[R-sig-phylo] axisChrono and axisPhylo

2015-03-02 Thread Jacob Berv
Greetings R-sig-phylo,
This is my first post but happy to join this community

I have been having some trouble with the axisChrono of the phyloch package and 
axisPhylo functions of the ape package that I was hoping someone might be able 
to help me with.

When using either function, the spacing between ticks on the scale is too large 
for the figure I’m trying to generate. I have tried passing variations of 
at=c(1,2,3,4,5), or at=seq(0,10,1) etc, but for either function I get the 
following error:

Error in axis(side = side, at = c(maxi - x), labels = abs(x * fact), ...) : 
 formal argument “at matched by multiple actual arguments

Does anyone know how I might be able to specify the tick marks that I want for 
these particular functions?

Best,

Jacob Berv

Ph.D. Student
Lovette Lab
Cornell Laboratory of Ornithology

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Re: [R-sig-phylo] phytools - evaluating significance of pgls.Ives

2015-03-02 Thread Andrea Berardi
Thank you all very much for the comments! They are so helpful.

Yes, I do only have 8 species, and 3 replicates each. It is not ideal, but it's 
what we have and we have a phylogeny, so I'd like to try some tests 
incorporating phylogeny.

I probably should have added that I plan on running OLS to test each regression 
without the tree. This should give me an idea of the general relationship.

Regarding Liam's comment in pgls.Ives: Is the lower=c(1e-8,1e-8) call of the 
pgls.Ives call the part where it constrains the slope to (almost)zero?

I'll definitely give the MERegPHYSIGv2.m method a try as well, with Tony's 
diagnostic suggestions.

I will also go the LRT route with the data.

Thanks very much again for your help!
Andrea

~~
Andrea Berardi, PhD
Postdoctoral Researcher, Smith Lab
EBIO, University of Colorado-Boulder
andrea.bera...@colorado.edu



On Mar 1, 2015, at 8:42 PM, Liam J. Revell liam.rev...@umb.edu wrote:

 Hi Andrea.
 
 This is not presently implemented, but since this is a likelihood method it 
 would be straightforward to constrain to a slope of zero and then do a LR 
 test. This would be probably be the easiest way to test a hypothesis about 
 the regression.
 
 That being said, as noted in the function documentation, some problems have 
 been reported with the optimization algorithm for this model, which is simple 
 and thus may fail to find the ML solution. Consequently, I would encourage 
 you to look for other implementations of the method so that you can be 
 confident in your result. I'm not aware of one in R at this time.
 
 All the best, Liam
 
 Liam J. Revell, Assistant Professor of Biology
 University of Massachusetts Boston
 web: http://faculty.umb.edu/liam.revell/
 email: liam.rev...@umb.edu
 blog: http://blog.phytools.org
 
 On 3/1/2015 10:31 PM, Andrea Berardi wrote:
 Hi all,
 
 I'm just learning how to do PGLS analyses, and I'm looking for advice on how 
 to evaluate the significance of the regression fit using pgls.Ives in the 
 phytools package. I'm using this function because it incorporates sampling 
 error of species means, and my data has about 3 individuals per species, 
 with 8 species. My goal is to test whether a flower trait predicts the leaf 
 trait, while controlling for shared ancestry. Here is the output from 
 pgls.Ives:
 
 fit - pgls.Ives(Tree, Flower_trait, Leaf_trait)
 fit
 $beta
 [1] 96.3963098  0.1292656
 
 $sig2x
 [1] 22218901073
 
 $sig2y
 [1] 23027587
 
 $a
 [1] -10063.150  -1204.422
 
 $logL
 [1] -158.2337
 
 $convergence
 [1] 0
 
 $message
 [1] CONVERGENCE: REL_REDUCTION_OF_F = FACTR*EPSMCH
 
 I am also running pgls on species averages for the traits using the gls 
 function in nlme and the corBrownian and corMartins functions in ape. But, 
 we are interested in incorporating the within-species variation in our small 
 dataset.
 
 Any suggestions would be welcome!
 
 Thanks for your help,
 Andrea
 
 ~~
 Andrea Berardi, PhD
 Postdoctoral Researcher, Smith Lab
 EBIO, University of Colorado-Boulder
 
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Re: [R-sig-phylo] phytools - evaluating significance of pgls.Ives

2015-03-02 Thread Theodore Garland Jr
Andrea, remember that you can and should also do the OLS models (i.e., 
assuming a star phylogeny) with measurement error considered.  That's in the 
programs that accompany Ives, Midford, and Garland (2007, Syst. Biol. 
56:252–270), and were in the batch I just sent you.

Cheers,
Ted

Theodore Garland, Jr., Professor
Department of Biology
University of California, Riverside
Riverside, CA 92521
Office Phone:  (951) 827-3524
Facsimile:  (951) 827-4286 (not confidential)
Email:  tgarl...@ucr.edu
http://www.biology.ucr.edu/people/faculty/Garland.html
http://scholar.google.com/citations?hl=enuser=iSSbrhwJ

Director, UCR Institute for the Development of Educational Applications

Editor in Chief, Physiological and Biochemical Zoology

Fail Lab: Episode One
http://testtube.com/faillab/zoochosis-episode-one-evolution
http://www.youtube.com/watch?v=c0msBWyTzU0


From: R-sig-phylo [r-sig-phylo-boun...@r-project.org] on behalf of Andrea 
Berardi [andrea.bera...@colorado.edu]
Sent: Monday, March 02, 2015 3:57 PM
To: r-sig-phylo@r-project.org
Cc: Anthony R Ives; Peter Smits
Subject: Re: [R-sig-phylo] phytools - evaluating significance of pgls.Ives

Thank you all very much for the comments! They are so helpful.

Yes, I do only have 8 species, and 3 replicates each. It is not ideal, but it's 
what we have and we have a phylogeny, so I'd like to try some tests 
incorporating phylogeny.

I probably should have added that I plan on running OLS to test each regression 
without the tree. This should give me an idea of the general relationship.

Regarding Liam's comment in pgls.Ives: Is the lower=c(1e-8,1e-8) call of the 
pgls.Ives call the part where it constrains the slope to (almost)zero?

I'll definitely give the MERegPHYSIGv2.m method a try as well, with Tony's 
diagnostic suggestions.

I will also go the LRT route with the data.

Thanks very much again for your help!
Andrea

~~
Andrea Berardi, PhD
Postdoctoral Researcher, Smith Lab
EBIO, University of Colorado-Boulder
andrea.bera...@colorado.edu



On Mar 1, 2015, at 8:42 PM, Liam J. Revell liam.rev...@umb.edu wrote:

 Hi Andrea.

 This is not presently implemented, but since this is a likelihood method it 
 would be straightforward to constrain to a slope of zero and then do a LR 
 test. This would be probably be the easiest way to test a hypothesis about 
 the regression.

 That being said, as noted in the function documentation, some problems have 
 been reported with the optimization algorithm for this model, which is simple 
 and thus may fail to find the ML solution. Consequently, I would encourage 
 you to look for other implementations of the method so that you can be 
 confident in your result. I'm not aware of one in R at this time.

 All the best, Liam

 Liam J. Revell, Assistant Professor of Biology
 University of Massachusetts Boston
 web: http://faculty.umb.edu/liam.revell/
 email: liam.rev...@umb.edu
 blog: http://blog.phytools.org

 On 3/1/2015 10:31 PM, Andrea Berardi wrote:
 Hi all,

 I'm just learning how to do PGLS analyses, and I'm looking for advice on how 
 to evaluate the significance of the regression fit using pgls.Ives in the 
 phytools package. I'm using this function because it incorporates sampling 
 error of species means, and my data has about 3 individuals per species, 
 with 8 species. My goal is to test whether a flower trait predicts the leaf 
 trait, while controlling for shared ancestry. Here is the output from 
 pgls.Ives:

 fit - pgls.Ives(Tree, Flower_trait, Leaf_trait)
 fit
 $beta
 [1] 96.3963098  0.1292656

 $sig2x
 [1] 22218901073

 $sig2y
 [1] 23027587

 $a
 [1] -10063.150  -1204.422

 $logL
 [1] -158.2337

 $convergence
 [1] 0

 $message
 [1] CONVERGENCE: REL_REDUCTION_OF_F = FACTR*EPSMCH

 I am also running pgls on species averages for the traits using the gls 
 function in nlme and the corBrownian and corMartins functions in ape. But, 
 we are interested in incorporating the within-species variation in our small 
 dataset.

 Any suggestions would be welcome!

 Thanks for your help,
 Andrea

 ~~
 Andrea Berardi, PhD
 Postdoctoral Researcher, Smith Lab
 EBIO, University of Colorado-Boulder

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Re: [R-sig-phylo] axisChrono and axisPhylo

2015-03-02 Thread Jacob Berv
Thanks Franz,
I tried modifying the axisChrono function, but when I change the “at=“ argument 
to equal something like “at= c(1,2,3,4,5)” I can get it to list out specific 
tick marks but they are always in increasing order, not reverse order as you 
want with a right facing cladogram. I’m not sure how to reverse the sequence 
within the function.

Jake


Here is the function. 

function (side = 1, unit = Ma, fact = 1, ...) 
{
lastPP - get(last_plot.phylo, envir = .PlotPhyloEnv)
if (lastPP$type %in% c(phylogram, cladogram)) {
if (lastPP$direction %in% c(rightwards, leftwards)) {
x - pretty(lastPP$xx)
if (lastPP$direction == rightwards) 
maxi - max(lastPP$xx)
else {
maxi - min(lastPP$xx)
x - -x
}
}
else {
x - pretty(lastPP$yy)
if (lastPP$direction == upwards) 
maxi - max(lastPP$yy)
else {
maxi - min(lastPP$yy)
x - -x
}
}
}
axis(side = side, at = c(maxi - x), labels = abs(x * fact), 
 ...)
mtext(text = unit, side = side, at = 1.07 * maxi, line = 1, 
  ...)
}





 On Mar 2, 2015, at 5:03 PM, Franz Krah f.k...@mailbox.org wrote:
 
 Hi Jacob,
 
 as far as I can see 'axisPhylo' calculates the at argument of 'axis' 
 itself...
 I think that produces the error if you just put the argument into the 
 'axisPhylo' function. 
 So you have to alter the 'axisPhylo' function so you can define your own 
 'axis' at arguments.
 
 Hope that helps and is correct...
 Best Franz
 
 p.s. that's my first answer here but I feel today is a god day to start 
 (thanks Dave Bapst for encouraging ;-))
 
 Jacob Berv jakeberv.r.sig.ph...@gmail.com hat am 2. März 2015 um 22:38
 geschrieben:
 
 
 Greetings R-sig-phylo,
 This is my first post but happy to join this community
 
 I have been having some trouble with the axisChrono of the phyloch package 
 and
 axisPhylo functions of the ape package that I was hoping someone might be 
 able
 to help me with.
 
 When using either function, the spacing between ticks on the scale is too
 large for the figure I’m trying to generate. I have tried passing variations
 of at=c(1,2,3,4,5), or at=seq(0,10,1) etc, but for either function I get the
 following error:
 
 Error in axis(side = side, at = c(maxi - x), labels = abs(x * fact), ...) : 
 formal argument “at matched by multiple actual arguments
 
 Does anyone know how I might be able to specify the tick marks that I want 
 for
 these particular functions?
 
 Best,
 
 Jacob Berv
 
 Ph.D. Student
 Lovette Lab
 Cornell Laboratory of Ornithology
 
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 MSc. Franz Krah
 Mycology, Phylogenetics, PCM
 http://www.biodiv.wzw.tum.de/index.php?id=18

Jacob Berv

Ph.D. Student
Lovette Lab
Cornell Laboratory of Ornithology

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Re: [R-sig-phylo] The Value of Responding on R-sig-phylo, was: phytools - evaluating significance of pgls.Ives

2015-03-02 Thread Simon Blomberg

Hi Everyone,

I agree with what has been said so far. Tony, don't take my comments to 
heart. Your contribution is most welcome as your opinion is highly 
respected (by me and hopefully by others). Same goes for all the other 
authorities on the list e.g Liam, Joe, Ben, Jarrod, Ted, Marguerite and 
others. I don't contribute much these days due to time constraints, 
which is a shame because I think that lists like this do help people, 
even if particular answers to particular questions are not quite right 
or are incomplete in some sense for the original poster. And I like 
helping people too! Questions can get answers that evolve into 
interesting threads in their own right (like this one, although a bit 
off-topic). Mailing lists like this are more of a group conversation 
rather than a simple do this or don't do that type of thing. I've 
been on lists since the '90s (does anyone remember sci.bio.evolution on 
USENET?). This is one of the best lists I've been on, largely because I 
know that some of the best researchers in the field read the list and 
sometimes respond.


Tony, I know that statistical advice is easier to give when the person 
and data are live right in front of you. That's why I invariably only 
see people by appointment when I give stats advice. I don't like giving 
advice over email and I don't give advice over the phone. (Actually, I 
never answer my phone but that's another story.) It's a bit different on 
the list because other authorities can read the advice an chime in if 
they disagree with anything I say. Hopefully we can all benefit from that.


Keep on posting everybody!

Simon.


On 03/03/15 03:43, Hilmar Lapp wrote:

+100 !!

   -hilmar

On 3/2/15, 11:07 AM, David Bapst wrote:

Off-topic, but I wanted to comment on Anthony's wariness about
commenting on R-sig lists...

Yes, it can certainly be very difficult to give advice that is
tailored specifically to the problem of a particular worker on R-sig
lists, particularly as one can't just tell the other person to open
their data files and show them to you. However, answering a question
on R-sig lists (regardless of whether it is the right answer, but what
answer remains right forever anyway?) records that answer virtually
forever, for future posterity. This means the answer can be found by
any future individuals who encounter this problem, via a simple google
search. Since I first found R-sig-phylo in early 2010 (five years
ago!), I have made almost constant use of the knowledge base contained
with R-sig-phylo's archive. It doesn't mean the information is always
right, or always the best answers for the actual person who asked
originally, but it certainly helps point out the right line of
thinking or the right literature to investigate. StackExchange
discussion archives have become just as valuable (but there appears to
be very little R phylo discussion over there).

It feels like the amount of discussion on the list has dropped off
slowly over the last year, and as phylogenetics in R seems as widely
used as ever, I have often wondered if this reflects that most issues
people may run into are now more easily solved with google searches
leading to the R-sig-phylo archives.

Anyway, I just hope that this element is not forgotten about why I
think replying to question on R-sig-phylo remains a valuable
contribution to our community!

Cheers,
-Dave Bapst



On Mon, Mar 2, 2015 at 7:58 AM, Anthony Ives ari...@wisc.edu wrote:

Simon and Ben,

Of course, sample size of 8 is going to be an issue in almost any

analysis. But sometimes that is all the data there are.

Incidentally, this exchange reminded me that I’m still wary of making

comments on r-sig. If somebody comes into my office, I have the time to
discuss with them their data, so I can learn more about it. Then I feel
I can at least make informed recommendations for analyses — they might
still be badly wrong recommendations, but at least they are informed.
I’m still uncomfortable about making suggestions on r-sig, when I don’t
really have full information, or the time to think. Therefore, the few
comments I’ve made have been very general about methods, rather than
specific about data sets.

I think this is just a matter of me waking up to the 21st century. I

do like the idea of crowdsourcing; I just need to get comfortable with it.

Cheers, Tony


Anthony Ives
Department of Zoology
459 Birge Hall (4th floor, E end of bldg)
UW-Madison
Madison, WI 53706
608-262-1519


On Mar 1, 2015, at 10:53 PM, Simon Blomberg s.blombe...@uq.edu.au

wrote:

Hi Ben,

Yes, you would have to assume constant variance across species to use

N=24. I think that is the only option. But given that biological data
often has a positive mean-variance relationship, again I'm dubious about
the exercise. YMMV, however!

Cheers,

Simon.

Simon Blomberg, BSc (Hons), PhD, MAppStat, AStat.
Senior Lecturer and Consultant Statistician
School of Biological Sciences
The University of Queensland
St. Lucia Queensland 

Re: [R-sig-phylo] axisChrono and axisPhylo

2015-03-02 Thread Santiago Claramunt
Hi Jacob,

What I do is to use the basic axis() function. The trick is to transform the 
scale by subtracting the depth of your tree like this:

axis(1, at=max(branching.times(tree))-0:10, labels=0:10)

Best,

Santiago


On Mar 2, 2015, at 4:38 PM, Jacob Berv jakeberv.r.sig.ph...@gmail.com wrote:

 Greetings R-sig-phylo,
 This is my first post but happy to join this community
 
 I have been having some trouble with the axisChrono of the phyloch package 
 and axisPhylo functions of the ape package that I was hoping someone might be 
 able to help me with.
 
 When using either function, the spacing between ticks on the scale is too 
 large for the figure I’m trying to generate. I have tried passing variations 
 of at=c(1,2,3,4,5), or at=seq(0,10,1) etc, but for either function I get the 
 following error:
 
 Error in axis(side = side, at = c(maxi - x), labels = abs(x * fact), ...) : 
 formal argument “at matched by multiple actual arguments
 
 Does anyone know how I might be able to specify the tick marks that I want 
 for these particular functions?
 
 Best,
 
 Jacob Berv
 
 Ph.D. Student
 Lovette Lab
 Cornell Laboratory of Ornithology
 
 ___
 R-sig-phylo mailing list - R-sig-phylo@r-project.org
 https://stat.ethz.ch/mailman/listinfo/r-sig-phylo
 Searchable archive at http://www.mail-archive.com/r-sig-phylo@r-project.org/



Santiago Claramunt, Ph.D.

Research Associate
Department of Ornithology
American Museum of Natural History

sclaram...@amnh.org
https://sites.google.com/site/sclaramuntuy/

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Re: [R-sig-phylo] axisChrono and axisPhylo

2015-03-02 Thread Jacob Berv
Excellent! Thanks Santiago. 

In case anyone is interested, I ended up using the following three lines to 
generate an axis with labeled and thick tick marks every 10 and thin 
(unlabeled) ticks every 2. There is probably a more elegant way to do this but 
this works:

axis(3, at=max(branching.times(timetree))-seq(0,70,10), 
labels=seq(0,70,10),cex.axis=0.5, line=-0.95, lwd=2)
axis(3, at=max(branching.times(timetree))-seq(0,70,2),cex.axis=0.25, 
line=-0.95, lwd=0.75, labels=FALSE, tick=TRUE)
mtext(text = Ma, side = 3, at = 1.04 * max(branching.times(timetree)), line = 
-1)


 On Mar 2, 2015, at 11:10 PM, Santiago Claramunt sclaram...@amnh.org wrote:
 
 axis(1, at=max(branching.times(tree))-0:10, labels=0:10)

Jacob Berv

Ph.D. Student
Lovette Lab
Cornell Laboratory of Ornithology


[[alternative HTML version deleted]]

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Re: [R-sig-phylo] phytools - evaluating significance of pgls.Ives

2015-03-02 Thread Anthony Ives
Simon and Ben,

Of course, sample size of 8 is going to be an issue in almost any analysis. But 
sometimes that is all the data there are.

Incidentally, this exchange reminded me that I’m still wary of making comments 
on r-sig. If somebody comes into my office, I have the time to discuss with 
them their data, so I can learn more about it. Then I feel I can at least make 
informed recommendations for analyses — they might still be badly wrong 
recommendations, but at least they are informed. I’m still uncomfortable about 
making suggestions on r-sig, when I don’t really have full information, or the 
time to think. Therefore, the few comments I’ve made have been very general 
about methods, rather than specific about data sets.

I think this is just a matter of me waking up to the 21st century. I do like 
the idea of crowdsourcing; I just need to get comfortable with it.

Cheers, Tony


Anthony Ives
Department of Zoology
459 Birge Hall (4th floor, E end of bldg)
UW-Madison
Madison, WI 53706
608-262-1519

 On Mar 1, 2015, at 10:53 PM, Simon Blomberg s.blombe...@uq.edu.au wrote:
 
 Hi Ben,
 
 Yes, you would have to assume constant variance across species to use N=24. I 
 think that is the only option. But given that biological data often has a 
 positive mean-variance relationship, again I'm dubious about the exercise. 
 YMMV, however!
 
 Cheers,
 
 Simon.
 
 Simon Blomberg, BSc (Hons), PhD, MAppStat, AStat.
 Senior Lecturer and Consultant Statistician
 School of Biological Sciences
 The University of Queensland
 St. Lucia Queensland 4072
 Australia
 
 T: +61 7 3365 2506
 email: S.Blomberg1_at_uq.edu.au
 http://www.evolutionarystatistics.org
 
 Policies:
 
 1.  I will NOT analyse your data for you.
 2.  Your deadline is your problem
 
 Basically, I'm not interested in doing research and I never have been. I'm 
 interested in understanding, which is quite a different thing. - David 
 Blackwell
 
 
 From: R-sig-phylo [r-sig-phylo-boun...@r-project.org] on behalf of Ben Bolker 
 [bbol...@gmail.com]
 Sent: Monday, March 02, 2015 2:49 PM
 To: r-sig-phylo@r-project.org
 Subject: Re: [R-sig-phylo] phytools - evaluating significance of pgls.Ives
 
 -BEGIN PGP SIGNED MESSAGE-
 Hash: SHA1
 
 On 15-03-01 11:40 PM, Simon Blomberg wrote:
 Am I missing something? The OP only has 8 species in the data set.
 I wouldn't put much store in fancy PCM modelling based on such a
 small data set. And 3 individuals per species is not enough for a
 good estimate of the within-species variance.
 
 Simon.
 
  Agree wholeheartedly with the first point -- but for the second,
 isn't 24 rather than 8 the relevant number for estimating
 within-species variance (since presumably we are assuming the same
 variance within every species, thus we can effectively pool
 within-species variation \across species for this purpose) ?
 
 
 Simon Blomberg, BSc (Hons), PhD, MAppStat, AStat. Senior Lecturer
 and Consultant Statistician School of Biological Sciences The
 University of Queensland St. Lucia Queensland 4072 Australia
 
 T: +61 7 3365 2506 email: S.Blomberg1_at_uq.edu.au
 http://www.evolutionarystatistics.org
 
 Policies:
 
 1.  I will NOT analyse your data for you. 2.  Your deadline is
 your problem
 
 Basically, I'm not interested in doing research and I never have
 been. I'm interested in understanding, which is quite a different
 thing. - David Blackwell
 
  From: R-sig-phylo
 [r-sig-phylo-boun...@r-project.org] on behalf of Anthony R Ives
 [ari...@wisc.edu] Sent: Monday, March 02, 2015 2:14 PM To: Andrea
 Berardi Cc: r-sig-phylo@r-project.org Subject: Re: [R-sig-phylo]
 phytools - evaluating significance of pgls.Ives
 
 Andrea,
 
 I second Liam’s recommendation to use a LRT.
 
 For measurement error, the latest code I have in matlab is
 MERegPHYSIGv2.m, which does both measurement error and an OU or
 Pagel-lambda transform (see Johnson, M. T. J., A. R. Ives, J.
 Ahern, and J. P. Salminen. 2014. Macroevolution of plant defenses
 against herbivores in the evening primroses. New Phytologist
 203:267-279). Measurement-error models are always going to have
 difficulties at parameter boundaries; for example, if the assumed
 measurement error is large, it can exceed the observed variation in
 the data, which of course causes problems (statistical and
 logical).
 
 In MERegPHYSIGv2.m, I did a round or two of simulated annealing
 first, before polishing the results with a Nelder-Mead optimizer.
 It seems like you could do the same with Liam’s code pretty easily
 by changing the method of optimization (using edit()). Before
 doing this, thought, I would take a careful look at your data and
 your estimates of measurement error. An easy diagnostic is to start
 with 10% of your estimated measurement standard errors and then
 increase slowly to 100%. When I have done this, I’ve been able to
 see problems when parameter values go awry. It is not a fail-safe