similar to: LCA in e1071

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

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,

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 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

Hello there, In gdata package, read.xls is to be used for reading excel data (from windows). The following is my code:('C:/session/sampledata.xls' is where the file is stored) data1<-read.xls('C:/session/sampledata.xls',sheet=1) and I got the following error message: Error in system(cmd, intern = !verbose) : perl not found Could you please tell me what I have done wrong and

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, I will use the lca method in the e1071 package. But I get the following error: Error in pas[j, ] <- drop(exp(rep(1, nvar) %*% log(mp))) : number of items to replace is not a multiple of replacement length Does anybody know this error and knows what this means? Kind regards, Tryntsje

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, 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

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

It sounds as thought you are interested in Hoyt's Anova which is a form of generalizability theory. This is usually estimated using by getting the variance components from ANOVA. > -----Original Message----- > From: r-help-bounces at stat.math.ethz.ch > [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Karl Knoblick > Sent: Tuesday, May 16, 2006 6:10 AM > To: r-help at

Hello! I want to calculate the intra- and interrater reliability of my study. The design is very simple, 5 raters rated a diagnostic score 3 times for 19 patients. Are there methods/funtions in R? I only found packages to calculate interrater variability and intraclass correlation coefficients for matrices of n*m (n subjects, m raters) - I have n subjects, m raters and r repetitions. Can

Hi All: Could anyone point me to a package that can calculate stratified kappa? My design is like this, 4 raters, 30 types of diagnosis scores, 20 patients. Each rater will rate each patient for each type of diagnosis score. The rater's value is nominal. I know I can measure the agreement between raters for each type of diagnosis score, e.g., calculate out 30 kappa values. My problem is I

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

Karl, If you use one of the specialized packages to calculate your ICC, make sure that you know what you're getting. (I haven't checked the packages out myself, so I don't know either.) You might want to read David Futrell's article in the May 1995 issue of Quality Progress where he describes six different ways to calculate ICCs from the same data set, all with different

Hi All, I am using fleiss kappa for inter rater agreement. Are there any know issues with Fleiss kappa calculation in R? Even when I supply mock data with total agreement among the raters I do not get a kappa value of 1. instead I am getting negative values. I am using the irr package version 0.70 Any help is much appreciated. Thanks and Regards M [[alternative HTML version deleted]]

Hello All, I'm one of the organisers for The Australian Linux Technical Conference called linux.conf.au (LCA for short). At LCA we are having mini-conferences. These mini-confs are not officially part of the main LCA but are aimed at specific subsections of the (Australian) Linux community. Currently at LCA2003 we have a confirmed Debian mini-conf SAGE-AU (Systems Administrators Guild of

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