search for: biostatistiek

Displaying 20 results from an estimated 99 matches for "biostatistiek".

Did you mean: biostatistics
2010 Nov 09
3
Row-wise recurive function call
Dear Group, I have a following dataset: > a A B C D 1 22 3 31 40 2 26 31 36 32 3 3 7 49 16 4 24 40 27 26 5 20 45 47 0 6 34 43 11 18 7 48 48 24 2 8 3 16 39 48 9 20 49 7 21 10 17 36 47 10 > dput(a) structure(list(A = c(22L, 26L, 3L, 24L, 20L, 34L, 48L, 3L, 20L, 17L), B = c(3L, 31L, 7L, 40L, 45L, 43L, 48L, 16L, 49L, 36L), C = c(31L, 36L, 49L, 27L, 47L, 11L, 24L,
2012 Apr 20
3
Matrix multiplication by multple constants
Dear R helpers Suppose x  <- c(1:3) y  <- matrix(1:12, ncol = 3, nrow = 4) > y      [,1] [,2] [,3] [1,]    1    5    9 [2,]    2    6   10 [3,]    3    7   11 [4,]    4    8   12 I wish to multiply 1st column of y by first element of x i.e. 1, 2nd column of y by 2nd element of x i.e. 2 an so on. Thus the resultant matrix should be like > z      [,1]   [,2]    [,3] [1,]    1   
2010 Nov 07
3
regular exprs
...39;t managed to succeed. Thanks in advance. Best, Dimitris -- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014 Web: http://www.erasmusmc.nl/biostatistiek/
2011 Aug 23
4
Correlation discrepancy
Dear R list, I have one very elementary question regrading correlation between two variables. x = c(44,46,46,47,45,43,45,44) y = c(44,43,41,41,46,48,44,43) > cov(x, y) [1] -2.428571 However, if I try to calculate the covariance using the formula as covariance = sum((x-mean(x))*(y-mean(y)))/8       # no of of paired obs. = 8 or     covariance = sum(x*y)/8-(mean(x)*mean(y)) gives
2012 Nov 01
3
convert list without same component length to matrix
Hi, I have this lame question. I want to convert a list (each with varies in length) to matrix with same row length by eliminating vectors outside the needed range. For example: l<-list(NULL) l[[1]]=1,2,3.7 l[[2]]=3,4,5,6,3 l[[3]]=4,2,5,7 l[[4]]=2,4,6,3,2 l[[5]]=3,5,7,2 #so say I want to only have 4 rows and 5 column in my matrix (or data.frame) and eliminating the 5th index value in l[[2]]
2010 Oct 15
4
split data with missing data condition
Dear all I have data like this: x y [1,] 59.74889 3.1317081 [2,] 38.77629 1.7102589 [3,] NA 2.2312962 [4,] 32.35268 1.3889621 [5,] 74.01394 1.5361227 [6,] 34.82584 1.1665412 [7,] 42.72262 2.7870875 [8,] 70.54999 3.3917257 [9,] 59.37573 2.6763249 [10,] 68.87422 1.9697770 [11,] 19.00898 2.0584415 [12,] 60.27915 2.5365194 [13,] 50.76850
2010 Dec 15
0
package JM -- version 0.8-0
..., bug-reports, etc.) is more than welcome. Best, Dimitris -- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014 Web: http://www.erasmusmc.nl/biostatistiek/ _______________________________________________ R-packages mailing list R-packages at r-project.org https://stat.ethz.ch/mailman/listinfo/r-packages
2011 Sep 04
2
Regression coefficient constraints
Hi Guys, Does anyone know how I could constrain my regression coefficients so that they are positive and add up to one? Any help will be greatly appreciated. Kind Regards, Andre [[alternative HTML version deleted]]
2010 Oct 21
1
How to check for missing report pages per client
Hi, Not sure how to go about checking for missing report pages per client. See example below; I like to extract client 730040, because page 46103 is missing. client page 730001 46101 730001 46102 730019 46101 730035 46101 730040 46101 730040 46102 730040 46104 730040 46105 730052 46101 730052 46102 730074 46101 730074 46102 730074 46103 I appreciate any help, Pauline
2010 Nov 17
2
slicing list with matrices
A list contains several matrices. Over all matrices (list elements) I'd like to access one matrix cell: m <- matrix(1:9, nrow=3, dimnames=list(LETTERS[1:3], letters[1:3])) l <- list(m1=m, m2=m*2, m3=m*3) l[[3]] # works l[[3]][1:2, ] # works l[[1:3]][1, 1] # does not work How can I slice all C-c combinations in the list? S?ren -- S?ren Vogel, Dipl.-Psych. (Univ.), PhD-Student, Eawag,
2010 Nov 25
1
Applying function to elements of matrices in a list
Hello R-help, Please cc me on all responses, as I only receive summary emails from this list. I'm wondering if anybody has any tips on how to accomplish this efficiently. I have a list of matrices, and I'm trying to get the mean of the [i,j]'th element of each matrix in a list. So if I have a list of matrices, say x <-
2010 Dec 15
0
package JM -- version 0.8-0
..., bug-reports, etc.) is more than welcome. Best, Dimitris -- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014 Web: http://www.erasmusmc.nl/biostatistiek/ _______________________________________________ R-packages mailing list R-packages at r-project.org https://stat.ethz.ch/mailman/listinfo/r-packages
2011 Feb 16
2
Axis positions
Hi everyone. I would like to modify the axis on my plot. First, I would like to make a plot without the box. so I use : plot(x,y, axes = FALSE, type = 'l') Then, I call : axis(1, tck = -0.02) axis(2, tck = -0.02) to have X and Y axis appear. However, I would like them to join at the origin instead of having a space between the 2 axis. I can't find the parameter to modify to get
2011 Jun 14
1
Expand DF with all levels of a variable
Dear list, I would like to expand a DF with all the missing levels of a variable. a <- c(2,2,3,4,5,6,7,8,9) a.cut <- cut(a, breaks=c(0,2,6,9,12), right=FALSE ) (x <- data.frame(a, a.cut)) # In 'x' the level "[0,2)" is "missing". AddMissingLevel <- function(xdf) { xfac <- factor( c("[0,2)", "[2,6)", "[6,9)",
2011 Jun 24
1
Fastest way of finding if any members of vector x fall in the range of the rows of matrix y
Hi All, What is the fastest way of finding if any members of vector x fall in the range of the rows of matrix y? I do not want to use two for loops as this will take forever. Any help will be appreciated, best, salih [[alternative HTML version deleted]]
2011 Aug 25
1
Bivariate normal regression in R
Hello everyone, I need to fit a bivariate normal regression model to a dataset where the same covariate (say, X) influences two separate but correlated responses (say, Y1 and Y2). So, the bivariate model would look like : Y1 = a1 + b1*X + e1 Y2 = a2 + b2*X + e2 where e1 and e2 are error terms which can be correlated. Is there any package in R which can help me fit this model ? Any help will be
2011 Aug 31
1
assign group letters to T/F matrix
dear R community, i appologize as this is kind of a newbie question, but: I want to assign group letters (like in anova post-hoc tests) to data with combined means and SDs. It's easy to apply t-test formulas to get a materix like (A - D are treatments | A B C D ----------------------- A| T F F B| T F C| F D| where true stands for sign.
2011 Sep 19
2
pasting elements of one character vector together
hello, i am familiar with the paste command with which i can paste for exaple: object <- "Hello" paste(object,"World") now i would like to be able to paste all the elements of the same vector together e.g: object <- c("Hello","World") getting as a result also: "Hello World". Does anyone know the solution to this problem? Thank you
2011 Sep 28
0
package JM -- version 0.9-0
...bug-reports, etc.) is more than welcome. Best, Dimitris -- Dimitris Rizopoulos Assistant Professor Department of Biostatistics Erasmus University Medical Center Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands Tel: +31/(0)10/7043478 Fax: +31/(0)10/7043014 Web: http://www.erasmusmc.nl/biostatistiek/ _______________________________________________ R-packages mailing list R-packages at r-project.org https://stat.ethz.ch/mailman/listinfo/r-packages
2011 Sep 29
1
multiplying list with vector
hello everybody, i have got a question about lists: i have got the following commands: mylist <- list("v1"=c(1,2,2,1),"v2"=c(2,2,2,1),"v3"=c(1,1,1,1)) myvector <- c(100,10000,1000000) now i would like to multiply each element of the list with the corresponding element of the vector, that is to say: v1*100 v2*10000 v3*1000000 i only could think of lapply