similar to: select observations from longitudinal data set

Suppose I have a long format for a longitudinal data id time x 1 1 10 1 2 11 1 3 23 1 4 23 2 2 12 2 3 13 2 4 14 3 1 11 3 3 15 3 4 18 3 5 21 4 2 22 4 3 27 4 6 29 I want to select the x values for each ID when time is equal to 3. When that observation is not observed, then I want to replace it with the obervation at time equal to 4. otherwise just use NA. How can I implement this with a quick

i have a large longitudinal data set. The number of observations for each subject is not the same across the sample. The largest number of a subject is 5 and the smallest number is 1. now i want to make each subject to have the same number of observations by filling zero, e.g., my original sample is id x 001 10 001 30 001 20 002 10 002 20 002 40 002 80 002 70 003 20 003 40 004 ...... now i wish

i have a data set with repeated measures on same people, structure like below: id x1 x2 ... 001 10 20 ... 001 8 45 ... 001 4 2 ... 002 .... 002 ... 002 .... 002 .... 003 .... ....... what is the easist way to show how many observations for each subject id? [[alternative HTML version deleted]]

I have the complete data like id time censor 1 10 0 1 20 0 1 30 0 2 10 0 2 20 1 2 30 0 2 40 0 3 10 0 3 20 0 3 30 1 .... for id 1, i want to select the last row since all censor indicator is 0; for id 2, i want to select the row where censor ==1; for id 3, i also want to select the row where censor==1. So if there is a 1 for censor, then I want to select such a row, otherwise I want to select the

Hi, I'm fairly new to R but I have a large dataset (300000 obs) containing patient material. Some patients came 2-9 times during the three year observation period. The patients are identified by a unique idnr, the sessions can be distinguished using the session date. How can I recode the date of the session to a session id (1-9). This would be necessary to obtain information and do some

I used gam for data analysis a lot. Is it possible to use gam to analyze longitudinal data? I mean, besides the working independence assumption, can i specify other more reasonable covariance structure in gam? [[alternative HTML version deleted]]

Dear r-helpers, I have a very simple question. Suppose my data is like id=c(rep(1,2),rep(2,2)) b=c(2,3,4,5) m=cbind(id,b) > m id b [1,] 1 2 [2,] 1 3 [3,] 2 4 [4,] 2 5 I wish to select the first observation for each id. That is, I want to quickly select two rows: id b 1 2 2 4 only. how should i do this? [[alternative HTML version deleted]]

Dear R List, I am trying to use mixed models to analyze an intervention and want to make sure I am doing it correctly. The intervention is for lowing cholesterol and there are two groups: one with an intervention and one without. The subjects were evaluated a differing amount of time, so there were between 2 and 7 visits, equally spaced. Sample output is below. TC is total cholesterol,

hello, I have a longitudinal data: idn mort30 newinfec 1 0 1 1 0 1 1 0 1 1 0 1 2 1 1 2 1 1 2 1 1 3 0 0 3 0 0 3 0 0 3 0 0 3

First I would like to say thank you for taking the time to read it.Here is my problem. I am running a lmer analysis for binary longitudinal (repeated measures) data. Basically, I manipulated fruits and vegetation to two levels each(present and absent) and I am trying to access how these factors affect mice foraging behavior. The design consist of 12 plots, divided in 3 blocks. So each block

Hi Ruser I'm trying to replicate some SAS code. I have to add a spline to my longitudinal spaghetti plot. I have the plot, but I can't add the spline, a overall trend line. In the SAS code they use the command 'I=SM50S' and I would prefer something similar. I?m using R 2.10.1 on windows XP? I have made this working example. tolerance.pp <-

Dear R users, I was wondering if anyone knows how to obtain(subset) the first and/or the last record of a subject in a longitudinal setup. Normally in SAS one uses first.variable1 and last.variable1. So my question is that is there an R way of doing this. Regards, -- Luwis Diya, Phd student (Biostatistics), Biostatistical Center, School Of Public Health, Catholic University of Leuven, U.Z. St

Complete newbie to R -- struggling with something which should be pretty basic. Trying to create a simple data set (which I gather R refers to as a data.frame). So > a <- c(1,2,3,4,5); > b <- c(0.3,0.4,0.5,0,6,0.7); Stick the two together into a data frame (call test) using cbind > test <- data.frame(cbind(a,b)) Seems to do the trick: > test a b 1 1 0.3 2 2 0.4 3 3

Dear All, ? Let: dp: depth of the river tp: temperature with respect to depth These pair of observations are in 3 different groups i.e: Obs. 1,3,5,7?from the first group Obs. 2,4 and?10?from second group Obs 6,8 and 9?from third group. We can have a simple scatter plot, between depth as y-axis and temperature as x-axis, with each pairs are denoted by a red dot, by using a plot function shown

I have the following list of observations of calendar time: [1] 03-Nov-1997 09-Oct-1991 27-Aug-1992 01-Jul-1994 19-Jan-1990 12-Nov-1993 [7] 08-Oct-1993 10-Nov-1982 08-Dec-1986 23-Dec-1987 02-Aug-1995 20-Oct-1998 [13] 29-Apr-1991 16-Mar-1994 20-May-1991 28-Dec-1987 14-Jul-1999 27-Nov-1998 [19] 09-Sep-1999 26-Aug-1999 20-Jun-1997 05-May-1995 26-Mar-1998 15-Aug-1994 [25] 24-Jun-1996 02-Oct-1996

Hi, I would liek to ask the list if any one can explain why there should be a discrepency in the directory sizes that are displayed when I use explorer on Windows. This has been reported to me by a user, I have never seen this before as I dont use windows if I can help it :-)... When I slect properties of a directory it has two enties Size and Size on disk As an example size says 33 bytes, size

I have a matrix of the following form: time id 0 2 4 6 9 12 14 3 9 8 NA NA NA NA NA 7 3 NA 3 NA 3 NA 4 13 11 6 7 NA 5 NA 6 ..... I hope for each row to select the last observation which is not 'NA'. For example, for the first row, id=3, the value I want to select is 8 for the second row, id=7, the value I want to select is 4 for the third row, id=13, the

I have a longitudinal competing risk data of the form: ID COMPL SEX HEREDITY 1 0 1 2 1 0 1 2 1 3 1 2 2 0 0 1 2 1 0 1 2 2 0 1 2 2 0 1 3 0 0 1 3 0 0 1 3 0 0 1 3 0 0 1 3 2 0 1 4 0 1 2 4 0 1

Hi, It is not that clear. If VAR1 is a match between columns AB001A, AB0002A, VAR2? between AB001A, AB362 and VAR3 between AB0002A and AB362: Also, I assume row8 match would be taken as 1. dat1<- read.table(text=" ? S.No AB001A AB0002A AB362 ?? 1?? -/-??????? C/C?? A/A??????????????????????? ??? 2?? C/C??????? C/C?? A/A??????????????????????? ??? 3?? C/C??????? C/C??

I have the following data ID x y time 1 10 20 0 1 10 30 1 1 10 40 2 2 12 23 0 2 12 25 1 2 12 28 2 2 12 38 3 3 5 10 0 3 5 15 2 ..... x is time invariant, ID is the subject id number, y is changing over time. I want to find out the difference between the first and last observed y value for each subject and get a table like ID x y 1 10 20 2 12 15 3 5 5 ...... Is there any easy way to generate