similar to: regression constraints?

gday gurus, could someone please help me with this one? Can't find it in the doco. summary of my lm object gives "Pr(>|t|)" but coef doesn't. How do I get hold of these probabilities within an object? There doesn't seem to be an appropriate attribute within the object - I was hoping for something like "my.lm$probabilies". I was hoping to grab the best t

Dear List-members, Hopefully someone will help through my confusion: In order to get the same coefficients as we get from the following ## require (MASS) summary ( lm(Gas ~ Insul/Temp - 1, data = whiteside) ) ...................... we need to do the following (if we use model.matrix to specify the model) ## summary ( lm(Gas ~ model.matrix(~ Insul/Temp - 1) - 1, data = whiteside) )

gday R friends, I was wondering if anyone could help me with some graphics issues please. I'm processing R in batch on redhat6.2 with some graphics to be imported into msword on NT. For scaling within my doco I want some vector type graphics. win.metafile doesn't seem to be supported on redhat which gives me postscript. postscript is ideal but doesn't contain a preview so I

Thanks to Brian Ripley for the time and effort put into developing the factanal package for R. I have found it very useful. However, in trying to replicate some results from previous research, I have run into the need for a couple of extensions and was wondering if they might find their way into future implementations. 1. Though maximum likelihood estimates might be more rigorous and

Hi, How would one go about determining if the slope terms from an analysis of covariance model are different from eachother? Based on the example from MASS: library(MASS) # parallel slope model l.para <- lm(Temp ~ Gas + Insul, data=whiteside) # multiple slope model l.mult <- lm(Temp ~ Insul/Gas -1, data=whiteside) # compare nested models: anova(l.para, l.mult) Analysis of Variance

A pragmatic solution could be to create a simple linear regression example with variables in the global environment and then another example with a data.frame. The latter might be somewhat more complex, e.g., with several regressors and/or mixed categorical and numeric covariates to illustrate how regression and analysis of (co-)variance can be combined. I like to use MASS's whiteside

gday R friends, Since I had random errors with ghostscript 6.01 I thought I'd upgrade. After upgrading to gs6.5 I've had problems. Originally, gs failed complaining about lack of "__sysconf" in glibc2.2 so I upgraded glibc. Now I get this. Note that it used to work with gs6.01. I realise this is probably a ghostscript problem but you never know... thanks, John Strumila >

Page 140 of MASS uses the function xyplot. But I don't find it in R. Is there a package that I should load to use xyplot. Or there is a function with a different name in R that does the same thing as xyplot in S. xyplot(Gas ~ Temp | Insul, whiteside, panel = function(x, y, ...) { panel.xyplot(x, y, ...) panel.lmline(x, y, ...) }, xlab = "Average external temperature (deg. C)", ylab

gday R gurus, has anyone seen this lm problem? When I add 2 bytes to the variable name (via names), lm returns an error. It's as if there's a limit to the size of the variable names. Any suggestions? thanks, John Strumila > names(y)[12:14] [1] "Log.SQLServer.Locks.RID.Lock.Wait" "Log.SQLServer.Lock" [3] "xxaa"

G'day R friends, I didn't get any replies on the main list so I thought I'd try with the experts. I was wondering if anyone's ported R to os390. If so, are the vsize and nsize limits the same as other platforms? I could really annoy those SAS guys then. thanks, John Strumila john.strumila@team.telstra.com

R-helpers; I tried to get a superscripted 3 in the following xyplot example but failed: >data(whiteside) >xyplot(Gas ~ Temp | Insul, whiteside, panel = function(x, y, ...) { panel.xyplot(x, y, ...) panel.lmline(x, y, ...) }, xlab = "Average external temperature (deg. C)", ylab = paste(paste("Gas consumption (1000", expression(ft^3),")"), aspect

so i am having this question what should i do if the give data file (.txt) has 4 columns, but different lengths? how can i read them in R? any idea for the following problem? Gas consumption (1000 cubic feet) was measured before and after insulation was put into a house. We are interested in looking at the effect of insulation on gas consumption. The average outside temperature (degrees celcius)

gday R gurus, I've never attempted to use download.file before on my win2k machine but this version 1.4 looks exciting. However, I'm not getting something right. I've passed my R shortcut --internet2 and I can tell it's using the wininet calls because it's asking about authentication but how do I tell it my username/password? The help file only talks about user/pw for non

In "Modern Applied Statistics with S-Plus" 3rd ed., footnote on page 153 regarding a model lm(Gas~Insul/(Temp+I(Temp^2))-1,whiteside), I read "Notice that when the quadratic terms are present, first degree coefficients mean 'the slope of the curve at temperature zero', so a non-significant value does not mean that the linear term is not needed.

On Sat, 15 Dec 2018, frederik at ofb.net wrote: > I agree with Steve and Achim that we should keep some examples with no > data frame. That's Objectively Simpler, whether or not it leads to > clutter in the wrong hands. As Steve points out, we have attach() > which is an excellent language feature - not to mention with(). Just for the record: Personally, I wouldn't recommend

g'day R friends, can anyone please help me with a frustrating merge? The number of rows of a resulting merge is the smaller of the 2 dataframes used as input. What am I doing wrong? I'm using 1.1.0 on redhat 6.2 thanks, John Strumila > xx[1:10,] datetime c 948992940 948992940 0 948993000 948993000 0 948993060 948993060 0 948993120 948993120 0 948993180 948993180 0

R folks, As an R novice, I struggle with the mystery of subsetting. Textbook and online examples of this seem quite straightforward yet I cannot get my mind around it. For practice, I'm using the code in MASS Ch. 6, "whiteside data" to analyze a different data set with similar variables and structure. Here is my data frame: ###subset one of three cases for the variable

Dear All, I would like to minimise a nonlinear function subject to linear inequality constraints as part of an R program. I have been using the constrOptim function. I have tried all of the methods that come with Optim, but nothing finds the correct solution. If I use the correct solution as the vector of starting values, though, my program does output the correct solution and optimum - the

Dear list, I am trying to follow an example that estimates a 2x2 markov transition matrix across several periods from aggregate data using restricted least squares. I seem to be making headway using solve.QP(quadprog) as the unrestricted solution matches the example I am following, and I can specify simple equality and inequality constraints. However, I cannot correctly specify a constraint

Dear guRus, I am doing a logistic regression using restricted cubic splines via rcs(). However, the fitted probabilities should be nondecreasing with increasing predictor. Example: predictor <- seq(1,20) y <- c(rep(0,9),rep(1,10),0) model <- glm(y~rcs(predictor,n.knots=3),family="binomial") print(1/(1+exp(-predict(model)))) The last expression should be a nondecreasing