search for: lm_mengxin

Hi all: My OS is 32bit winxp,but I wanna install 64bit R2.14.1. >From the following website,it says "You can also go back and add 64-bit components to a 32-bit install, or vice versa" http://cran.r-project.org/bin/windows/rw-FAQ.html#Can-both-32_002d-and-64_002dbit-R-be-installed-on-the-same-machine_003f Does it mean that I can install and run 64bit R2.14.1 under 32bit

Hi all: My data has 3 variables: age(3levels : <30y=1 30-50y=2, >50y=3) gender(Male=0, Female=1) CD4 cell count(raw lab measurement) y(1:death 0:alive) I perform logistic regression to find out the factors that influence y. result<-glm(y ~ factor(age) + factor(gender) + CD4,family = binomial) >From the result,I can get OR(Odds Ratio) of gender via exp(Estimate of Female,

Hi all: I finished cox analysis like this: fit_cox<-coxph(Surv(dat$Time, dat$death) ~ dat$CD4 + strata(dat$gender),data=dat); > fit_cox Call: coxph(formula = Surv(data_ori$Time, data_ori$death) ~ data_ori$drug + strata(data_ori$gender), data = data_ori) coef exp(coef) se(coef) z p data_ori$drugddI 0.216 1.24 0.146 1.47 0.14 Likelihood ratio test=2.17 on

Hello all: I've read the document named "A Brief Introduction to R, the multilevel package and the nlme package". At p68, one can transform the dataset to the required format by using "make.univ". I wanna know,how the new variable "MULTDV" is calculated(can you show me the formula if possible please?)?And what's the usage of this new variable in the following

Hi all: I've 2 groups of data,which are measured at: 1990,1991,1992,...2000. I wanna know whether the trend of 2 groups are same or not. Maybe time series analysis is suitable,but I don't know which index is fit for my purpose,and how to get the index from function of time series analysis under R environment. Thanks a lot. My best [[alternative HTML version deleted]]

Hi all: As to the "heatmap" function, the default style is "red and yellow",and red refers to low level and yellow refers to high level. How can I change the style to the contrary: red refers to high level and yellow refers to low level? Thanks a lot! My best [[alternative HTML version deleted]]

v1<-c("a","b","c","d") v2<-c("a","b","e") v3<-c("a","f","g") I want to get the intersection of v1,v2,v3,ie "a" How can I do then? What I know is only for 2 vectors via "intersect" function,but don't know how to deal with multiple vectors. Many thanks

Hi all: I have two curve models: model1<-nls(result ~ exp(b0 + b1*(time)), start = list(b0 = 0, b1 = 5),trace=TRUE,data=data1) model2<-nls(result ~ exp(b0 + b1*(time)), start = list(b0 = 0, b1 = 5),trace=TRUE,data=data2) I wanna compare the two models to find out whether the difference between them is significant or not. How can I do then? Many thanks! My best [[alternative

Hi all: Suppose there're 3 groups,and I wanna compare the result of the 3 groups. I've drawn a boxplot.But I wanna show the actural data points of each group at the same time.In other words I wanna combine the boxplot and dotchart together. How can I do it? Thanks a lot! My best. [[alternative HTML version deleted]]

Hi all: I perform the linear mixed model for 300 persons, y is CD4 count,x is time. I randomized slope and intercept,so I can get 300 slopes and 300 intercepts.Now I wanna test wheter the variance of 300 slopes and 300 intercepts differs from zero. If the variance of 300 slopes(or intercepts) differs from zero at 0.05 significant level,I should randomize the slope(or intercept), and if not,I

Hi all: I have a question about the command "followup.plot" of epicale package. As to the demo data "Orthodont", the command "followup.plot" works well.But if I delete some rows of data(delete Male data,and keep Female data only, for instance),the command can't work,and the warning is "In attr(get(search()[2]), "names") ==

As the attachement,I wanna draw multi group plot. But I can only use : plot(x,y...) points(...) It's a heavy work to use these command if there're too many groups to be drawn because I have to use point(....) for many times. I wanna know wheter there's command which can draw the multigroup plot directly? Thanks My best.

Hello sir: I have a question about the axis label of scatterplot3d function. The data is in the attachment. If I use the command: scatterplot3d(x,y,z,type="h") I want the plot's x-axis lab to be 1,2,3,...,13, y-axis lab to be 1,2,3,...11 But if I use the command: scatterplot3d(x,y,z,type="h",x.ticklabs=1:13,y.ticklabs=1:11) The axis labs are overlap, still can't

Hi,all: I have a vector,and wanna get the opposite value via rev function. > a [1] FALSE FALSE TRUE TRUE TRUE > > rev(a) [1] TRUE TRUE TRUE FALSE FALSE > I don't know why the 3rd "TRUE" has not been reversed,while all other values are reversed? Thanks My best [[alternative HTML version deleted]]

Hi all I have a question about "subset" function. > dat id x1 x2 x3 1 a 1 11 111 2 b 2 22 222 3 c 3 33 333 4 d 4 44 444 > subset(dat,id==c("a","c")) id x1 x2 x3 1 a 1 11 111 > subset(dat,id==c("a","d")) id x1 x2 x3 1 a 1 11 111 4 d 4 44 444 >From the above, if I choose id=a,c, the result is wrong,but if I

Hi all: I've got a data of ".bam" which is created from my partner under linux sysyem. My system is window xp, and I wanna know how to read the .bam file. Many thanks! My best [[alternative HTML version deleted]]

Hi all: I am a user of "JM" package. Here's the problem of "sample size". The warning is: Error in jointModel(fitLME, fitSURV_death, timeVar = "time", method = "piecewise-PH-GH") : sample sizes in the longitudinal and event processes differ. According to the suggestion of "missing data",I use the same data set(data_JM) without any