similar to: Bland-Altman method to measure agreement with repeated measures

Displaying 20 results from an estimated 2000 matches similar to: "Bland-Altman method to measure agreement with repeated measures"

2011 Feb 24
1
accuracy of measurements
Dear R people Could you please help with following Trying to compare accuracy of tumor size evaluation by different methods. So data looks like id true metod1 method2 ... 1 2 2 2.5 2 1.5 2 2 3 2 2 2 etc. Could you please give a hint how to deal with that. Seems like {merror} does not suite to me because I am trying to compare accuracy of measurements with their true known values not just
2000 Apr 25
2
[R) Bland Altman plot (was: paste ?)
> De : Bill Venables <venables at acland.qld.cmis.csiro.au> > Objet : Re: [R] paste ? > Date?: mardi 25 avril 2000 08:45 > (...) > Secondly, I'm curious about the history of this kind of plot. > I've only heard it called a "Tukey mean difference" plot, (and > Trellis graphics has a function, tmd(), that does it, but no one > knows about it...).
2013 Jul 18
1
Bland Altman summary stats for all column combinations
Hello, I have the following data.frame structure(list(Study = structure(c(1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L, 15L, 16L, 17L, 18L, 19L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L, 15L, 16L, 17L, 18L, 19L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L, 15L, 16L, 17L, 18L, 19L, 1L, 2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L, 14L,
2011 Sep 20
5
help in interpreting paired t-test
Dear all; A very basic question. I have the following data: ************************************************************************************ A <- 1/1000*c(347,328,129,122,18,57,105,188,57,257,53,108,336,163, 62,112,334,249,45,244,211,175,174,26,375,346,153,32, 89,32,358,202,123,131,88,36,30,67,96,135,219,122, 89,117,86,169,179,54,48,40,54,568,664,277,91,290,
2010 Aug 25
2
Comparing samples with widely different uncertainties
Hi This is probably more of a statistics question than a specific R question, although I will be using R and need to know how to solve the problem in R. I have several sets of data (ejection fraction measurements) taken in various ways from the same set of (~400) patients (so it is paired data). For each individual measurement I can make an estimate of the percentage uncertainty in the
2000 Apr 26
1
Bland Altman plot (was: paste ?)
Dear all, sorry for this perhaps stupid question, but it concerns my recent problem as well as the current thread on B-A plot. I would like to plot something like x+y vs. x-y or mean(x,y) vs difference (x,y), but my "variables" x,y are actually pairs of replicates (two observed values of a growth rate by 60 clones). So the order x,y does not matter and each x,y pair can be arranged
2000 Apr 24
2
paste ?
Dear friends. I've made a very simple procedure to make Bland-Altman plots and it works OK except for the inability to take a variate as argument in annotation. I'm sure it is a very simple error, so if you have 5 seconds please tell me. Best wishes Troels bland <- function (x) #accepts two columns { mn <- 0.5*(x[,1]+x[,2]) diff <- x[,1]-x[,2]
2008 Dec 07
2
concordance correlation coefficient using R
Hi. I have data which i would want to assess the degree of agreement between two assays, e.g., to evaluate reproducibility or for inter-rater reliability. I have used the Pearson product-moment correlation coefficient. It looks good ranginging between 0.90 to 0.998. Though this looks good. I am told the Concordance correlation coefficient will give a better picture of how reproducible the assay
2011 Jan 18
2
ggplot2, geom_hline and facet_grid
Hi I have a long data set on which I want to do Bland-Altman style plots for each rhythm type Using ggplot2, when I use geom_hline with facet_grid I get an extra set of empty panels. I can't get it to do it with the "Diamonds" data supplied with the package so here is a (much abbreviated) example: > lvexs cvd_basestudy ecd_rhythm fixed_time variable_time 1 CBP05J02
2011 Mar 23
2
Estimating correlation in multiple measures data
Dear R-helpers, This may sound simple to you, but I'm a beginner in this, so please be forgiving. I have a following problem: two analytes were measured in patient's blood on 4 occasions: ProteinA and ProteinB. How to correctly evaluate correlation between ProteinA and ProteinB? I tried: x <- data.frame(Patient.ID=rep(1:10, each=4), Visit=rep(c(1:4),10), ProteinA=rnorm(m=10,
2001 Jul 10
1
Using R for Data Analysis & Graphics: update
There is now an updated version of "Using R for Data Analysis & Graphics" on CRAN, under Documentation | Contributed. Data sets and scripts are available from my web page, to which there is a link on the relevant CRAN page. John Maindonald email: john.maindonald at anu.edu.au phone : (6125)3473 fax : (6125)5549 Statistical Consulting Unit, Room 1194,
2011 Mar 23
2
Comparing non nested models with correlation coefficients (inspired from Lorch and Myers )
Hi, I would like to compare two models in R with the same dependant variable but different predictors (two different types of frequency and reaction times as RT). An editor told me to have a look at Lorch and Myers 1990. Lorch and Myers use the following technique: 1) they perform regressions on individual subjects' data 2) they extract the beta weights 3) they run t-test on these beta
2006 Mar 09
4
IVR woes
Hello all. I'm having a problem debugging an IVR I'm building. I can't see any reason this shouldn't be working. Firstly the asterisk version is: Asterisk SVN-trunk-r7230 built by root @ localhost.localdomain on a i686 running Linux on 2006-02-17 22:44:48 UTC Basically the problem is this. While the playbacks are happening you can push any one of the options and to happily
2011 May 05
6
Averaging uneven measurements by time with uneven numbers of measurements
I have a new device that takes measurements anywhere from every second, to every 15 minutes (depending on changes). The matrix has a date, time and Y column (Y is the measurement). For three days it is 25,000 rows. How do I average the measurements by every 30 minutes so my matrix is 48 rows per day? I have been working on this and cannot figure out a simple method. Any ideas? Thank you. ----- In
2006 Mar 11
2
IVR dial by extension option..
I'm working on an IVR that gives the users the option (number 5 in the main menu) to dial by extension: exten => 5,1,Set(TIMEOUT(digit)=5) ; Dial Extension exten => 5,2,Set(TIMEOUT(response)=10) exten => 5,3,Background(LCL/prompt-60) exten => 5,4,WaitExten(15) When going option 5 you can dial some extensions such as 2802, it goes to the extension (all extens start with 28 on the
2005 Apr 15
4
aggregation question
Is length(unique()) what you are looking for? Andy > From: Christoph Lehmann > > Hi I have a question concerning aggregation > > (simple demo code S. below) > > I have the data.frame > > id meas date > 1 a 0.637513747 1 > 2 a 0.187710063 2 > 3 a 0.247098459 2 > 4 a 0.306447690 3 > 5 b 0.407573577 2 > 6 b
2007 Sep 11
6
xyplot question
I have the code below and it works fine if I print the xyplot but if I take the print out, then I just get a blank pdf. The same holds if I just send the plot to the console without the print ( I get nothing ). My question is whether this is always the case with xyplot or is there something wrong with my settings ? I am on linux ( redhat ) and using R.2.5.0. Thanks. load("stocks.dat")
2006 Feb 12
1
lme, nlsList, nlsList.selfStart
Dear listers, I am trying to fit a model using nlsList() using alternately a SSfol() selfstart function or its developped equivalent formulae. This preliminary trial works well mydata<-groupedData(Conc~Tps|Organ,data=mydata) mymod1<-nls(Conc~SSfol(Dose,Tps,lKe,lKa,lCl),data=mydata) as well as a developped form: mymod2<-nls(Conc~Dose * exp(lKe+lKa-lCl) *
2005 Jul 28
1
conversion from SAS
Hi, I wonder if anybody could help me in converting this easy SAS program into R. (I'm still trying to do that!) PROC IMPORT OUT= WORK.CHLA_italian DATAFILE= "C:\Documents and Settings\carleal\My Documents\REBECCA\stat\sas\All&nutrients.xls" DBMS=EXCEL2000 REPLACE; GETNAMES=YES; RUN; data chla_italian; set chla_italian;
2011 May 12
1
separate date and time
I have a combined date and time. I would like to separate them out into two columns so I can do things such as take the mean by time across all dates. meas<-runif(435) nTime<-seq(1303975800, 1304757000, 1800) nDateT<-as.POSIXct(nTime, origin="1970-01-01") mat1<-cbind(nDateT,meas) means1<- aggregate(mat1$meas, list(nDateT), mean) This doesn't do anything as each day