similar to: questions on adding reference line?

Dear Rusers, I have some data in .csv file like "2004-8-1" and "2004-10-1", and i need to convert them into days from the origin (January 1, 1960). I have tried the function date.mmddyyyy(), but cannot get it. Anybody can show me how to handle the date data? Thanks very much! My dataset like: time 2004-8-1 2004-10-1 2001-9-1 2002-9-1 -- With Kind Regards,

Dear R users, I hope to explain the concepts of skewness and kurtosis by generating series of distributions with same skewness and different kurtosis or with same kurtosis and different skewness, but it seems that i cannot find the right functions. I have searched the mailing list, but no answers were found. Is it possible to do that in R? Which function could be used? Thanks a lot. --

Dear all, I have two variables, y and x. It seems that the relationship between them is Piecewise Linear Functions. The cutpoint is 20. That is, when x<20, there is a linear relationship between y and x; while x>=20, there is another different linear relationship between them. How can i specify their relationships in R correctly? # glm(y~I(x<20)+I(x>=20),family = binomial, data =

Dear friends, Anybody has ever met the problem to add a legend to a figure generated by image()? I have three variables,x,y and z. x and y are the coordinates, and z is the third values. we can use image(x, y, z,...) to generate a figure according to the z-values, but the problem is the figure legend. How can the legend be added to a figure generated by image()? Note that filled.contour() can

Dear friends, The following is an example to explain my question. I want to get a legend which will show the z-values according to different colors in image() function. x<-sort(runif(10)) #x-coordinates y<-sort(runif(10)) #y-coordinates z<-matrix(runif(100),nrow=10) #attributes values image(x,y,z,col=gray((6:3)/6)) # legend(x,y,legend=z,col=gray((6:3)/6)) #error. the colors should

Dear R users, We have some programs for the specific task in our research, but they were very commonly used. We want to make some functions for them, anybody can recommend any good tools to facilitate us to create R functions even without going deep into the theories of R functions ? Any suggestions or help are greatly appreciated. -- With Kind Regards, oooO::::::::: (..):::::::::

Dear friends, After fitting a generalized linear models ,i hope to get the variance of alpha,variance of beta and their covariance, that is , the variance-covariance matrix/information of alpha and beta , suppose *B* is the object of GLMs, i use attributes(B) to look for the options ,but can't find it, anybody knows how to get it? > attributes(B) $names [1] "coefficients"

Dear friends, In S-PLUS, we can use the following argument, but not in R. mode12 <- gam(score1 ~ lo(latitude) + lo(longitude)) I searched the help in S-PLUS, it says lo() Allows the user to specify a Loess fit in a GAM formula, but i didn't find the correponding function in R. Anybody knows how to do the similar task in R? Thanks very much. -- With Kind Regards, oooO:::::::::

Dear all, Some functions like 'ROC(Epi)' can be used to perform ROC analyssi, but it needs us to specify the fitting model in the argument. Now i have got the predicted p-values (0,1) for the 0/1 response variable using some other approach, see the following example dataset: id mark predict.pvalue 1 1 0.927 2 0 0.928 3 1 0.928 ..................

Dear friends, My dataset is like the following: x y mcpvalue 0.4603578 0.6247629 1.001 0.4603715 0.6247788 1.001 0.4603852 0.6247948 1.001 0.4110561 0.5664841 0.995 The x and y variables are unsorted. I use the function image(x,y,mcpvalue) to generate a plot, but the error is that "increasing 'x' and

Dear all, Following the help from gam(mgcv) help page, i tried to analyze my dataset with all the default arguments. Unfortunately, it can't be run successfully. I list the errors below. #m.gam<-gam(mark~s(x,y)+s(lstday2004)+s(slope)+s(ndvi2004)+s(elevation)+s(disbinary),family=binomial(logit),data=point)

Dear Rusers, I have met a difficult problem on explaining the differences of principal component analysis(PCA) between R,S-PLUS and SAS/STATA/SPSS, which wasn't met before. Althought they have got the same eigenvalues, their coeffiecients were different. First, I list my results from R,S-PLUS and SAS/STATA/SPSS, and then show the original dataset, hoping sb. to try and explain it.

Dear Rusers, My manuscript has been conditionally accepted recently. The problem to generate the high resolution figures in R for the manuscript cannot be solved by me. The journal editor ask me to generate the figures with a minimum resolution of 500 dpi. I have tried the *menu-driven method* to save the figures as JPEG (100% printed quality), but the results seem not to be very good. I have

Dear Ruser, Today, i download R2.4.0-win32.exe, but can't set it up successfully. The error informaiton is : *"0x000038e4"memory quoted by "ox6c7f22b3" can't be "readonly".* My operating system in WindowXP. Where goes wrong? Thanks. -- With Kind Regards, oooO::::::::: (..)::::::::: :\.(:::Oooo:: ::\_)::(..):: :::::::)./::: ::::::(_/:::: :::::::::::::

Dear friends, My dataset have many zeros, so i must use fisher exact test . Unfortunately, the fisher.test(stats) function fail to do it. Anybody knows how to do the fisher exact test with many zeros in the dataset? My dataset is: a<-matrix(c(0,1,0,0,0,0,1,0,1,0,0,0,0,1,0,1,1,0,2,1,5,1,1,6,4,4,1,17,2,8,5,7,1,1,24,3,6,1,1,3,2,16,7,4,0,2,4,0,17,0,1,0,0,0,1,2),nrow=8,byrow=TRUE) data.frame(a)

Dear Uwe Ligges , I still can't finish it. *> aa* #my data x1 x2 y 5 0.05 6 4.4180 1 0.50 3 2.6979 4 0.50 9 2.9000 7 0.95 6 2.6230 8 0.95 6 2.9078 9 0.95 6 2.6727 3 1.40 3 2.4203 2 1.40 9 2.5329 6 1.85 6 2.4867 *> attach(aa)* *> persp(x1,x2,y* error in persp.default(x1, x2, y) : increasing 'x' and 'y' values expected

Dear Rusers, I want to know which function in R can perform the following tasks: 1.surface-data grid(x,y,z) #which could be done in splus, the name was from splus's options of graph 2. contourplot(x,y,z) #which could be done in splus By the way, where can i find some useful materials to learn to plot 3-dimensionel graphs? Thanks! -- With Kind Regards, oooO::::::::: (..):::::::::

Dear Rusers, When i start R, there always the following work to do first, how should i cancel it? *--- Please select a CRAN mirror for use in this session ---* I don't know why it does so, maybe i have done something unintentionally. Thanks. -- With Kind Regards, oooO::::::::: (..)::::::::: :\.(:::Oooo:: ::\_)::(..):: :::::::)./::: ::::::(_/:::: :::::::::::::

Dear Rusers, I'd like to take the cases of cancer of the larynx in chorley(spatstat) to explain my question. I want to join the points of cancer of the larynx with the disused industrial incinerator to generate lines, and then calculate the angles of these line comparing the horizontal line? How can i get it? It seems to be difficult to get the angles Thanks a lot. -- With Kind

Dear friends, When i read the R-help , i often find the following case: e.g.:surf.gls(np, covmod, x, y, z, nx = 1000, ...) #Package Spatial: Arguments: covmod: function to evaluate covariance or correlation function * ...: parameters for 'covmod'* How should i find the further information on "*...: parameters for 'covmod'*" ? I use the ?covmod, but