similar to: Probelms on using gam(mgcv)

Displaying 20 results from an estimated 1000 matches similar to: "Probelms on using gam(mgcv)"

2007 Dec 13
1
Two repeated warnings when runing gam(mgcv) to analyze my dataset?
Dear all, I run the GAMs (generalized additive models) in gam(mgcv) using the following codes. m.gam <-gam(mark~s(x)+s(y)+s(lstday2004)+s(ndvi2004)+s(slope)+s(elevation)+disbinary,family=binomial(logit),data=point) And two repeated warnings appeared. Warnings$B!'(B 1: In gam.fit(G, family = G$family, control = control, gamma = gamma, ... : Algorithm did not converge 2: In gam.fit(G,
2007 Dec 12
0
Hep on using GAM() in R
Dear friends, I met some problem on using GAM() function in R. Any help or suggestions are greatly appreciated. # My programs and problems are list below# library(splines) library(gam) point<-read.csv("d:/gam.csv",sep=",",header=TRUE) #read the data gam.opt<-gam(mark~lo(x,y,span=0.2)+lo(lstday2004,span=0.2)+lo(slope,span=0.2)+lo(ndvi2004,span=
2007 Sep 13
2
handle dates in R?
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,
2008 Sep 23
3
Generating series of distributions with the same skewness and different kurtosis or with same kurtosis and different skewness?
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. --
2008 Jan 01
3
Specify a correct formula in R for Piecewise Linear Functions?
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 =
2007 Oct 12
3
Anybody has ever met the problem to add a legend to a figure generated by image()?
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
2007 Oct 02
2
How to add legend for image()?
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
2007 Nov 08
2
question on image() function?
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
2007 Sep 17
2
What's the corresponding function in R for lo() function in S-PLUS?
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:::::::::
2007 Aug 17
3
Is there any good tools to facilitate us to create R functions?
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::::::::: (..):::::::::
2007 Dec 31
2
help on ROC analysis
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 ..................
2007 Jun 01
1
How should i get the quantile 2.5 % and 97.5% in each row of a matrix?
Dear friends, I need the get the 2.5% and 97.5% quantile from each row of a matrix, how should i get it? BTW, i can get the min/max value from each row of a matrix, using the following programs, is there an easy function to do it? simmin<-matrix(NA,nrow=47,ncol=1) for (i in 1:47) { simmin[i,]<-min(datas[i,]) } Thanks for your help. -- With Kind Regards, oooO:::::::::
2007 Aug 25
1
How can i inhibit this work "Please select a CRAN mirror for use in this session "?
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:: ::\_)::(..):: :::::::)./::: ::::::(_/:::: :::::::::::::
2007 Sep 14
1
Calculate the angles for a point dataset?
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
2007 Sep 22
0
How to explain the meaning of mu in the variance function of GLMs?
Dear R friends, When fitting GLMs in R, we may need to specify the variance function to do our analysis. I had thought it's the mean value, but it seems not. Could anybody expain the correct meaning of *mu* in the variance function of GLMs? The following content is from the R-hlep. variance for all families other than quasi, the variance function is determined by the family. The quasi
2007 Sep 23
2
return(x=x,y=y,prob=prob) hasn't been used in R now?
Dear friends, Now, when i use the argument return(x=x,y=y,prob=prob) , R displays the waring message: Warning message: The return value for multiple variables wasn't used in: return(x = x, y = gy, prob = prob) I used the methods of "help.search("return")" and "?return" to get some help, but didn't find info on it. Anybody knows how it should be used
2008 Nov 26
0
Needs suggestions for choosing appropriate R packages
Dear all, I am thinking to fit a multilevel dataset with R. I have found several possible packages for my task, such as glmmPQL(MASS),glmm(repeated),glmer(lme4), et al. I am a little confused by these functions. Could anybody tell me which function/package is the correct one to analyse my dataset? My dataset is as follows: the response variable P is binary variable (the subject is a patient
2007 Jul 09
1
help on fisher.test(stats)?
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)
2008 Dec 06
1
Questions on the results from glmmPQL(MASS)
Dear Rusers, I have used R,S-PLUS and SAS to analyze the sample data "bacteria" in MASS package. Their results are listed below. I have three questions, anybody can give me possible answers? Q1:From the results, we see that R get 'NAs'for AIC,BIC and logLik, while S-PLUS8.0 gave the exact values for them. Why? I had thought that R should give the same results as SPLUS here.
2007 Jul 09
1
a little problem on selecting a subset from dataset A according to dataset B?
Dear Friends, I want to extract the records from A according to B, but the results are not correct because R says : The length of long object is not integer times on the length of short object. Anybody have met the same problem? How to do it correctly? length(A)=47 length(B)=6 A[A$coords.x1==B$X1,] #the program for the above task. I should get 6 records, but i only get former 4 records