similar to: Should there be a confint.mlm ?

Displaying 20 results from an estimated 300 matches similar to: "Should there be a confint.mlm ?"

2018 Jul 20
0
Should there be a confint.mlm ?
>>>>> steven pav >>>>> on Thu, 19 Jul 2018 21:51:07 -0700 writes: > It seems that confint.default returns an empty data.frame > for objects of class mlm. For example: > It seems that confint.default returns an empty data.frame for objects of > class mlm. Not quite: Note that 'mlm' objects are also 'lm' objects, and so it is
2008 Aug 22
2
WinBUGS with R
Dear Users, I am new to both of things, so do not blame me too much... I am busy with semiparametric regression and use WinBUGS to sample posteriors. The code to call Winbugs is as follows: data <- list("y","X","n","m") #My variables inits.beta <- rep(0,K) inits.beta0 <- 0 inits <-
2011 Mar 23
1
how to add in interaction terms in gamm
I want to use gamm to generate smoothed trend line for three groups identified by dummy variable genea and geneb. My question is how to add in an interaction term between the time and another dummy variable such as gender? fitm<-gamm(change_gfr~ genea+geneb+s(timea_n,bs="ps")+s(timeb_n,bs="ps")+s(timec_n,bs="ps"),data=mm,random=list(time_n=~1|PID)) -- View this
2011 Aug 02
1
update.default: fall back on model.frame in case that the data frame is not in the parent environment
Dear all, Suppose the following code: --------------8<-------------- mm <- function(datf) { lm(y ~ x, data = datf) } mydatf <- data.frame(x = rep(1:2, 10), y = rnorm(20, rep(1:2, 10))) l <- mm(mydatf) -------------->8-------------- If I want to update l now without providing the data argument an error occurs: --------------8<-------------- > update(l, . ~ .) Error in
2012 Mar 20
1
overriding "summary.default" or "summary.data.frame". How?
I suppose everybody who makes a package for the first time thinks "I can change anything!" and then runs into this same question. Has anybody written out information on how a package can override functions in R base in the R 2.14 (mandatory NAMESPACE era)? Suppose I want to alphabetize variables in a summary.data.frame, or return the standard deviation with the mean in summary output.
2011 Nov 03
1
Select columns of a data.frame by name OR index in a function
Dear all, Sometimes I have the situation where a function takes a data.frame and an additional argument describing come columns. For greater flexibility I want to allow for either column names or column indices. What I usually do then is something like the following: -------------8<------------- f <- function(datf, cols) { nc <- seq_along(datf) cn <- colnames(datf) colOK <-
2011 Oct 26
2
Error in summary.mlm: formula not subsettable
When I fit a multivariate linear model, and the formula is defined outside the call to lm(), the method summary.mlm() fails. This works well: > y <- matrix(rnorm(20),nrow=10) > x <- matrix(rnorm(10)) > mod1 <- lm(y~x) > summary(mod1) ... But this does not: > f <- y~x > mod2 <- lm(f) > summary(mod2) Error en object$call$formula[[2L]] <- object$terms[[2L]]
2003 Sep 19
1
predict for mlm does not work properly
Hello, I've just fitted a model with multi-responses, and I get an object of class "lm" "mlm". My problem is that as soon as I invoke the predict method for a dataframe "newdata", the methods runs and give me back prediction at the fitting points but not for newdata. Does someone has an explanation for this behavior, and some ideas to make predict.mlm work
2010 Apr 16
1
Multiple comparisons on Anova.mlm object
I would like to perform multiple comparisons or post-hoc testing on the independent variable in an Anova.mlm object generated by the Anova function of the car package. I have defined a multivariate linear model and subsequently performed a repeated measures ANOVA as per the instructions in section #3 of the following comprehensive tutorial on the subject from the Gribble lab at UWO:
2009 Jan 30
3
Q about how to use Anova.mlm
Hi, Am newish to stats and R, so I certainly appreciate any help. Basically I have 50 inidividuals whom I have 6 photos each of their optic nerve head. I want to check that the orientation of the nerve head is consistent, ie the 6 replicates show minimal or preferably no rotation differences. I'll draw an arbitrary line between some blood vessels (same reference in each set of replicates) and
2012 Feb 08
2
dropterm in MANOVA for MLM objects
Dear R fans, I have got a difficult sounding problem. For fitting a linear model using continuous response and then for re-fitting the model after excluding every single variable, the following functions can be used. library(MASS) model = lm(perf ~ syct + mmin + mmax + cach + chmin + chmax, data = cpus) dropterm(model, test = "F") But I am not sure whether any similar functions is
2002 Jun 25
2
predict.mlm bug?
I believe there is a coding error in the first part of predict.mlm in the splines package, but perhaps someone could explain the logic to me if I'm wrong. I don't see how the second if (missing(newdata)) could ever be true. (I would show the code but I'm using email on a different machine than R today.) Paul Gilbert
2006 Mar 13
1
anova.mlm (single-model case) does not handle factors? (PR#8679)
Full_Name: Yves Rosseel Version: 2.2.1 OS: i686-pc-linux-gnu Submission from: (NULL) (157.193.116.152) Dear developers, For the single-model case, the anova.mlm() function does not seem to handle multi-parameter predictors (eg factors) correctly. A toy example illustrates the problem: Y <- cbind(rnorm(100),rnorm(100),rnorm(100)) A <- factor(rep(c(1,2,3,4), each=25)) fit <- lm(Y ~ A)
2008 May 30
1
robust mlm in R?
I'm looking for something in R to fit a multivariate linear model robustly, using an M-estimator or any of the myriad of other robust methods for linear models implemented in robustbase or methods based on MCD or MVE covariance estimation (package rrcov). E.g., one can fit an mlm for the iris data as: iris.mod <- lm(cbind(Sepal.Length, Sepal.Width, Petal.Length, Petal.Width) ~ Species,
2004 Feb 25
1
structure of mlm objects ?
Hello, I am using the function "lm" to fit several responses at the same time (100 responses). At the end of the fit, I get an object of class "mlm". I would like to know if there is a way to access to each of the 100 underlying models separately (is it a list, ... ?). Which syntax should I use to see and use the 15th model (for instance) just like it is possible for classical
2005 Jun 15
1
Anohter anova.mlm problem
Hi, yet another anova.mlm problem - it doesn't seem to end. This time, I have a setup with a few within-subject factors and a between-subject factor (SGROUP). Consider the most simple case with only one within-factor (apo): > mlmfit0 <- lm(data.n ~ 0 + SGROUP) > mlmfit1 <- lm(data.n ~ 1 + SGROUP) > anova(mlmfit1,mlmfit0,test="Spherical",M=~hemi,X=~1) Analysis of
2008 Sep 09
1
How do I compute interactions with anova.mlm ?
Hi, I wish to compute multivariate test statistics for a within-subjects repeated measures design with anova.mlm. This works great if I only have two factors, but I don't know how to compute interactions with more than two factors. I suspect, I have to create a new "grouping" factor and then test with this factor to get these interactions (as it is hinted in R News 2007/2), but
2006 Nov 21
4
means over factors in mlm terms
I'm trying to write a function to find the means over factors of the responses in a mlm (something I would do easily in SAS with PROC SUMMARY). The not-working stub of a function to do what I want is below, and my problem is that I don't know how to call aggregate (or some other function) in the context of terms in a linear model extracted from a lm/mlm object. means.mlm <-
2001 Aug 12
0
predict.mlm: Error: Object "X" not found (PR#1049)
predict.mlm fails with the error: Object "X" not found. CAUSE: looking at the predict.mlm function, we have: x <- model.matrix(object, newdata) two lines later, we have: pred <- X[, piv, drop=FALSE] %*% object$coefficients[piv,] SOLUTION(?): change the case of one of the x's, since it seems like what is meant in the second line is lowercase x... platform:
2005 Jun 01
0
anova.mlm again
[hope this doesn't get posted twice, my first mail bounced] Hi, again, this is about the call bug in anova.mlm. I originally reported it as PR#7898 and I suggested a fix at PR#7904. (None of these message were forwarded to R-Devel, instead I received a bounce telling me that my provider's SPF settings are incorrect. They are, though, so there seems to be a problem with the