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...riables: > >x<-sample(LETTERS[1:3],20,TRUE) >y<-sample(LETTERS[24:26],20,TRUE) >mosaicplot(table(x,y)) > >If you could tell us how the above is not what you want, perhaps a >better suggestion will appear. > >Jim > > >On Sat, Feb 7, 2015 at 6:29 PM, meng <laomeng_3 at 163.com> wrote: >> If both x and y are all character, paired scatter plot is a little bit strange I think. >> >> >> >> >> >> >> -- >> QQ: 1733768559 >> >> >> >> >> >> At 2015-02-06 23:52:34,"Duncan...

hi all: Here's a dataframe(dat) and a vector(z): dat: x1 x2 x3 0.2 1.2 2.5 0.5 2 5 0.8 3 6.2 > z [1] 10 100 100 I wanna do the following: 10*x1,100*x2,1000*x3 My solution is using the loop for z and dat(since the length of z is the same as ncol of dat),which is tedious. I wanna an efficient solution to do it . Any help? Many thanks! My best

Hi,all: I met a problem of nls. My data: x y 60 0.8 80 6.5 100 20.5 120 45.9 I want to fit exp curve of data. My code: > nls(y ~ exp(a + b*x)+d,start=list(a=0,b=0,d=1)) Error in nlsModel(formula, mf, start, wts) : singular gradient matrix at initial parameter estimates I can't find out the reason for the error. Any suggesions are welcome. Many thanks. [[alternative HTML

Hi all: My data is in the attachment. I want to analysis the mean difference of y between 2 sex. My code: result_lm<-lm(y~factor(sex) + x1 + x2) summary(result_lm) The result of "factor(sex)m" 136.83, is the mean difference of y between 2 sex,and the corresponding p value is 0.07618. My question is: how to get the mean y of sex(m) and sex(f) respectively via lm function? Many

Hi,all: I want to perform multiple correspondance analysis via MCA{FactoMineR}. The data is in the attachment. My code: dat<-read.delim("e:\\mydata.txt",header=T) MCA(dat,quanti.sup=7,quali.sup=1:6) Error in `[.data.frame`(tab, , i) : undefined columns selected My question: Why does the error happen? Many thanks. Best. -------------- next part -------------- An embedded and

A data set(dat),has 2 variables: x and a, and 100 rows. I wanna add 2 variables,and call the new data set dat1: var1:f = a/median(a) var2:x_new = x*f My solution: dat1<-transform(dat,f = a/median(a),x_new = x*f) But gets error reply which says that "f" is not exits since dat has no variables called "f". So I have to do through 2 steps:

Hi all: If there are two numeric variable:x,y, and I can get paired scatter plot by function "pairs".But if x and y are character, and I want to get paired mosaic plot,which function should be used then? Many thanks! My best. -- QQ: 1733768559 [[alternative HTML version deleted]]

Hi all: I have a quesion about ANOVA: Is SS(Sum of Square) of a specific factor constant with the number of factors changing? dat1 includes one factor g1,and g1's SS is called SS_g1_dat1. dat2 includes two factors g1,g2,and g1's SS is called SS_g1_dat2. My quesion is: Is SS_g1_dat1 equals to SS_g1_dat2? I have both "yes" and "no" reasons for the quesion,but

Hi all: I have a question about multi-comparison. The data is in the attachment. My purpose: Compare the predicted means of the 3 methods(a,b,c) pairwisely. I have 3 ideas: #idea1 result_aov<-aov(y~ method + x1 + x2) TukeyHSD(result_aov) diff lwr upr p adj b-a 0.845 0.5861098 1.1038902 0.0000001 c-a 0.790 0.5311098 1.0488902 0.0000002 c-b -0.055 -0.3138902

Hi all: I have a question about the computation of expression: y = 1+(2x1+2)-3*(5x1-1)+(3x2+3)-2*(x2-1) The result of y is: y = 11-13x1+x2 How can I compute the result of y via R function? Many thanks! My best. [[alternative HTML version deleted]]

Hi all: I met a question about plotting the predict values of time series. The data is treering which belongs to R. I want to predict the next 3 years(1980,1981,1982) result. pred<-predict(ar(treering),n.ahead=3) plot(treering) lines(pred$pred,col="red",lwd=3) I can only find a little bit red point at the end of the plot,but can't see it clearly. Maybe I should

Hi all: For stratified count data,how to perform regression analysis? My data: age case oc count 1 1 1 21 1 1 2 26 1 2 1 17 1 2 2 59 2 1 1 18 2 1 2 88 2 2 1 7 2 2 2 95 age: 1:<40y 2:>40y case: 1:patient 2:health oc: 1:use drug 2:not use drug My purpose: Anaysis whether case and