Re: [R] ancova for dependent response

2016-11-21 Thread Jeff Newmiller
Yes. https://lmgtfy.com/?q=R+ancova -- Sent from my phone. Please excuse my brevity. On November 21, 2016 9:09:58 PM PST, li li wrote: >Hi all, >Is there an R function which can handles dependent response in Analysis >of covariance model. The dependence structure is known and is there to >accoun

Re: [R] ANCOVA post-hoc test

2012-02-12 Thread David Winsemius
On Feb 12, 2012, at 7:39 AM, Evagelopoulos Thanasis wrote: Could you please help me on the following ANCOVA issue? This is a part of my dataset: sampling dist h 1wi 200 0.8687212 2wi 200 0.8812909 3wi 200 0.8267464 4wi0 0.8554508 5wi0

Re: [R] ANCOVA post-hoc test

2012-02-12 Thread Richard M. Heiberger
I am at my machine now. The subset of the data you sent has only two groups and doesn't have a significant interaction. Therefore I can't talk about specifics for your example. The glht test you did compared the means of the sampling factor ignoring the dist covariate. Your description said you

Re: [R] ANCOVA post-hoc test

2012-02-12 Thread Rmh
ancova in HH is a wrapper for aov that displays a set of lattice plots. the problem you are seeing is probably that glht ignores covariates (with an appropriate message) unless you specify an optional argument. I will reply in more detail when i am at my computer. in the meantime, look at ?glht

Re: [R] ANCOVA post-hoc test

2012-02-12 Thread peter dalgaard
Inline below On Feb 12, 2012, at 13:39 , Evagelopoulos Thanasis wrote: [...] > > Because there exist significantly different regression slopes, I did a post > hoc test with glht() to find out between which samplings: > >> summary(glht(mod, linfct=mcp(sampling="Tukey"))) > I believe this compa

Re: [R] ANCOVA for linear regressions without intercept

2011-04-05 Thread Yusuke Fukuda
PM To: Yusuke Fukuda; 'Peter Ehlers' Cc: r-help@r-project.org Subject: RE: [R] ANCOVA for linear regressions without intercept Hi Yusuke, Does the following get what you are after? ### Make some test data. > set.seed(123) > edf <- data.frame(sex = c(rep("Male"

Re: [R] ANCOVA for linear regressions without intercept

2011-04-05 Thread Yusuke Fukuda
rc.ca] Sent: Tuesday, 5 April 2011 12:08 PM To: Yusuke Fukuda; 'Peter Ehlers' Cc: r-help@r-project.org Subject: RE: [R] ANCOVA for linear regressions without intercept Hi Yusuke, Does the following get what you are after? ### Make some test data. > set.seed(123) > edf <- data

Re: [R] ANCOVA for linear regressions without intercept

2011-04-04 Thread Steven McKinney
ot;blue", lty = 2) > abline(a = 0, b = coef(lmr1f)[2], col = "orange", lty = 2, lwd = 4) > The other two tests can be set up and run similarly. Don't forget to adjust for multiple comparisons... HTH Steve Steven McKinney, Ph.D. Statistician Molecular Oncology an

Re: [R] ANCOVA for linear regressions without intercept

2011-04-04 Thread Yusuke Fukuda
ssage- From: Peter Ehlers [mailto:ehl...@ucalgary.ca] Sent: Saturday, 2 April 2011 1:35 AM To: Yusuke Fukuda Cc: 'Bert Gunter'; r-help@r-project.org Subject: Re: [R] ANCOVA for linear regressions without intercept See inline. On 2011-03-31 22:22, Yusuke Fukuda wrote: > Thanks Ber

Re: [R] ANCOVA for linear regressions without intercept

2011-04-01 Thread Peter Ehlers
usuke Fukuda Cc: r-help@r-project.org Subject: Re: [R] ANCOVA for linear regressions without intercept If you haven't already received an answer, a careful reading of ?formula will provide it. -- Bert On Wed, Mar 30, 2011 at 11:42 PM, Yusuke Fukuda wrote: Hello R experts I have two linear regre

Re: [R] ANCOVA for linear regressions without intercept

2011-03-31 Thread Yusuke Fukuda
fference is significant or not. Thanks for your help. From: Bert Gunter [mailto:gunter.ber...@gene.com] Sent: Friday, 1 April 2011 12:56 AM To: Yusuke Fukuda Cc: r-help@r-project.org Subject: Re: [R] ANCOVA for linear regressions without intercept If y

Re: [R] ANCOVA for linear regressions without intercept

2011-03-31 Thread Bert Gunter
If you haven't already received an answer, a careful reading of ?formula will provide it. -- Bert On Wed, Mar 30, 2011 at 11:42 PM, Yusuke Fukuda wrote: > > Hello R experts > > I have two linear regressions for sexes (Male, Female, Unknown). All have a > good correlation between body length (r

Re: [R] ANCOVA in R, single CoVar, two Variables

2010-05-12 Thread Tom W
Thankyou all for the replies! I am sure you can guess the next question that is coming... I expanded the code (and the data set) to now include a third type "C", which I made VERY similar to A: anco <- read.table(tmp, header=TRUE) close.connection(tmp) wind <- data.frame(day=rep(anco$day, 3)

Re: [R] ANCOVA in R, single CoVar, two Variables

2010-05-11 Thread RICHARD M. HEIBERGER
I recommend the ancova function in the HH package. install.packages("HH") library(HH) example(ancova) ?ancova For your example, tmp <- textConnection( "day A B 0 10.010.0 7 9.0 9.1 14 8.0 8.2 21 7.0 7.3 28 6.0 6.4 35 5.0 5.5 42

Re: [R] ANCOVA with defined error terms

2009-08-25 Thread hpdutra
Could someone or Richard explain to me what he meant by "This also shows a singular Error(). We look at the data and see that plot is identical to the three-way veget:fruit:block interaction." It seems to me that I just needed to recoded the plots, in order to get rid of the Error message. If t

Re: [R] ANCOVA with defined error terms

2009-08-23 Thread hpdutra
When we ran a regular ANOVA we showed that both mice and raccoons respond positively to cover. So we decided to use raccoons as a co-variate because those are mouse predators and their presence per se could explain part of the variation on mice activity. That is the reason why I'm running this AN

Re: [R] ANCOVA with defined error terms

2009-08-23 Thread Richard M. Heiberger
Ok, now we can talk. 1. covariates: coon Your model specification put coon sequentially last, effectively testing the hypothesis that the slope associated with coon, after adjusting for all the factors, is zero. My model place coon sequentially first, effectively testing the hypotheses that the

Re: [R] ANCOVA with defined error terms

2009-08-23 Thread hpdutra
What does the command c:\progra~1\R\R-2.9.1\bin\Rgui --vanilla do? At first I thought that I could run it from R. But then it did not work. I'm using a mac, and I don't know how access MSDOS in a mac. I actually installed R on the pc and tried to run the command from MSDOS and it also didn't wor

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread Richard M. Heiberger
Your model formula cannot be correct. The phrase Error(block/plot, data = track) is wrong. It has to be something like this Error(block/plot), data = track The Error function requires a well-defined formula. The "," character cannot be inside the Error function. You misunderstood my use of

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread hpdutra
I can actually run the code from my post. I used the nabble for my list server http://www.nabble.com/ANCOVA-with-defined-error-terms-td25055311.html#a25100032 I don't know which server you use, but that one is not truncated, I can copy the code just fine and run it. Anyway, here it is again summ

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread Richard M. Heiberger
Your email program truncated the model. It would not run, hence was not reproducible. The last few characters of the first line are +Error(block/plot, which is syntactically impossible because there is no closing parenthesis before the comma. Try executing your email and see the difficulty.

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread hpdutra
Hi Richard, there are no empty cells. I transform everything into factor, except the co-variate coon. Here is the full analysis with dput of the data. I'm afraid I have not enough DF for the thre-way interaction using your model as well. 12 plots divided in 3 blocks, each plot assigned to 2 cros

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread Richard M. Heiberger
The three-way interactions you mention are included in the model formula I suggested. If they didn't appear in the expansion, it suggests that you have some aliasing due to empty cells. I can't do any more without your dataset. You can post your dataset with random response values. The exact dat

Re: [R] ANCOVA with defined error terms

2009-08-22 Thread hpdutra
Thank you Richard, this works. But, the model you suggested me lacks some between subjects interactions, namely: veget:time:block fruit:time:block. According to Sokal and Rohlf I need to report those as well. Also, any ideas why the sum of squares on my model are different from yours summar

Re: [R] ANCOVA with defined error terms

2009-08-20 Thread Richard M. Heiberger
Yes, I meant summary(). anova() isn't defined for aovlist objects and summary() is. Warning message: In aov(kotz.mice ~ kotz.coon + block * veget * fruit * time - block:veget:fruit:time + : Error() model is singular You will need to investigate the singular Error() model. You might want

Re: [R] ANCOVA with defined error terms

2009-08-20 Thread hpdutra
Thanks Richard, I tried running the analysis the way you suggested but here is the error that I get > track.aov <- aov(mice ~ coon+block*veget*fruit*time - > block:veget:fruit:time + + Error(block/plot), data = track) Warning message: In aov(kotz.mice ~ kotz.coon + block * veget

Re: [R] ANCOVA with defined error terms

2009-08-19 Thread Richard M. Heiberger
track.aov <- aov(mice ~ coon + block*veget*fruit*time - block:veget:fruit:time + Error(block/plot), data = track) anova(track.aov) I think this is what you are looking for. This model in words says, What is the effect of the four-way crossing after adjusting fo

Re: [R] Ancova

2009-01-30 Thread John Fox
Dear Patrick, > -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf Of Patrick B é dard > Sent: January-30-09 6:31 PM > To: r-help@r-project.org > Subject: [R] Ancova > > Hello, > > I have the following ancova: > my_ancova = aov(x~a+b

Re: [R] ANCOVA

2008-12-09 Thread Greg Snow
ANCOVA usually is used when you have a numerical covariate that you want to adjust for, your description does not include any, so a regular anova (aov function) can be used. If you do have 1 or more covariates to adjust for, then it can be thought of as a regression problem (ANCOVA is a special

Re: [R] ANCOVA/glm missing/ignored interaction combinations

2008-09-03 Thread ONKELINX, Thierry
Lara, The first category is nor missing, nor ignored. It is used as the reference. So the temperature effect for semio1 is only temperature. The temperature effect for semio2 is temperature + temperature:semio2. For semio3 it is temperature + temperature:semio3. Hence the main effect of temperatur

Re: [R] ANCOVA/glm missing/ignored interaction combinations

2008-09-03 Thread Mark Difford
And perhaps I should also have added: fit your model without an intercept and look at your coefficients. You should be able to work it out from there quite easily. Anyway, you now have the main pieces. Regards, Mark. Mark Difford wrote: > > Hi Lara, > >>> And I cant for the life of me work ou

Re: [R] ANCOVA/glm missing/ignored interaction combinations

2008-09-03 Thread Mark Difford
Hi Lara, >> And I cant for the life of me work out why category one (semio1) is being >> ignored, missing >> etc. Nothing is being ignored Lara --- but you are ignoring the fact that your factors have been coded using the default contrasts in R, viz so-called treatment or Dunnett contrasts. Tha

Re: [R] ANCOVA: Next steps??

2008-08-16 Thread Prof Brian Ripley
On Sat, 16 Aug 2008, Brown, Heidi wrote: Having spent the last few weeks trying to decipher R, I feel I may finally be getting somewhere, but i'M still in need of some advice and all my tutors seem to be on holiday! Basically a bit of background, I have data collected on a population of Liza

Re: [R] Ancova: formula with a common intercept

2008-06-02 Thread Rolf Turner
On 3/06/2008, at 2:56 AM, Daniel Brewer wrote: I have some data with two categorises plus/minus (p53) and a particular time (Time) and the outcome is a continuous vairable (Result). I set up a maximum model. ancova <- lm(Result~Time*p53) summary(ancova) .. Coefficients: Esti

Re: [R] ANCOVA error again

2008-04-21 Thread Gavin Simpson
On Mon, 2008-04-21 at 17:21 +0200, Birgit Lemcke wrote: > Hello Gavin, > > thanks for you answer. > If I use it without " with" I get back the same error. > The "with" thing was only to try out for functions that do not > contain a data-argument. I still try to learn and therefor I > sometimes

Re: [R] ANCOVA error again

2008-04-21 Thread Birgit Lemcke
Hello Gavin, thanks for you answer. If I use it without " with" I get back the same error. The "with" thing was only to try out for functions that do not contain a data-argument. I still try to learn and therefor I sometimes just try. It is understood that I am on the way to simplify the mode

Re: [R] ANCOVA error again

2008-04-21 Thread Gavin Simpson
On Mon, 2008-04-21 at 15:43 +0200, Birgit Lemcke wrote: > Hello R users! > > I got again an error message. Something here is causing compiled code to segfault ("crash"). I don't know what the problem is here exactly --- I'll let those much more acquainted with R look into that --- but you seem to

Re: [R] ANCOVA error again

2008-04-21 Thread Birgit Lemcke
Hello R users! I got again an error message. I used this code: with (FemMal85_Sex, { ModelFemMal85<- glm (Sex~outLatTep_like_other*outLatTep_like_conduplicate*outLatTep_keeled_w inged*spathellae_co

Re: [R] ANCOVA

2008-04-21 Thread Birgit Lemcke
Hello John, I am really sorry about that. I wanted to include the code but I forgot and you are completely right, I forgot the family-argument. Thanks for the help. B. Am 21.04.2008 um 14:50 schrieb John Fox: > Dear Brigit, > > My guess is that you forgot to specify the argument family=binom

Re: [R] ANCOVA

2008-04-21 Thread John Fox
Dear Brigit, My guess is that you forgot to specify the argument family=binomial in the call to glm(). Had you included the commands that you used as well as the error that was produced, it wouldn't be necessary to guess. I hope this helps, John On Mon, 21 Apr 2008 14:23:13 +0200 Birgit Lemck

Re: [R] Ancova doesn't return test statistics

2007-11-15 Thread Gustaf Rydevik
On Nov 15, 2007 4:36 PM, Johan A. Stenberg <[EMAIL PROTECTED]> wrote: > Dear all, > > I'm quite sure that this is a stupid question, but I'll ask anyway. > I want to perform an ANCOVA with two continuous factors and three > categorical factors. > > Plant population growth rate (GR) = dependent vari

Re: [R] Ancova doesn't return test statistics

2007-11-15 Thread Richard M. Heiberger
Your model is fully saturated. It specifies terms that use up all degrees of freedom. There are no degrees of freedom left over for a Residual term and therefore there is no denominator for the tests. When you drop one term, then those degrees of freedom are left over, that is they form the Res

Re: [R] Ancova doesn't return test statistics

2007-11-15 Thread Marc Schwartz
On Thu, 2007-11-15 at 16:36 +0100, Johan A. Stenberg wrote: > Dear all, > > I'm quite sure that this is a stupid question, but I'll ask anyway. > I want to perform an ANCOVA with two continuous factors and three > categorical factors. > > Plant population growth rate (GR) = dependent variable >