search for: tu_chunhao

Displaying 7 results from an estimated 7 matches for "tu_chunhao".

2009 Sep 08
2
strange results in summary and IQR functions
Dear R users, Something is strange in summary and IQR. Suppose, I have a data set and I would like to find the Q1, Q2, Q3 and IQR. x<-c(2,4,11,12,13,15,31,31,37,47) > summary(x) Min. 1st Qu. Median Mean 3rd Qu. Max. 2.00 11.25 14.00 20.30 31.00 47.00 > IQR(x) [1] 19.75 However, I test the same data set in SAS "proc univariate", and SAS shows that
2009 Jun 12
1
Please Help pairwise.t.test!!
Hi R users, My question is, If I have 3 groups, A, B, C and I know mean of A =20, B=21, and C=20.5 and I also know the standard error of A =1.1, B=2.2, C=3.2. Plus, I know A has 30 observations, B has 78, C has 45. But I do not have the raw data. Can I use pairwise.t.test to conduct a Bonferroni test? If yes, Could you give me a hint? Thank you so much Chunhao -- View this message in
2009 Sep 29
4
Something wrong with my function Please Help
Hi R users, I try to build a function to compute odds ratio and relative risk however something wrong. I stuck for many hours but I really don't know how to solve it. Would someone please give me a hint? > OR.RR<-function(x){ + x <- as.matrix(any(dim(x)==2)) + OR<-(x[1,1]*x[2,2])/(x[1,2]*x[2,1]) + RR<-(x[1,1]/(sum(x[1,])))/(x[2,1]/(sum(x[2,]))) +
2009 Dec 18
0
Compare two repeated measures mixed models
Hi R users, I have a statistical question. If I have two repeated measures models such as, m1, y=u+a+time+a:time+e m2, y=u+b+time+b:time+e How can I compare these two models (such as which one is the better predictor, a or b)? Many Thanks In Advance. Chunhao -- View this message in context: http://n4.nabble.com/Compare-two-repeated-measures-mixed-models-tp974511p974511.html Sent from the R help
2010 Sep 05
2
Need Help .RData in Mac OS X, Please
Hi R Users, I was accidentally save R file when I quit R program. I try to delete but I am not sure the R saved file was successfuly delete or not. Now everyt time when I open the R, it always appears [R.app GUI 1.34 (5589) i386-apple-darwin9.8.0] [Workspace restored from /Users/ctu/.RData] I have read google, R help and Nabble but I still can't solve this problem. Could someone please
2009 Sep 09
2
The code behind the function
Hi R users, I have a question. How can I see the code behind the function. For example, > boxplot function (x, ...) UseMethod("boxplot") <environment: namespace:graphics> I really would like to see how people code this. Could someone please show me how to see the code behind the function? Many Thanks Tu -- View this message in context:
2010 Feb 23
3
Use 2 "ifelse" to sort data
Dear R users, I have a question how to use 2 "ifelse" to sort my data. Such as from 11 to 20 assign to A; 6 to 10 assign to B, and the rest of them assign to C a<-1:20 tt<-ifelse(a>10, "A",no=ifelse( 5< a <=10, "B", "C")) Many Thanks Chunhao -- View this message in context: