similar to: How to simulate correlated data

Displaying 20 results from an estimated 3000 matches similar to: "How to simulate correlated data"

2006 Dec 07
2
How to use read.xls in R
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
2005 Jun 09
1
question on boot
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
2004 Sep 09
1
Blom's approximation to rankits?
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
2005 Nov 08
3
how to draw cumulative histogram
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
2005 Jun 28
2
How to sort a dataframe by one variable
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
2005 Nov 23
2
wilcoxon.test?
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
2006 Jan 04
2
How to produce this graphic
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
2006 Feb 09
2
latent class modle for rater agreement
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
2006 Mar 08
2
How to plot the xaxis label at 45 degree angle?
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
2004 Jul 21
2
How to do a "go to " in a loop 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,
2004 Dec 06
1
The survival rate at a certain time
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:
2005 May 18
2
Why can't I download "window binary" zip packages
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
2006 Feb 13
1
LCA in e1071
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
2005 Dec 04
4
Construct a data.frame in a FOR-loop
Say I have a FOR-loop for computing powers (just a trivial example) for(i in 1:5) { x<-i^2 y<-i^3 } How can I create a data.frame and a 3D plot of (i,x(i),y(i)), i.e. for each iteration Thanks, Serguei Kaniovski -- ___________________________________________________________________ ??sterreichisches Institut f??r Wirtschaftsforschung (WIFO) Name: Serguei Kaniovski
2005 Dec 06
2
how to extract row& col names from a matrix
Dear all, I like to extract row names & column names from the named matrix...... like...... a<-matrix(1:6,2) ro<-c("aa","bb") co<-c("dd","ee","ff") dimnames(a)<-list(ro,co) a > dd ee ff aa 1 3 5 bb 2 4 6 from the above matrix "a" I like to extract rownames separately like
2005 Dec 17
1
How to reverse the sequence of axis Y ??
Hello R-users! My (simple?) doubt: How to reverse the sequence of axis Y ?? the diagram below illustrate my idea... (default) | | . | . | . | 3 | 2 | 1 | 0 +---------------------------- 0 1 2 3 ... like I want... 0 | 1 | 2 | 3 | . | . | . | | +---------------------------- 0 1 2 3 ... thanks in advance klebyn
2005 Dec 06
4
R newbie...
Hello, I'm a new user... I have a function : calculate <- function(x,y) { z <- x + y } I would like to use the result (z) with another function : recalculate <- function(...) { a <- z^2 } But R says that z does not exist... How can I use z in an another function ? Thank you for your answer... -- David [[alternative HTML version deleted]]
2005 Dec 09
3
R-how to group the data
Hello R - users, This may sound simple to may people: I have a list of data as follows type value y 7 y 7 y 8 y 8 y 8 y 9 y 9 y 9 y 9 y 10 y 10 y 10 y 10 y 11 y 11 y 12 y 12 y 14 y 14 y 14 y 15 y 17 y 20 y 20 y 20 y 20 y 25
2005 Nov 04
2
Simplify iterative programming
Dear, I am looking for the simplification of a formula to improve the calculation speed of my program. Therefore I want to simplify the following formula: H = sum{i=0..n-1 , [ sum {j=0..m-1 , sqrt ( (Ai - Bj)^2 + (Ci - Dj)^2) } ] } where: A, C = two vectors (with numerical data) of length n B, D = two vectors (with numerical data) of length m sqrt = square root Ai = element of A with index
2005 Dec 06
2
Writing a list to a file !
Hi All, This may be trivial in R but I have been trying with out any success. I have a list of 100 elements each having a sub list of different length. I would like to write the list to a ASCII file. I tried with write.table(), after converting my list to a matrix. Now it looks like Robert c("90", "50", "30") John c("91", "20",