Displaying 20 results from an estimated 900 matches similar to: "lm type of sums of squares"
2009 Jun 15
1
altering a global variable
I'm working on a program that loads several large data files. I'm
using ddply (plyr is really awesome) but I want to minimize the amount
of times a large data file is read in. One solution is to keep track
of which data file is open with a global variable and then change the
currently open data file globally as needed. However, I'm unclear on
how to alter a global variable
2010 Feb 16
1
suppress printing within a function
I'm working with a few functions (e.g. do.base.descriptions in the
netstat package) that, in addition to returning an object with
variables I want to extract, also print output. There is no way to
turn this default printing behavior off in many of the functions.
Is there a blanket way to suppress such printing, say, within a loop
or a ddply statement?
Thanks!
-Jarrett
2008 May 06
1
question about se of predicted glm values
Hey, all. I had a quick question about fitting new glm values and
then looking at the error around them. I'm working with a glm using a
Gamma distribution and a log link with two types of treatments.
However, when I then look at the predicted values for each category, I
find for the one that is close to 0, the error (using se.fit=T with
predicted) actually makes it overlap 0.
2005 Nov 15
1
Repeates Measures MANOVA for Time*Treatment Interactions
Dear R folk,
First off I want to thank those of you who responded with comments for
my R quick and dirty stats tutorial. They've been quite helpful, and
I'm in the process of revising them. When it comes to repeated
measures MANOVA, I'm in a bit of a bind, however. I'm beginning to see
that all of the documentation is written for psychologists, who have a
slightly
2008 Apr 15
2
glht with a glm using a Gamma distribution
Quick question about the usage of glht. I'm working with a data set
from an experiment where the response is bounded at 0 whose variance
increases with the mean, and is continuous. A Gamma error
distribution with a log link seemed like the logical choice, and so
I've modeled it as such.
However, when I use glht to look for differences between groups, I get
significant
2008 Feb 04
1
extracting AIC scores from lmer and other objects
I have a slight conundrum. I'm attempting to write a scrip that will
take a number of objects (lm, glm, and lmer) and return AIC scores
and weights. I've run into 3 problems, and was wondering if anyone
had any pointers.
1) is there any convenient way to extract the name of the objects?
Simply, if I have a vector of objects c(my.lm, my.lmer) and I want to
get a character
2005 Oct 22
0
Getting univariate information from a multivariate data set
A quick question that I've had only partial success in answering. I
have a multivariate dataset, and would like to extract some simple
univariate information from it grouped by treatments, etc. I am
encountering two problems however
Note: I am importing my data with
my_data <- read.csv("/path/data.csv")
1) Scoping of unstack
If I attempt
sorted_data <- unstack(response,
2006 Feb 28
0
Canonical Values and Centroids for MANOVA plots
Hey, all, I'm trying to construct a centroid plot using canonical
values from a MANOVA. I know that from the summary.manova object you
can get Eigenvalues, and the H and E matrices (from SS$Treatment and
SS$Residuals), but I am at a loss to get the loadings for the canonical
values, nor values for the centroid centers and radii. Is there a
package that does this that I am just missing,
2005 Nov 01
1
R Graphs in Powerpoint
I've tried several methods in OS X, and here's what works best for me. Save the R graphic as a PDF file. Open it with Apple's "Preview" application, and save it as a PNG file. The resulting .png file can be inserted into MS Word or PowerPoint, can be resized, and looks good on either OS X or Windows. There are other programs available for translating the pdf file to png
2005 Nov 08
2
A Quick and (Very) Dirty Intro to Stats in R
Greetings to all,
First off, I want to thank you all for answering any nagging questions
I've had over the past few days. I've been in the process of putting
together A Quick and (Very) Dirty Intro to Doing Your Statistics in R
(which I have posted to http://didemnid.ucdavis.edu/rtutorial.html ) in
order to teach an R workshop for the graduate students in my
department. This is a
2005 Nov 08
1
Type II and III sums of squares with Error in AOV
I've recently run into the problem of using aov with nested factors,
and wanting to get the type II and III sums of squares. Normally Anova
from the car package would do fine, but it doesn't like having an Error
included, so
my.aov <-aov(Response ~ Treatment + Error(Treatment:Replicate))
Anova(my.aov, type="II")
yields
Error in Anova(nested.anova) : no applicable method
2011 Nov 07
0
new version 2.0-0 of the sem package
Dear R users,
Jarrett Byrnes and I would like to announce version 2.0-0 of the sem package
for fitting observed- and latent-variable structural equation models. This
is a general reworking of the original sem package (which is still available
on R-Forge as package sem1).
Some highlights of sem 2.0-0 include:
o More convenient and compact model specification, including the default
automatic
2011 Nov 07
0
new version 2.0-0 of the sem package
Dear R users,
Jarrett Byrnes and I would like to announce version 2.0-0 of the sem package
for fitting observed- and latent-variable structural equation models. This
is a general reworking of the original sem package (which is still available
on R-Forge as package sem1).
Some highlights of sem 2.0-0 include:
o More convenient and compact model specification, including the default
automatic
2012 Apr 15
0
version 3.0-0 of the sem now on CRAN
Dear R users,
Version 3.0-0 of the sem package is now on CRAN. From the package NEWS file:
o Compiled code for optimization.
o Added multi-group models.
o Modification indices for equality-constrained parameters.
o weights argument added to tsls().
o raw argument added to cfa().
Of these changes, the first two are the most significant, and the first --
the use of compiled code to
2005 Oct 25
1
Ryan's Q Post-Hoc for ANOVA
I'm using lm to run an ANOVA, and would like to use Ryan's Q as my
post-hoc (as recommended by Day and Quinn, 1989, Ecological
Monographs). I can't seem to find any methods in the base stats
package that implement this post-hoc. Is there a good package of
post-hoc methods out there, or has someone written a method for Ryan's
Q previously?
Thanks!
-Jarrett
2005 Nov 08
2
Simple Nesting question/Odd error message
I'm attempting to analyze some survey data comparing multiple docks. I
surveyed all of the slips within each dock, but as slips are nested
within docks, getting multiple samples per slip, and don't really
represent any meaningful gradient, slip is a random effect. There are
also an unequal number of slips at each dock.
I'm having syntactical issues, however. When I try
2007 Feb 13
4
Advice on visual graph packages
Hey, all. I'm looking for packages that are good at two things
1) Drawing directed graphs (i.e nodes and edges), both with single
and double headed arrows, as well as allowing for differences in line
width and solid versus dashed. Note: I've tried Rgraphviz here, but
have run into some problems (which seem fixable and I may go with it
in the end), and it doesn't satisfy need
2010 Aug 11
2
a question regarding updating formulas with coefficients
I have formulae with coefficents that I would like to update. However, I get some strange results. For example, see the following:
For the formula y ~ d+ 3*r+t I want to add a variable p, so
> update(y~d+0*r+t, .~.+p)
produces
y ~ d + t + p - 1
If the coefficient is not 0, but rather, something else - say, 3, I get the following:
> update(y~d+3*r+t, .~.+p)
Error in
2006 Sep 13
1
Updating lmer - object is not subsettable?
I'm attempting to write a general function to implement Faraway's
bootstrapping algorithm for mixed models with lmer, but have run into
a curious problem. I'm comparing two models
model.1<-lmer(Response ~ Treatment + (1|Trial), data=exp.data,
method="ML")
model.2<-lmer(Response ~ 1 + (1|Trial), data=exp.data, method="ML")
When I attempt to update
2009 Apr 29
1
Hierarchical Diagram of Networks in sna or otherwise?
I've been using sna to work with some networks, and am trying to visualize
them easily. My networks are hierarchical (food webs). All of the layout
engines I've tried with gplot don't seem to plot hierarchical networks, as
one would using dot from graphviz. While I could do all of this by
outputting to dotfiles and running it through graphviz, the graphics I get
from R are much