Displaying 20 results from an estimated 11000 matches similar to: "Type III Sums of Squares"
2002 Mar 01
4
Type III Sum of Squares
Hi,
When doing a two-ways anova in R and comparing my same results with an SPSS
output, I noticed that R calculated type I Sum of Squares. Is it possible to
use Type III Sum of Squares?
Thanks,
S?bastien Plante
Institut des Sciences de la Mer de Rimouski (ISMER)
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read
2002 Apr 29
2
Lotos 1-2-3 date to POSIXct
I have some data that was created for import into a Lotus 1-2-3 spreadsheet
and on of the columns is time. The
time is akin to Julian were the value 1 is mapped "01-Jan-00 12:00:00 AM" in
Lotus 1-2-3. Is there a function in an R package that can convert this
numeric vector to a POSIXct vector?
With best wishes and kind regards I am
Sincerely,
Corey A. Moffet
Instructor
Department
2002 Jan 10
4
Test if beta is different from something other than 0
Is there a function/package that will allow you to test the hypothesis beta1
= x in a
simple linear regression, where x is a constant? The AOV tests if beta1 in
different from
0 but what if I want to know if beta1 one is different from 1?
With best wishes and kind regards I am
Sincerely,
Corey A. Moffet
Instructor
Department of Range, Wildlife, and Fisheries Management
Mail Stop 2125
Texas
2002 Apr 17
4
Problem w/ axis and distortion in a plotting function
I have a function for plotting soil texture that I am having a problem with.
The function is:
plot.psd <- function(sand, clay, ...) {
conv.ter <- function(x, y) {
x.con <- 100 - x - y*cos(1/3*pi)
y.con <- y*sin(1/3*pi)
data.frame(x=x.con, y=y.con)
}
plot(conv.ter(sand, clay), xlim = c(0,100), ylim = c(0,100*sin(1/3*pi)),
axes = FALSE, xlab="",
2000 May 09
1
Type III Sums of Squares?
Hello,
I'd like to propose an extension to the function summary.aov.
In Splus (2000, I don't know about other versions), summary.aov allows a
parameter ssType to be set to 1 or 3 (defaults to 1) to choose the type of
Sums of Squares.
I know I can get Type III SS in R with drop1(model), but including the
functionality into summary.aov would, in my opinion,
- yield a more usable table
2010 Jun 03
3
Nested ANOVA with covariate using Type III sums of squares
Hello,
I have been trying to get an ANOVA table for a linear model containing a
single nested factor, two fixed factors and a covariate:
carbonmean<-lm(C.Mean~ Mean.richness + Diversity + Zoop + Diversity/Phyto +
Zoop*Diversity/Phyto)
where, *Mean.richness* is a covariate*, Zoop* is a categorical variable (the
species), *Diversity* is a categorical variable (Low or High), and
2005 Nov 24
2
type III sums of squares in R
Hi everyone,
Can someone explain me how to calculate SAS type III sums of squares in
R? Not that I would like to use them, I know they are problematic. I
would like to know how to calculate them in order to demonstrate that
strange things happen when you use them (for a course for example). I
know you can use drop1(lm(), test="F") but for an lm(y~A+B+A:B), type
III SSQs are only
2005 Apr 20
6
Anova - adjusted or sequential sums of squares?
Hi
I am performing an analysis of variance with two factors, each with two
levels. I have differing numbers of observations in each of the four
combinations, but all four combinations *are* present (2 of the factor
combinations have 3 observations, 1 has 4 and 1 has 5)
I have used both anova(aov(...)) and anova(lm(...)) in R and it gave the
same result - as expected. I then plugged this into
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
2003 Feb 15
1
tests for spericity
Dear R-help,
Does any one know of a function/package in R that will test the assumption of
spericity in a split-plot analysis of variance? How are people dealing with
this issue in R?
With best wishes and kind regards I am
Sincerely,
Corey A. Moffet
Support Scientist
University of Idaho
Northwest Watershed Research Center
800 Park Blvd, Plaza IV, Suite 105
Boise, ID 83712-7716
(208) 422-0718
2002 Mar 21
1
help with print and ways to display results
Hi all,
I have some (stupid) problems to display results and
i don't find a solution.
1-
res<-c(1,2,3)
I would like to display
>Results are 1 2 3
The following command cat(paste("Results are ",res,"\n")) give me
>my results are 1 my results are 2 my results are 3
2- res<-cbind(c(1,2),c(2,3))
I would like to display
>Result is the matrix 1 2
2010 Jun 02
0
Nested ANOVA with covariate using Type III sums of squares in R
Hello,
I have been trying to get an ANOVA table for a linear model containing a
single nested factor, two fixed factors and a covariate:
carbonmean<-lm(C.Mean~ Mean.richness + Diversity + Zoop + Diversity/Phyto
+ Zoop*Diversity/Phyto)
where, Mean.richness is a covariate, Zoop is a categorical variable (the
species), Diversity is a categorical variable (Low or High), and Phyto
(community
2003 Jan 21
1
Modified F-test for heterogeneous error variances
Dear R-help:
Does anyone know of a package in R that will do Welch's modified F-test
for heterogeneous error variances? Are there other statistical techniques
available in R that test the equality of means when homoscedastisity
is violated? 't.test' does this in the pairwise sense when var.equal =
TRUE.
With best wishes and kind regards I am
Sincerely,
Corey A. Moffet
Support
2003 Dec 02
1
Is there a way to use CGIwithR in Windows?
Dear R-Help,
Does anyone know of a way to use CGIwithR in Windows? David Firth the
author of CGIwithR states "It ought to be possible to adapt it for use also
in conjunction with web servers running under Windows NT ... but the author
has no plans for that." I have developed some applications in R that I would
like to make available through a web interface using CGIwithR but at this
2003 Mar 06
6
type III Sum Sq in ANOVA table - Howto?
Hello,
as far as I see, R reports type I sums of squares. I'd like to get R to
print out type III sums of squares.
e.g. I have the following model:
vardep~factor1*factor2
to get the type III sum of squares for factor1 I've tried
anova(lm(vardep~factor2+factor1:factor2),lm(vardep~factor1*factor2))
but that didn't yield the desired result.
Could anyone give me a hint how to proceed?
2002 Aug 20
1
override ask = TRUE in plot.formula
I am having difficulty with plot.formula.
For example:
-------------------
dat <- data.frame(y = c(1,1,1,2,2,2,3,3,3,4,4,4),
x1 = as.ordered(c(1,1,1,1,1,1,2,2,2,2,2,2)),
x2 = as.ordered(c(1,1,1,2,2,2,1,1,1,2,2,2)))
plot(y ~ x1 + x2, data = dat) # Works fine "interactively" asking:
# "Hit <Return> to see next plot:"
#
2004 Apr 29
1
model.tabels warning refers to wrong function (PR#6839)
Full_Name: Corey A. Moffet
Version: 1.8.1
OS: Windows 2000 and RHL 9
Submission from: (NULL) (199.133.140.156)
The function model.tables.aov and perhaps other model.tables methods refer the
user to use the function se.contrasts when the design is unbalanced. The
function name is se.contrast (singular).
2004 Aug 11
2
type III sum of squares
R-help
What are the strengths and weakness of 'aov' in 'car' package?
My model looks something like this :
library(car)
aov(lm(fish.length~zone*area,data=my.data))
Thank you
Luis Ridao Cruz
Fiskiranns??knarstovan
N??at??n 1
P.O. Box 3051
FR-110 T??rshavn
Faroe Islands
Phone: +298 353900
Phone(direct): +298 353912
Mobile: +298 580800
Fax:
2006 Aug 26
5
Type II and III sum of square in Anova (R, car package)
Hello everybody,
I have some questions on ANOVA in general and on ANOVA in R particularly.
I am not Statistician, therefore I would be very appreciated if you answer
it in a simple way.
1. First of all, more general question. Standard anova() function for lm()
or aov() models in R implements Type I sum of squares (sequential), which
is not well suited for unbalanced ANOVA. Therefore it is better
2003 Aug 18
2
type I and type III sums of squares
Hello-
I have been digging around in the FAQ's and online looking for an answer
to my questions, and perhaps someone here can help me.
For a statistical experiment, I need to run 3,000,000 ANOVAs, which is
taking me a very long time. As a result, I have recoded my analyses in
C. However, I cannot find the formula to calculate either the type I or
type III sums of squares (in the case of