any other functions? As I know, the result of 'survfit' only have the probabilities for all event or cencor time. Thank you very much Lisa Wang Princess Margaret Hospital Toronto, Ca tel:

Hello there, I tried so many times to download windows binary zip package but it told me that I don't have the access to do so. It worked for me a few months ago. Please help me with it. Thank you Lisa Wang Msc. Princess Margaret Hospital Toronto , Canada tel: (416) 946 4501 ext.5201

Hello there, In the e1071 package,'lca' function only works for binary data for Latent class analysis. Am I right? I would like to test the agreement amongst 6 raters for nominal data ona scale from 1-4, and conduct a latent class analysis. What package and what function may I use? Thank you very much Lisa Wang Princess Margaret Hospital tel: 416 946 4501

Hello there: Dear Dr. Murdoch, I'm a statistician at Princess Margaret Hospital. Could you please help me with the bootstrapping? Can boot function (along with boot.ci) handle multivariate statistics? My intention is that I want to group the outcome data and evaluate the proportion of patients who are positive for a marker within each group. (i.e. I have two variables, a predictor and

Hello, My name is Lisa and I'm a statistician at Princess Margare Hospital. I wonder if there is any function in R that calculate the Normal rankits based on Blom's approximation? Thank you very much Lisa Wang Msc. Princess Margaret hospital Toronto, Ca

Hello there, I would like to produce a plot of x<-c(4,5,6),which is the mean of each group and y<-c('groupA','groupB','groupC'). plot (x,y) can not produce any graphics because y is not numerical. What should I do to produce this graphic? Thank you in advance Lisa Wang Princess Margaret Hospital Toronto,Ca

Hello there, My name is Lisa and I'm doing analysis using genelized linear model-GEE model because I have some repeated measurements on the same patients (in a bilateral eye disease case). It would be very appreciated if you could shed some light on what function to use in R. Thank you very much Lisa Wang Msc. Toronto,Ca

Hello, Could you please let me know how to see the "mean" function in R . The following is what I see when type in "mean" and "enter" mean function (x, ...) UseMethod("mean") <environment: namespace:base> I would like to see how the function is writen. Thanks a lot Lisa Wang Toronto, Ca -------------- next part -------------- This e-mail may

Hello, I'm a biostatistician in Toronto. I would like to know if there is anything in survival analysis developed in R for the method "Evaluating the Yield of Medical Test" (JAMA. May 14,1982--Vol 247, No.18 Frank E. Harrell, Jr,PhD; Robert M. Califf, MD; David B. Pryor, MD;Kerry L.Lee, PhD; Robert A. Rosait,MD.) Hope to hear from you and thanks Lisa Wang, MSc Project Organiser

I have written a function that contains runs lm() vif() and glm() When the glm() blows up with an error message, I don't get the output from either the lm() or vf() even thought neither lm() nor vif() have any problems . How can I force the function to print sequential results rather than wait for the entire function to complete before listing the functhion's output? Thanks, John

Good morning to everybody, I have a problem : how can I import excel files in R??? thank you very much Dr.sa. Erika Frigo Università degli Studi di Milano Facoltà di Medicina Veterinaria Dipartimento di Scienze e Tecnologie Veterinarie per la Sicurezza Alimentare (VSA) Via Grasselli, 7 20137 Milano Tel. 02/50318515 Fax 02/50318501 [[alternative HTML version deleted]]

Hello Dimitris, I was goggling for some help on Sensitivity vs 1-specificity and saw your link. I hope you can be of help to me in one of the issue that I am facing in generating combo chart(bar chart and plot). I am a novice and have some difficulty in getting this logic correct. I am give a dataset (I am attaching a sample dataset). I am using a barplot() and passing values for

Windows XP R 2.8.1 Colleagues, I am trying to run a function testone() and if the function completes without error do one set of instructions, and if the function generates either a warning or an error run another set of instructions. I have read try, and tryCatch help screens at least 20 times, have tried to experiment with code, but I can't understand how to accomplish my desired task.