similar to: An exercise in the use of 'substitute'

Hi, I tried to do a multiple linear model from the example dataset Formaldehyde. However, the function lm() did not estimate the coefficient of the term carb^2. The same problem occurred with the (nlme)dataset Pixel with both function lme() and lm(). I am using the windows version of R 1.5.1 Lauri Mehtatalo The Formaldehyde example: > data(Formaldehyde) >

Hi, I use lm or loess to make smoothing. After smoothing I need "Residual Standard Error" in my script. Could you please tell me how can I get this information? Thanks,

The editor in R version 1.2.0 returns an error after editing a data frame that has row names. This is on a Windows 2000 system, but I've encountered the same problem under Windows 95. Here's a simple example: ------------------------------------------------------------------------------------ R : Copyright 2000, The R Development Core Team Version 1.2.0 (2000-12-15) R is free

On Sun, 31 Dec 2000 jfox@mcmaster.ca wrote: > The editor in R version 1.2.0 returns an error after editing a data frame > that has row names. This is on a Windows 2000 system, but I've encountered > the same problem under Windows 95. Here's a simple example: Actually, that's not where the error is. If you use traceback() you will see it is in edit.data.frame. That tries

I am encountering difficulty with NextMethod in 0.50-a4. We created a class of groupedData objects which are data.frames with additional attributes. The most important attribute is a formula describing roles of some of the variables in the experimental design. The class of such objects ends in "groupedData", "data.frame". The print method for the groupedData class simply

Hello R users, I have been looking through Help files and Nabble list for the answers for these simple questions, but it seems to be fruitless. 1- in a data frame with two columns, x and y, how do I get the corresponding value of x to, let's say, the minimum value of the y column (min (data$y)) ? 2- how do I solve a simple equation? Considering the equation y= exp(-x)^12, I would like to find

Greetings. Is there any way to get R to take a regression model object and draw a plot of the regression function? How about overlaying that plot over a scatterplot of the actual data? Thanks in advance for any help anyone can provide. Aaron ----- Aaron Solomon?? (??ben Saul Joseph??) ??Adelman E-mail??: ??adelmaas at musc.edu Web site??: ??http??://??people.musc.edu??/??~adelmaas??/??

At present the example data sets in R libraries are to be given as expressions that can be read directly into R. For example, the acid.R file in the main library looks like acid <- data.frame( carb = c(0.1, 0.3, 0.5, 0.6, 0.7, 0.9), optden = c(0.086, 0.269, 0.446, 0.538, 0.626, 0.782), row.names = paste(1:6)) This is great when you have only a few observations. I have one example data

Dear everybody: We used the fine foreign library to bring in an SPSS dataset that was about 9 megabytes and I can squeeze it into a much smaller R object using compression with save(ndat, file="NatAnnES2000.rda", compress=T). I can use load() to get the "ndat" dataframe back, that's all good as far as I can see. If I put that file in the data subdirectory, then the

Should the F statistic be the same when using add1() on models created by lm and glm(family=gaussian)? They are in the single-degree-of-freedom case but not in the multiple-degree-of-freedom case. MASS:addterm shows the same discrepancy. It looks like the deviance (==residual sum of squares) gets divided by the number of degrees of freedom for the term twice in add1.glm. Using anova() on the

I have applied the same linear model to several different subsets of a dataset. I recently read that in R, code should never be repeated. I feel my code as it currently stands has a lot of repetition, which could be condensed into fewer lines. I will use the mtcars dataset to replicate what I have done. My question is: how can I use fewer lines of code (for example using a for loop, a function or

Hi, Hope you are well. I was wondering if there is a function at C level that is equivalent to mtcars$carb or .subset2(mtcars, "carb"). If I have the index of the column then the answer would be VECTOR_ELT(df, asInteger(idx)) but I was wondering if there is a way to do it directly from the name of the column without having to loop over columns names to find the index? Thank you Best

I think you are not using the best function for what your intentions are. Try: > by(data=mtcars, INDICES=list(as.factor(mtcars$am)), FUN=colMeans) : 0 mpg cyl disp hp drat wt qsec vs 17.1473684 6.9473684 290.3789474 160.2631579 3.2863158 3.7688947 18.1831579 0.3684211 am gear carb 0.0000000

Dear all I'm unable to find an example of extracting the rotated scores of a principal components analysis. I can do this easily for the un-rotated version. data(mtcars) .PC <- princomp(~am+carb+cyl+disp+drat+gear+hp+mpg, cor=TRUE, data=mtcars) unclass(loadings(.PC)) # component loadings summary(.PC) # proportions of variance mtcars$PC1 <- .PC$scores[,1] # extract un-rotated scores of

Hola, Bueno, puedes hacer el cálculo de una forma mucho más compacta y rápida. Esta forma es especialmente recomendable cuando tienes muchas columnas y muchas filas. > library(data.table) > myDT <- as.data.table(mtcars) > myDTlong <- melt(myDT, measure.vars=1:ncol(myDT)) > myDTlong[ , list(p_value = shapiro.test(value)$p.value, v_stat = shapiro.test(value)$statistic) , by

Hi everyone, I've run into a bit of strange problem with implicit vs explicit printing and the call stack. I've included an example at the bottom of this email. The basic problem is that I have an S3 object with a print method. When the object is implicitly printed (ie. typed directly into the console) the function arguments in the call stack are exploded out to their actual values,

Dear All, Thanks for your help. However, I would like to draw your attention to the following: Actually, I was replicating the Example 2.3, using the dataset "brainsize.txt" given in Section 2.3.3 ("Summarize by group") at page 55, of a famous book "R by Example" written by "Jim Albert and Maria Rizzo" published in Springers (2012) in a Use R! Series. The

> On Apr 15, 2016, at 1:16 AM, Akhilesh Singh <akhileshsingh.igkv at gmail.com> wrote: > > Dear All, > > Thanks for your help. However, I would like to draw your attention to the > following: > > Actually, I was replicating the Example 2.3, using the dataset > "brainsize.txt" given in Section 2.3.3 ("Summarize by group") at page 55, > of a

Dear Sirs, I am Professor at Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh, India. While taking classes, I found the *by() *function producing following error when I use FUN=mean or median and some other functions, however, FUN=summary works. Given below is the output of the example I used on a built-in dataset "mtcars", along with error message reproduced herewith: >

can you recommend a good manual for R that starts with a data set and gives demonstrations on what can be done using R? I downloadedR Langauage definition and An introduction to R but haven't found them overly useful. I'd really like to be able to follow some tutorials using a dataset or many datasets. The datasets I have available on R are Data sets in package 'datasets':