Re: [R] ANOVA in R

2018-10-10 Thread Jim Lemon
Hi again, Two things, I named the data frame SR as shown in the model. The other is for those who may wish to answer the OP. The mediafire website is loaded with intrusive ads and perhaps malware. Jim On Thu, Oct 11, 2018 at 9:02 AM Jim Lemon wrote: > > Hi Tranh, > I'm not sure why you are

Re: [R] ANOVA in R

2018-10-10 Thread Jim Lemon
Hi Tranh, I'm not sure why you are converting your variables to factors, and I think the model you want is: lm(KIC~temperature+AC+AV+Thickness+temperature:AC+ temperature:AV+temperature:thickness+AC:AV+ AC:thickness+AV:thickness,SR) Note the colons (:) rather than asterisks (*) for the

Re: [R] ANOVA in R

2018-10-10 Thread Paul Johnson
We cannot read your message. Should post pure text, not html. Hm, my phone now may post html, must try to stop. Your R code not legible. It seems to be output? Lines all run together. I tried find articles you mention, but "not found" resulted. You should use aov() for fitting, then get post hoc

Re: [R] ANOVA Permutation Test

2018-09-03 Thread Juan Telleria Ruiz de Aguirre
Thank you all for your **very good** answers: Using aovp(..., perm="Exact") seems to be the way to go for small datasets, and also I should definitely try ?kruskal.test. Juan [[alternative HTML version deleted]] __ R-help@r-project.org

Re: [R] ANOVA Permutation Test

2018-09-03 Thread S Ellison
> This package uses a modified version of aov() function, which uses > Permutation Tests > > I obtain different p-values for each run! Could that be because you are defaulting to perm="Prob"? I am not familiar with the package, but the manual is informative. You may have missed something when

Re: [R] ANOVA Permutation Test

2018-09-03 Thread Meyners, Michael
Juan, Your question might be borderline for this list, as it ultimately rather seems a stats question coming in R disguise. Anyway, the short answer is that you *expect* to get a different p value from a permutation test unless you are able to do all possible permutation and therefore use

Re: [R] ANOVA Permutation Test

2018-09-03 Thread Michael Dewey
Dear Juan I do not use the package but if it does permutation tests it presumably uses random numbers and since you are not setting the seed you would get different values for each run. Michael On 03/09/2018 16:17, Juan Telleria Ruiz de Aguirre wrote: Dear R users, I have the following

Re: [R] ANOVA test to decide whether to use multiple linear regression or linear mixed effects model

2017-08-15 Thread S Ellison
> I am trying to decide between using a multiple linear regression or a linear > mixed effects model for my data: > ... > but I keep getting the following error code: > > Error in anova.lmlist (object, ...): > > models were not all fitted to the same size of dataset anova is defaulting to

Re: [R] Anova() type iii SS plots and diagnostics

2016-07-19 Thread Fox, John
Dear Pamela, I'm afraid that this question seems confused. Type III sums of squares are computed for a linear model -- it's the *linear model* that you'd check, in the usual manner, for outliers, etc., and this has nothing to do with how the ANOVA table for the model is computed. Best, John

Re: [R] ANOVA test

2014-12-27 Thread peter dalgaard
On 27 Dec 2014, at 02:50 , Richard M. Heiberger r...@temple.edu wrote: Kristi, The easiest way to do what you are looking for is the aovSufficient function in the HH package. ## install.packages(HH) ## if you don't have it yet library(HH) B.aov - aovSufficient(mean ~ site, data=B,

Re: [R] ANOVA test

2014-12-26 Thread Bert Gunter
This is a statistical question primarily and, as such, is off topic here. Either consult a local statistical expert or post to a statistical site like stats.stackexchange.com . Cheers, Bert Bert Gunter Genentech Nonclinical Biostatistics (650) 467-7374 Data is not information. Information is

Re: [R] ANOVA test

2014-12-26 Thread peter dalgaard
You could at least say that no, that is patently wrong! There are ways to reconstruct an ANOVA from means, sd, and group sizes, but this isn't it. In fact, the group sizes are not even used in the code. I agree about the need for a statistical expert. Fundamental misunderstandings seem to be

Re: [R] ANOVA test

2014-12-26 Thread Richard M. Heiberger
Kristi, The easiest way to do what you are looking for is the aovSufficient function in the HH package. ## install.packages(HH) ## if you don't have it yet library(HH) B.aov - aovSufficient(mean ~ site, data=B, sd=B$SE, weights=c(3,3,3,3)) summary(B.aov) You must have the sample size for each

Re: [R] ANOVA and permutation tests : beware of traps

2014-09-23 Thread Joshua Wiley
Hi Stephane, This is the well known result of limitted floating point precision (e.g., http://www.validlab.com/goldberg/addendum.html). Using a test of approximate rather than exact equality shows R yields the correct answer: nperm - 1 Fperm - replicate(n=nperm, anova(lm(sample(Y) ~ F,

Re: [R] ANOVA and permutation tests : beware of traps

2014-09-23 Thread Prof Brian Ripley
Beware of the trap of listening to people with no knowledge of basic numerical methods! It really is basic that the results of floating-point computer calculations depends on the order in which they are done (and the compiler can change the order). Using == on such calculations is warned

Re: [R] anova

2014-08-21 Thread Lynn Govaert
I pressed enter to soon. Again Hi all, I have troubles with doing an anova. So I have the following variables: a variable group with two levels, a continuous variable trait and within each group we have 12 organisms (clone) and for each clone we have 5 replicates. So we want to see if for the

Re: [R] anova

2014-08-21 Thread Sarah Goslee
Hi Lynn, Please read the posting guide, this document: http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example and don't post in HTML. (See your own email copied below for why.) Sarah On Thu, Aug 21, 2014 at 6:08 AM, Lynn Govaert lynn.gova...@gmail.com wrote: Hi

Re: [R] anova

2014-08-21 Thread Bert Gunter
... and you do get P values; you just don't understand what you're looking at, which is more or less what you said. This is not a statistical help site. You should seek local statistical consulting advice or post on a statistical help site (caveat emptor!) like stats.stackexchange.com, not here.

Re: [R] ANOVA for RCBD, two factors: how to plot residuals?..

2014-07-16 Thread Richard M. Heiberger
## Manuel, ## Please look at the maiz example in ?mmc in the HH package. install.packages(HH) ## if necessary library(HH) ?mmc ## After the full maiz example, then you need one more command maiz.proj - proj(maiz.aov) maiz.proj ## I think you are looking for maiz.proj$Within[, Residuals] ##

Re: [R] ANOVA for proportions with large mass on an extreme of [0, 1]

2014-06-21 Thread Bert Gunter
Although your queries certainly intersect R, they are primarily about statistical modeling, which is OT for this list. Your issues also appear to be complex. I would therefore suggest that you eschew remote Internet advice and consult a local statistical expert for help. Cheers, Bert Bert Gunter

Re: [R] ANOVA for proportions with large mass on an extreme of [0, 1]

2014-06-21 Thread Joaquin Rapela
Bert, My queries are directly related to R: 1. Can the R package frm can be used to compare nested models. If so, how. 2. Are there alternative R packages to perform ANOVAs on a dependent variable that is a proportion with significant mass one one extreme? Also, my statistical problem is well

Re: [R] ANOVA repeated mesures

2013-12-23 Thread PIKAL Petr
Hi You have only single value for each participant in each gruppo and AFAIK you can not do statistic on single value. You can check differences among participants fit-lm(valor~participantes, data=df2) fit-lm(valor~participantes, data=df2) anova(fit) Analysis of Variance Table Response:

Re: [R] ANOVA in R

2013-12-07 Thread Bert Gunter
I think you start by doing your homework: 1. Read An Inroduction to R (ships with R) or other R online tutorial. There are many good ones. 2. Use R's Help system: ?aov ?lm ?anova there will be relevant links in these docs that you should follow, especially to the use of formulas for model

Re: [R] Anova split by factors

2013-11-18 Thread ONKELINX, Thierry
Dear Catalin, Have a look at the plyr package. library(plyr) dlply( eg, .(Exp), function(x) { aov(masa.uscat.tr~Clona,data=x) } ) Best regards, ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and

Re: [R] ANOVA for mixture experiment

2013-07-15 Thread S Ellison
But the ANOVA results is incorrect when I use aov.out = aov(Response~-1+x1*x2*x3). First, this doesn't work at all. Your variables are in upper case and your data environment is not specified, so you must have done something else. I can get an answer using something like

Re: [R] ANOVA Estimated effects may be unbalanced

2013-05-19 Thread Jim Lemon
On 05/20/2013 10:52 AM, Luis Fernando García Hernández wrote: Dear All, This is a data relating leg shaking on differenntre treatments. I reused several individuals so I want to know 1) if there are significative differences on shaking per treatment and 2) if the reused individuals presented

Re: [R] ANOVA Estimated effects may be unbalanced

2013-05-19 Thread Bert Gunter
I would say that the OP should seek local statistical help, as he appears to be out of his statistical depth. This would appear to be a mixed effects models-type setup, but a local statistical expert would be much better able to judge what the goals of the study were and what sort of approach,

Re: [R] Anova und Tukey HSD

2013-05-13 Thread Meyners, Michael
Jochen, a) this is an English-spoken mailing list; other languages are not encouraged nor will they typically generate a lot of replies... b) your code is fine, so this is not an R-issue; you are rather stuck with some of the stats background -- you might want to see a friendly local

Re: [R] Anova unbalanced

2013-04-17 Thread Jose Iparraguirre
Dear Claudia, Your question has been posed on many previous occasions. The (short) answer has always been the same: have a look at the Anova function in the car package but before doing that, get a copy of John Fox's Applied Regression Analysis and Generalized Linear Models book. Best, José

Re: [R] anova comparisons

2013-02-23 Thread Rolf Turner
On 02/23/2013 08:55 PM, Robert Zimbardo wrote: I have several linear models on the same data: m1 - lm(y ~ poly(x,1)) m2 - lm(y ~ poly(x,2)) m3 - lm(y ~ poly(x,3)) What I don't understand is why anova(m1, m2, m3, test=F) - yields the same RSS and SS values, but a different p-value from

Re: [R] anova comparisons

2013-02-23 Thread peter dalgaard
On Feb 23, 2013, at 10:06 , Rolf Turner wrote: What am I missing? A basic understanding of the theory of linear models. This really has little to do with R. Go and read a good intro to linear modelling. Insofar as your question has anything to do with R: When you do

Re: [R] ANOVA repeated measures and post-hoc

2012-12-30 Thread Helios de Rosario
A (late) update to this question: On Fri Aug 17 07:33:29, Henrik Singmann wrote: Hi Diego, I am struggeling with this question also for some time and there does not seem to be an easy and general solution to this problem. At least I haven't found one. However, if you have just one

Re: [R] Anova

2012-11-27 Thread Jose Iparraguirre
Hi, You can use the car package and choose Type-III test. Also, have a look at the package easyanova. Regards, José José Iparraguirre Chief Economist Age UK -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of humming-bird Sent: 27

Re: [R] Anova

2012-11-27 Thread S Ellison
Now my question: Am I allowed to use these functions given that my data is unbalanced? Unusually, Yes, assuming all the other requisite assumptions are reasonably well satisfied. One-way ANOVA interpretation is not much affected by imbalance because (among other things) with only one factor

Re: [R] anova test for variables with different lengths

2012-10-16 Thread Jose Iparraguirre
Hi Sachin, You may find this tutorial useful: http://goanna.cs.rmit.edu.au/~fscholer/anova.php And you'll need the car package; but become yourself familiar with Type I, II and III sums of squares models before running the Anova; the tutorial explains these in detail. Hope it helps. José

Re: [R] anova test for variables with different lengths

2012-10-16 Thread S Ellison
I want to test whether the MEAN of two different variables, (and different number of observations) are the same. I am trying to use the anova test but it doesn't seem to like that the number of observations are different: a=c(1:5) b=c(1:3) aov_test=aov(a~b) Error in

Re: [R] Anova, F statistics, P-values

2012-10-06 Thread Jhope
Thank you for the replies. I am actually trying to gain p-values and f values, and tried the below script but unsuccessful. 1) I have read in another forum to use the package lmer but apparently it does not exist. 2) Then I tried the pvals.fnc but it is not a function. 3) I read also that a

Re: [R] Anova

2012-10-05 Thread Rui Barradas
Hello, You're thinking of ?aov. anova() does _not_ have a formula interface, it would be anova(lm(HSuccess ~ Veg, data = data.to.analyze)) or aov(HSuccess ~ Veg, data = data.to.analyze) Hope this helps, Rui Barradas Em 05-10-2012 09:27, Jhope escreveu: Hi R-listers, I am trying to do an

Re: [R] Anova

2012-10-05 Thread John Fox
Dear Jean, On Fri, 5 Oct 2012 01:27:55 -0700 (PDT) Jhope jeanwaij...@gmail.com wrote: Hi R-listers, I am trying to do an ANOVA for the following scatterplot and received the following error: library(car) scatterplot(HSuccess ~ Veg, data = data.to.analyze,

Re: [R] Anova and tukey-grouping

2012-09-30 Thread arun
whether the str() I got matches with yours. Have a great day! A.K.     - Original Message - From: Landi ent-ar...@gmx.de To: r-help@r-project.org Cc: Sent: Friday, September 28, 2012 10:35 AM Subject: Re: [R] Anova and tukey-grouping Hello ! Thanks for your advice. I tried

Re: [R] Anova and tukey-grouping

2012-09-30 Thread Landi
typohne.csv http://r.789695.n4.nabble.com/file/n4644635/typohne.csv Hello arun kirshna, I checked str() but I do not see any mistake. Find attached a subset of my data (did you mean this with dput() ?) Typ= treatment abun= abundance div= diversity, number of species best wishes. -- View

Re: [R] Anova and tukey-grouping

2012-09-30 Thread Landi
Hello again ! It worked exactly the same way as yours! I'm kind of astonished, because in my opinion our skripts are the same (obviously not...). Whatever! It works :-D Tomorrow (as where I live it's already evening...sunday) will be a great day, indeed, and I can go on with analysis ! I really

Re: [R] Anova and tukey-grouping

2012-09-28 Thread arun
HI, I guess there is a mistake in your code.  You should have used typ instead of abun as abun is the dependent variable. summary(fm1 - aov(breaks ~ wool + tension, data = warpbreaks)) myresults    -  TukeyHSD(fm1, tension, ordered = TRUE) library(agricolae) HSD.test(fm1,wool,group=TRUE)

Re: [R] Anova and tukey-grouping

2012-09-28 Thread Landi
Hello ! Thanks for your advice. I tried it, but the output is the same: HSD.test(anova.typabunmit, typ, group=TRUE) Name: typ ds.typabunmit$typ I don't get the values...!?!? -- View this message in context: http://r.789695.n4.nabble.com/Anova-and-tukey-grouping-tp4644485p4644513.html

Re: [R] Anova and tukey-grouping

2012-09-28 Thread arun
, 2012 10:35 AM Subject: Re: [R] Anova and tukey-grouping Hello ! Thanks for your advice. I tried it, but the output is the same: HSD.test(anova.typabunmit, typ, group=TRUE) Name:  typ ds.typabunmit$typ I don't get the values...!?!? -- View this message in context: http://r.789695.n4

Re: [R] Anova problem with order of terms in model

2012-09-26 Thread Modi2020
Please check if your independent variables or Xs are independent. If they are not that can affect the sequential decomposition. -- View this message in context: http://r.789695.n4.nabble.com/Anova-problem-with-order-of-terms-in-model-tp791744p4644320.html Sent from the R help mailing list

Re: [R] ANOVA repeated measures and post-hoc

2012-08-16 Thread Robert Baer
Check out: http://rtutorialseries.blogspot.com/2011/02/r-tutorial-series-two-way-repeated.html On 8/15/2012 11:32 AM, Diego Bucci wrote: Hi, I performed an ANOVA repeated measures but I still can't find any good news regarding the possibility to perform multiple comparisons. Can anyone help

Re: [R] ANOVA repeated measures and post-hoc

2012-08-16 Thread Henrik Singmann
Hi Diego, I am struggeling with this question also for some time and there does not seem to be an easy and general solution to this problem. At least I haven't found one. However, if you have just one repeated-measures factor, use the solution describe by me here:

Re: [R] anova in unbalanced data

2012-08-14 Thread S Ellison
-Original Message- Say I have the following data: a-data.frame(col1=c(rep(a,5),rep(b,7)),col2=runif(12)) a_aov-aov(a$col2~a$col1) summary(aov) Note that there are 5 observations for a and 7 for b, thus is unbalanced. What would be the correct way of doing anova for

Re: [R] anova in unbalanced data

2012-08-13 Thread arun
HI, Check this link: https://stat.ethz.ch/pipermail/r-help/2011-April/273858.html A.K. - Original Message - From: Sachinthaka Abeywardana sachin.abeyward...@gmail.com To: r-help@r-project.org Cc: Sent: Monday, August 13, 2012 10:09 PM Subject: [R] anova in unbalanced data Hi all,

Re: [R] Anova Type II and Contrasts

2012-07-06 Thread David Winsemius
Dear Peter; This is an exact duplicate of a question posted on SO. Cross-posting is deprecated on Rhelp. -- David. On Jul 6, 2012, at 11:06 AM, mails wrote: the study design of the data I have to analyse is simple. There is 1 control group (CTRL) and 2 different treatment groups (TREAT_1

Re: [R] Anova Type II and Contrasts

2012-07-06 Thread John Fox
Dear Peter, Because your model is additive, type-II and type-III tests are identical, and the t-tests for the linear and quadratic coefficients are interpretable. I hope this helps, John John Fox Sen. William McMaster Prof. of Social Statistics

Re: [R] ANOVA help

2012-06-20 Thread David Winsemius
On Jun 19, 2012, at 5:36 PM, James Johnson wrote: Hi All, I have a microarray dataset as follows: expt1 expt2 expt3 expt4 expt 5 gene1val val val val val gene2val val val valval . . .. gene15000

Re: [R] anova of lme objects (model1, model2) gives different results depending on order of models

2012-06-01 Thread Chris Beeley
Well that's that cleared up then. Thanks to all. Chris B. On 31/05/2012 17:51, Albyn Jones wrote: No, both yield the same result: reject the null hypothesis, which always corresponds to the restricted (smaller) model. albyn On Thu, May 31, 2012 at 12:47:30PM +0100, Chris Beeley wrote:

Re: [R] anova of lme objects (model1, model2) gives different results depending on order of models

2012-05-31 Thread Albyn Jones
No, both yield the same result: reject the null hypothesis, which always corresponds to the restricted (smaller) model. albyn On Thu, May 31, 2012 at 12:47:30PM +0100, Chris Beeley wrote: Hello- I understand that it's convention, when comparing two models using the anova function

Re: [R] ANOVA question

2012-05-11 Thread ONKELINX, Thierry
Dear Robert, It is easier to use lm instead of aov if you want coefficients for each group. Note that you can use rnorm vectorised. set.seed(0) N - 100 # sample size MEAN - c(10, 20, 30, 40, 50) VAR - c(20,20,1, 20, 20) LABELS - factor(c(A, B, C, D, E)) # create a data frame with labels df -

Re: [R] ANOVA question

2012-05-11 Thread Robert Latest
Hello Thierry, thanks for your answer! There is one thing, however, that I don't understand. The values labeled B in my data are generated with 1/20th the variance of the others, yet the standard error and confidence intervals are the same for all levels of the factor. How come?

Re: [R] ANOVA problem

2012-05-04 Thread Bert Gunter
Rob: On Fri, May 4, 2012 at 9:18 AM, robgriffin247 rg.rfo...@hotmail.co.uk wrote: Hi, I need to create a data frame containing the results of a number of ANOVA's but I'm having some trouble setting it up (some being enough for me to spend 3 days trying with no progress and be left staring in

Re: [R] ANOVA problem

2012-05-04 Thread Richard M. Heiberger
The following constructs the data.frame that I think the original poster asked for. I don't understand the graph, so I didn't attempt it. I agree with Bert that this might not make sense. Specifically, the distinction between AB01 and AB02 is not modeled, and that is probably the critical

Re: [R] ANOVA problem

2012-05-04 Thread rob.griffin.247
Gee Bert, thanks for the really helpful tip. But if you read my post properly you'll note that I do know how ANOVA's work. The anova of *G* /AB01 /would be some thing like: y=V, fixed=S, Random= L L*S... I didn't want to show a full model formula in case it led people do the wrong path to

Re: [R] ANOVA problem

2012-05-04 Thread rob.griffin.247
Thanks Richard, that works great on the test data, I'll try it out on the full dataset now and let you know how it goes. Thanks a lot! -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-problem-tp4609062p4609400.html Sent from the R help mailing list archive at Nabble.com.

Re: [R] ANOVA in quantreg - faulty test for 'nesting'?

2012-04-21 Thread Roger Koenker
: Galen Sher galens...@gmail.com To: Brian S Cade ca...@usgs.gov Date: 04/20/2012 09:59 AM Subject: Re: [R] ANOVA in quantreg - faulty test for 'nesting'? -- Thanks Brian. I think anova.glm() requires the user to specify the appropriate distribution

Re: [R] ANOVA in quantreg - faulty test for 'nesting'?

2012-04-20 Thread Galen Sher
Date: 04/20/2012 09:59 AM Subject: Re: [R] ANOVA in quantreg - faulty test for 'nesting'? -- Thanks Brian. I think anova.glm() requires the user to specify the appropriate distribution. In the example above, if I use either of the following commands anova(f1,f2

Re: [R] ANOVA Data Error

2012-04-17 Thread David Winsemius
On Apr 17, 2012, at 1:03 PM, MatthewJudd wrote: Hello I am having some trouble performing a simple ANOVA in R I am working with 2001 census tract information regarding religion. I am quite a rookie at this whole R experiance, but I would like to improve my skills. *I read in my data

Re: [R] ANOVA testing over nested MS term

2012-03-18 Thread peter dalgaard
On Mar 18, 2012, at 08:21 , shoreliner11 wrote: I'm still relatively new to R but was wondering if anyone could help me force R to compute the f-statistic etc using the the nested term rather than the residual. In my particular case we were nesting a treatment effect by a replicated tank

Re: [R] anova analysis on factors...

2011-12-08 Thread Sarah Goslee
And a further problem with both approaches: is 11pm (23) really that different from 1am? On Thu, Dec 8, 2011 at 3:28 PM, Michael comtech@gmail.com wrote: Hi all, If we wanted to study the effect on the mean of the hourly data based on the hours within a day... and we wanted to do Anova

Re: [R] anova analysis on factors...

2011-12-08 Thread David Winsemius
On Dec 8, 2011, at 3:28 PM, Michael wrote: Hi all, If we wanted to study the effect on the mean of the hourly data based on the hours within a day... and we wanted to do Anova analysis... We have two choices: Who is we and how were these constraints imposed? Please see below: Why

Re: [R] ANOVA and LSD TEST - contrasting results

2011-11-20 Thread peter dalgaard
On Nov 19, 2011, at 15:37 , Roberto wrote: First of all, thank you for the reply to my topic. Anova summary has shown no significative difference into Treatment (Pr 0.374), otherwise LSD Test has shown difference between 2 Treatment. I suppose that's something strange. It isn't. You

Re: [R] ANOVA and LSD TEST - contrasting results

2011-11-20 Thread Roberto
I didn't meant to rewrite textbook. I asked only for a clarification to my doubt, because I have started to study statistic recently. -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-and-LSD-TEST-contrasting-results-tp4086090p4088810.html Sent from the R help mailing list

Re: [R] ANOVA and LSD TEST - contrasting results

2011-11-19 Thread John Sorkin
Roberto, Please be more specific. What are the differences between ANOVA and LSD that give you concern? John John David Sorkin M.D., Ph.D. Chief, Biostatistics and Informatics University of Maryland School of Medicine Division of Gerontology Baltimore VA Medical Center 10 North Greene Street

Re: [R] ANOVA and LSD TEST - contrasting results

2011-11-19 Thread Roberto
First of all, thank you for the reply to my topic. Anova summary has shown no significative difference into Treatment (Pr 0.374), otherwise LSD Test has shown difference between 2 Treatment. I suppose that's something strange. Roberto -- View this message in context:

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-10 Thread shardman
Hi David, Apologies again and thankyou for your help, I've edited my original post to clarify what I was asking. What I meant was that the factor had only 1 degrees of freedom when it should have had 2 (14 in total), so you're right there were 14 but not in the right place. In SPSS you select

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-10 Thread shardman
Thanks bbolker, that's really helpful. I'll look out for the book too, it could be helpful! Yours, Sam -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-from-imported-data-has-only-1-degree-of-freedom-tp3887528p3891246.html Sent from the R help mailing list archive at

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-09 Thread David Winsemius
On Oct 9, 2011, at 11:10 AM, shardman wrote: Hi, I'm trying to analyse some data I have imported into R from a .csv file but when I carry out the aov command the results show only one degree of freedom when there should be 14. Does anyone know why? I'd really appreciate some help, the

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-09 Thread shardman
Hi David, Thanks for your message. I can assure you this is not homework. I'm working on an ecology project and am trying to analyse the results from the fieldwork. I don't want other people to do the work for me I was just hoping someone might be able to spot where I have made a mistake, I'm

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-09 Thread David Winsemius
On Oct 9, 2011, at 2:08 PM, shardman wrote: Hi David, Thanks for your message. I can assure you this is not homework. I'm working on an ecology project and am trying to analyse the results from the fieldwork. I don't want other people to do the work for me I was just hoping someone might

Re: [R] ANOVA from imported data has only 1 degree of freedom

2011-10-09 Thread Ben Bolker
shardman samuelhardman at hotmail.com writes: Hi, I'm trying to analyse some data I have imported into R from a .csv file but when I carry out the aov command the results show only one degree of freedom when there should be 14. Does anyone know why? I'd really appreciate some help, the

Re: [R] ANOVA/ANCOVA Repeated Measure Mixed Model

2011-10-07 Thread Nick GH
Hi Daniel, Thanks for your response, I don't completely follow. I also should have split this into two questions. Regarding my first question: Daniel Malter wrote: You are modeling Condition * Stimulus * Group as fully interacted fixed effects... A simple random effect for the individual

Re: [R] ANOVA/ANCOVA Repeated Measure Mixed Model

2011-10-06 Thread Daniel Malter
You are modeling Condition * Stimulus * Group as fully interacted fixed effects. I do not actually think that you would need a complex random effect structure for this. A simple random effect for the individual might suffice. You could try to model this with lmer (in the lme4 library) and inspect

Re: [R] ANOVA define as factor or not

2011-09-27 Thread Jean V Adams
HronnE wrote on 09/27/2011 06:27:38 AM: Hi all This is probably a simple problem but somehow I am having much trouble with finding a solution, so I seek your help! I have a data-set with continuous response variables. The explanatory variably is 4xpH treatments (so 8.08, 7.94, 7.81 and

Re: [R] ANOVA define as factor or not

2011-09-27 Thread HronnE
Thank you very much for a quick reply! I had not realized the degrees of freedom changed. It was my lack of understanding of the aov function. I will continue defining the pH as factor for the ANOVA's. Cheers, Hronn - -- Hrönn Egilsdóttir PhD Student Marine Research Institute

Re: [R] ANOVA with many IV's

2011-06-08 Thread Dennis Murphy
Hi: You can try something like this: assuming the factor variables of interest and the response variable are in a data frame named df, ivset - c(comma separated vector of factor names) myaovs - lapply(ivset, function(x) { form - as.formula(substitute(yvar ~ foo, list(foo = as.name(x

Re: [R] ANOVA with many IV's

2011-06-08 Thread Rolf Turner
It is not nearly as complicated as Dennis Murphy makes out. Just do aov(y ~ ., data=X) where X is your data frame with one column (the response) name ``y'' and then any number of other columns which will then form the predictors (which may be either numeric predictors or factors).

Re: [R] ANOVA Residual SS and MS of 0

2011-05-24 Thread Bert Gunter
Where do I begin troubleshooting such a problem? 1. By examining your data to see whether you have entered it correctly. 2. By reading the posting Guide at the bottom of this and every message and doing as it asks (posting a portion of your data and R code so that we can see what you did). 3.

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-11 Thread Rovinpiper
Please read the first two paragraphs of Details from ?formula Ok, I just did. So, If I understand this properly, the term Plot*Day would include both the main effects of a and b and their second order interactions. So it could be written Plot + Day + Plot:Day. The term Plot:Day includes only

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-10 Thread Rovinpiper
So what is the difference between a colon and an asterisk in this code? For that matter what does the slash mean? -- View this message in context: http://r.789695.n4.nabble.com/ANOVA-1-too-few-degrees-of-freedom-tp3493349p3512977.html Sent from the R help mailing list archive at Nabble.com.

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-10 Thread Richard M. Heiberger
David, Please read the first two paragraphs of Details from ?formula You can try out the formulas with the notation expand.formula - function(f) colnames(attr(terms(f), factors)) expand.formula(~a+b) [1] a b expand.formula(~a:b) [1] a:b expand.formula(~a*b) [1] a b a:b

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-06 Thread peter dalgaard
On May 5, 2011, at 23:30 , Rovinpiper wrote: Thanks slre, I seem to be making some progress now. Using a colon instead of an asterisk in the code really changes things. I had been getting residual SS and MS of zero. Which is ridiculous. Now I get much more plausible values. Also,

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-05 Thread S Ellison
Rovinpiper david.j.mee...@gmail.com 04/05/2011 22:43 So this seems to indicate that I have what I want. I have two respiration data points at each plot on each day. Yes; if you had only Plot+Day you'd have a completely balanced full factorial ... for Plot and Day. But I think I now see an

Re: [R] ANOVA

2011-05-05 Thread David Winsemius
On May 5, 2011, at 2:31 PM, Asan Ramzan wrote: Hello R-Help How can i exctact and store the within group mean squared difference from an anova summary table into a varible. In the absence of an example and code it's speculation, but something along the lines of: anova(fit)$`Mean Sq`

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-05 Thread Rovinpiper
Thanks slre, I seem to be making some progress now. Using a colon instead of an asterisk in the code really changes things. I had been getting residual SS and MS of zero. Which is ridiculous. Now I get much more plausible values. Also, When I used an asterisk instead of a colon It wouldn't

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-04 Thread Rovinpiper
This response went to my email: Without your data it's hard to say, but one possibility is that your plots are nested within treatments instead of crossed, or that you have something rather more cunning going on involving the Days. For example if you had 8 days for six of your plots and another 8

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-04 Thread Rovinpiper
And I responded as follows: Hi, Thanks for your advice. I tried using table() to check for missing data. Here are the results: table(Combined.Plot) Combined.Plot 60m A1 B1 B3 B4 C5 C9 D2 D9 F60m F8 Q7 34 34 3434 343434 3434 34 34 34

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-03 Thread Richard M. Heiberger
Most likely your combined.trt is linearly dependent on the combined.plot factor. Try Anova.Trt.D.M.T.Pr.Model - aov(Combined.Rs ~ as.factor(Combined.Plot) . and see if combined.plot now has the 11 df you are anticipating. Rich On Tue, May 3, 2011 at 3:37 PM, Rovinpiper

Re: [R] ANOVA 1 too few degrees of freedom

2011-05-03 Thread Rovinpiper
Hi Richard, Thanks for your advice. I think that your suggestion is that I run the ANOVA with Combined.Plot as a factor. I have tried that does not alleviate the problem. Did I understand you properly? Do you have another idea? Thanks, David -- View this message in context:

Re: [R] ANOVA for stratified cox regression

2011-03-10 Thread Thomas Lumley
On Fri, Mar 11, 2011 at 8:25 AM, Brian McLoone brianbmclo...@gmail.com wrote: This is a follow-up to a query that was posted regarding some problems that emerge when running anova analyses for cox models, posted by Mathias Gondan: Matthias Gondan wrote: * Dear List, I have tried a

Re: [R] ANOVA and Pseudoreplication in R

2011-02-25 Thread Bert Gunter
I can hopefully save bandwidth here by suggesting that this belongs on the R-sig-mixed-models list. -- Bert As an aside, shouldn't you be figuring this out yourself or seeking local consulting expertise? On Fri, Feb 25, 2011 at 9:08 AM, Ben Ward benjamin.w...@bathspa.org wrote: Hi, As part of

Re: [R] anova() interpretation and error message

2011-02-06 Thread Peter Ehlers
See comments inline. On 2011-02-06 03:17, Jinsong Zhao wrote: Hi there, I have a data frame as listed below: Ca.P.Biomass.A P Biomass 1 334.5567 0.287 2 737.5400 0.571 3 894.5300 0.639 4 782.3800 0.5836667 5 857.5900 0.600 6 829.2700 0.588 I have fit the

Re: [R] ANOVA plotting

2011-01-20 Thread Sarah Goslee
I'm not sure what a real ANOVA diagram is supposed to look like, nor do I know what your data look like. But this might get you started: fakedata - runif(100) fakegroups - sample(rep(letters[1:5], each=20)) boxplot(fakedata ~ fakegroups) If that isn't what you're after, a clearer explanation

Re: [R] ANOVA plotting

2011-01-20 Thread Robert Baer
I recently started using R and I have a simple question. I am running R (v. 2.12.1) and Rcmdr (v.1-6.3) on Mac (Snow Leopard). I am using a data set I used before for practicing ANOVA with R, so I know what the results should look like. I can get ANOVA table using both Rcmdr and GUI. However,

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