[R-sig-eco] AdehabitatHR package

2013-12-04 Thread Luciana Cerqueira Ferreira
Hi,


I am working on shark satellite tracking data and I’m trying to use the
function kernelbb from the *adehabitatHR package *to calculate home range.


Some functions from *adehabitatHR *accept the use of a boundary and I was
wondering if there is a way to use a boundary with kernelbb?


Kind Regards,


Luciana Ferreira

-- 
PhD Candidate
The UWA Oceans Institute - Centre for Marine Futures
Australian Institute of Marine Sciences (AIMS)

Mailing address:
Australian Institute of Marine Sciences
The UWA Oceans Institute(MO96)
35 Stirling Highway
Crawley WA,6009
+61 08 6369 4002



-- 
PhD Candidate
The UWA Oceans Institute - Centre for Marine Futures
Australian Institute of Marine Sciences (AIMS)

Mailing address:
Australian Institute of Marine Sciences
The UWA Oceans Institute(MO96)
35 Stirling Highway
Crawley WA,6009
+61 08 6369 4002

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Re: [R-sig-eco] Dealing with overdispersion in mixed model with count data

2013-12-04 Thread Ben Bolker
Bradley Carlson  writes:

> 

> 
> I'd be curious to hear from others if whether there are inherent flaws in
> this approach. I'm not terribly experienced in this area but this was the
> solution I came upon when I dealt with this issue myself.
> 

  There's a bit more information, and a variety of references
on observation-level random effects, at

http://glmm.wikidot.com/faq#overdispersion

  Ben Bolker

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Re: [R-sig-eco] NA error in envfit

2013-12-04 Thread Stephen Sefick

Kendra,

Something is wrong in X or P; find out what the foreign function call is 
 and then you may be able to track down the offending data problem. 
Maybe a logarithm somewhere? This is probably not much help; I don't 
have much experience with envfit.


Stephen

On 12/03/2013 07:06 PM, Mitchell, Kendra wrote:

I'm running a bunch of NMS with vectors fitted (slicing and dicing a large 
dataset in different ways).  I'm suddenly getting an error  from envfit

f.bSBS.org.fit<-envfit(f.bSBS.org.nms, f.bSBS.org.env, permutations=999, 
na.rm=TRUE)

Error in vectorfit(X, P, permutations, strata, choices, w = w, ...) :
   NA/NaN/Inf in foreign function call (arg 1)
In addition: Warning message:
In vectorfit(X, P, permutations, strata, choices, w = w, ...) :
   NAs introduced by coercion

I can plot the NMS and even run ordifit on individual env variables, so can't 
figure out what the problem is.   There aren't any NA/NaN/Inf in either of 
those data that I can find.  I've tried running it without na.rm=TRUE and still 
get the error.  Guidance on how to fix this would be appreciated.

Here's the whole slicing process and str for the data


f.bSBS.org<-f.env$zone.hor=="bSBS.1"
f.bSBS.org.tyc<-f.tyc[f.bSBS.org,f.bSBS.org]
f.bSBS.org.env<-subset(f.env, f.env$zone.hor=="bSBS.1")
f.bSBS.org.nms<-metaMDS(as.dist(f.bSBS.org.tyc), k=3, trymin=50, trymax=250, 
wascores=FALSE)
f.bSBS.org.fit<-envfit(f.bSBS.org.nms, f.bSBS.org.env, permutations=999, 
na.rm=TRUE)


str(f.bSBS.org.env)
'data.frame':63 obs. of  14 variables:
  $ zone : Factor w/ 6 levels "bIDF","bSBS",..: 2 2 2 2 2 2 2 2 2 2 ...
  $ site : Factor w/ 18 levels "A7","A8","A9",..: 12 12 12 12 12 12 12 
12 12 12 ...
  $ om   : Factor w/ 4 levels "0","1","2","3": 2 2 2 3 3 3 2 2 2 3 ...
  $ compaction   : num  1 1 1 1 1 1 1 1 1 1 ...
  $ herbicide: num  0 0 0 0 0 0 0 0 0 0 ...
  $ horizon  : Factor w/ 2 levels "1","2": 1 1 1 1 1 1 1 1 1 1 ...
  $ Water_content: num  50.3 50.3 50.3 50.1 50.1 ...
  $ DNA_ug_g : num  71.2 71.2 71.2 68.6 68.6 ...
  $ C: num  30.5 30.5 30.5 28.4 28.4 ...
  $ N: num  0.863 0.863 0.863 0.81 0.81 ...
  $ pH_H2O   : num  4.63 4.63 4.63 4.49 4.49 ...
  $ CN   : num  35.3 35.3 35.3 35.1 35.1 ...
  $ f.env$zone   : Factor w/ 6 levels "bIDF","bSBS",..: 2 2 2 2 2 2 2 2 2 2 ...
  $ zone.hor : chr  "bSBS.1" "bSBS.1" "bSBS.1" "bSBS.1" ...

str(f.bSBS.org.nms)
List of 35
  $ nobj  : int 63
  $ nfix  : int 0
  $ ndim  : num 3
  $ ndis  : int 1953
  $ ngrp  : int 1
  $ diss  : num [1:1953] 0.00424 0.00437 0.05169 0.07522 0.11039 ...
  $ iidx  : int [1:1953] 12 8 55 56 52 7 56 12 59 52 ...
  $ jidx  : int [1:1953] 7 6 18 55 8 3 18 3 12 49 ...
  $ xinit : num [1:189] 0.654 0.837 0.438 0.105 -0.313 ...
  $ istart: int 1
  $ isform: int 1
  $ ities : int 1
  $ iregn : int 1
  $ iscal : int 1
  $ maxits: int 200
  $ sratmx: num 1
  $ strmin: num 1e-04
  $ sfgrmn: num 1e-07
  $ dist  : num [1:1953] 0.0679 0.0231 0.3598 0.1248 0.1422 ...
  $ dhat  : num [1:1953] 0.0455 0.0455 0.2076 0.2076 0.2076 ...
  $ points: num [1:63, 1:3] -0.1256 0.1224 0.267 0.2374 -0.0427 ...
   ..- attr(*, "dimnames")=List of 2
   .. ..$ : chr [1:63] "LL001" "LL002" "LL003" "LL007" ...
   .. ..$ : chr [1:3] "MDS1" "MDS2" "MDS3"
   ..- attr(*, "centre")= logi TRUE
   ..- attr(*, "pc")= logi TRUE
   ..- attr(*, "halfchange")= logi FALSE
  $ stress: num 0.157
  $ grstress  : num 0.157
  $ iters : int 180
  $ icause: int 3
  $ call  : language metaMDS(comm = as.dist(f.bSBS.org.tyc), k = 3, trymax 
= 250, wascores = FALSE, trymin = 50)
  $ model : chr "global"
  $ distmethod: chr "user supplied"
  $ distcall  : chr "as.dist.default(m = f.bSBS.org.tyc)"
  $ distance  : chr "user supplied"
  $ converged : logi TRUE
  $ tries : num 23
  $ engine: chr "monoMDS"
  $ species   : logi NA
  $ data  : chr "as.dist(f.bSBS.org.tyc)"
  - attr(*, "class")= chr [1:2] "metaMDS" "monoMDS"


--
Kendra Maas Mitchell, Ph.D.
Post Doctoral Research Fellow
University of British Columbia
604-822-5646

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--
Stephen Sefick
**
Auburn University
Biological Sciences
331 Funchess Hall
Auburn, Alabama
36849
**
sas0...@auburn.edu
http://www.auburn.edu/~sas0025
**

Let's not spend our time and resources thinking about things that are so 
little or so large that all they really do for us is puff us up and make 
us feel like gods.  We are mammals, and have not exhausted the annoying 
little problems of being mammals.


-K. Mullis

"A big computer, a compl

Re: [R-sig-eco] Community composition variance partitioning?

2013-12-04 Thread Steve Brewer
Alexandre,

I'll leave it to Sarah to advise you on MRM (and I agree with Jari that
the method you're describing is not going to work). I'll just add that it
is not clear to me why the predictors (even geographic distance) have to
be treated as distances to partition the variance in composition. I'm
assuming the environmental variables were not originally in the form of
euclidean distance matrices and that the raw measurements are available?
As for the geographic distances, if you have lat and long coordinates, why
not treat both lat and long as predictors and do the necessary analyses as
partial distance-based redundancy analyses using capscale? In one analysis
the geographic predictors could be partialled out (with the result
explaining the fraction explained by the environment). In another, the
environmental predictors could be partialled out (with the result
explaining the fraction explained by the geographic distance) and in a
third both geographic and environmental predictors could be considered
with no conditioning covariates (which will give the total variance
explained by both combined).

Best
Steve


J. Stephen Brewer 
Professor 
Department of Biology
PO Box 1848
 University of Mississippi
University, Mississippi 38677-1848
 Brewer web page - http://home.olemiss.edu/~jbrewer/
FAX - 662-915-5144
Phone - 662-915-1077




On 12/4/13 11:50 AM, "Alexandre Fadigas de Souza" 
wrote:

>Dear friends,
>
>   My name is Alexandre and I am trying to analyze a dataset on floristic
>composition of tropical coastal vegetation by means of variance
>partition, according to the outlines of a Tuomisto's recent papers,
>specially
>
>Tuomisto, H., Ruokolainen, L., Ruokolainen, K., 2012. Modelling niche and
>neutral dynamics : on the ecological interpretation of variation
>partitioning results. Ecography (Cop.). 35, 961­971.
>
>   I have a doubt, could you please give your opinion on it?
>
>   We are proceeding a variance partition of the bray-curtis floristic
>distance using as explanatory fractions soil nutrition, topography,
>canopy openess and geographical distances (all as euclidean distance
>matrices).
>
>We are using the MRM function of the ecodist package:
>
>mrm <- MRM(dist(species) ~ dist(soil) + dist(topograph) + dist(light) +
>dist(xy), data=my.data, nperm=1
>
>The idea is that the overall R2 of this multiple regression should be
>used to assess the contributions of the spatial and environmental
>fractions through subtraction :
>
>Three separate multiple regression analyses are needed
>to assess the relative explanatory power of geographical
>and environmental distances. All of these have the same
>response variable (the compositional dissimilarity matrix),
>but each analysis uses a diff erent set of the explanatory
>variables. In these analyses the explanatory variables are:
>(I) the geographical distance matrix only, (II) the environmental
>diff erence matrices only, and (III) all the explanatory
>variables used in (I) or (II). Comparing the R 2 values
>from these three analyses allows partitioning the variance
>of the response dissimilarity matrix to four fractions.
>Fraction A is explained uniquely by the environmental
>diff erence matrices and equals R2 (III) R2 (I). Fraction B
>is explained jointly by the environmental and geographical
>distances and equals R2 (I) R2 (II) R2 (III). Fraction C
>is explained uniquely by geographical distances and
>equals R2 (III) R2 (II). Fraction D is unexplained by the
>available environmental and geographical dissimilarity
>matrices and equals 100% R2 (III) (throughout the present
>paper, R2 values are expressed as percentages rather
>than proportions). [Tuomisto et al. 2012]
>
>The problem is that the R2 of the overall model (containing all the
>explanatory variables) is smaller than most of the R2 of models
>containing each of the explanatory matrices. So it seems not possible to
>proceed with the approach proposed.
>
>
>Sincerely,
>
>Alexandre
>
>Dr. Alexandre F. Souza
>Professor Adjunto II Departamento de Botanica, Ecologia e Zoologia
>Universidade Federal do Rio Grande do Norte (UFRN)
>http://www.docente.ufrn.br/alexsouza  Curriculo:
>lattes.cnpq.br/7844758818522706
>
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Re: [R-sig-eco] Community composition variance partitioning?

2013-12-04 Thread Jari Oksanen
Hi,

Not only odd, but impossible. If you have a model y ~ x1, and you *add* a new 
explanatory variable, you cannot get worse in raw R2. You can get worse in 
adjusted R2. You can also get worse if you add variables to a matrix for which 
you calculate distances. So dist(y) ~ dist([x1]) can have higher R2 than 
dist(y) ~ dist([x1,x2]) -- bioenv is based on this.

Cheers, Jari Oksanen

Sent from my iPad

> On 4.12.2013, at 20.19, "Sarah Goslee"  wrote:
> 
> Hi,
> 
> That seems a bit odd: can you provide a reproducible example, off-list
> if necessary?
> 
> Sarah
> 
> 
> 
> On Wed, Dec 4, 2013 at 12:50 PM, Alexandre Fadigas de Souza
>  wrote:
>> Dear friends,
>> 
>>   My name is Alexandre and I am trying to analyze a dataset on floristic 
>> composition of tropical coastal vegetation by means of variance partition, 
>> according to the outlines of a Tuomisto's recent papers, specially
>> 
>> Tuomisto, H., Ruokolainen, L., Ruokolainen, K., 2012. Modelling niche and 
>> neutral dynamics : on the ecological interpretation of variation 
>> partitioning results. Ecography (Cop.). 35, 961–971.
>> 
>>   I have a doubt, could you please give your opinion on it?
>> 
>>   We are proceeding a variance partition of the bray-curtis floristic 
>> distance using as explanatory fractions soil nutrition, topography, canopy 
>> openess and geographical distances (all as euclidean distance matrices).
>> 
>> We are using the MRM function of the ecodist package:
>> 
>> mrm <- MRM(dist(species) ~ dist(soil) + dist(topograph) + dist(light) + 
>> dist(xy), data=my.data, nperm=1
>> 
>> The idea is that the overall R2 of this multiple regression should be used 
>> to assess the contributions of the spatial and environmental fractions 
>> through subtraction :
>> 
>> Three separate multiple regression analyses are needed
>> to assess the relative explanatory power of geographical
>> and environmental distances. All of these have the same
>> response variable (the compositional dissimilarity matrix),
>> but each analysis uses a diff erent set of the explanatory
>> variables. In these analyses the explanatory variables are:
>> (I) the geographical distance matrix only, (II) the environmental
>> diff erence matrices only, and (III) all the explanatory
>> variables used in (I) or (II). Comparing the R 2 values
>> from these three analyses allows partitioning the variance
>> of the response dissimilarity matrix to four fractions.
>> Fraction A is explained uniquely by the environmental
>> diff erence matrices and equals R2 (III) R2 (I). Fraction B
>> is explained jointly by the environmental and geographical
>> distances and equals R2 (I) R2 (II) R2 (III). Fraction C
>> is explained uniquely by geographical distances and
>> equals R2 (III) R2 (II). Fraction D is unexplained by the
>> available environmental and geographical dissimilarity
>> matrices and equals 100% R2 (III) (throughout the present
>> paper, R2 values are expressed as percentages rather
>> than proportions). [Tuomisto et al. 2012]
>> 
>> The problem is that the R2 of the overall model (containing all the 
>> explanatory variables) is smaller than most of the R2 of models containing 
>> each of the explanatory matrices. So it seems not possible to proceed with 
>> the approach proposed.
>> 
>> 
>>Sincerely,
>> 
>>Alexandre
>> 
>> Dr. Alexandre F. Souza
>> Professor Adjunto II Departamento de Botanica, Ecologia e Zoologia  
>> Universidade Federal do Rio Grande do Norte (UFRN)  
>> http://www.docente.ufrn.br/alexsouza  Curriculo: 
>> lattes.cnpq.br/7844758818522706
>> 
>> ___
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>> R-sig-ecology@r-project.org
>> https://stat.ethz.ch/mailman/listinfo/r-sig-ecology
> 
> 
> 
> -- 
> Sarah Goslee
> http://www.stringpage.com
> http://www.sarahgoslee.com
> http://www.functionaldiversity.org
> 
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Re: [R-sig-eco] Community composition variance partitioning?

2013-12-04 Thread Sarah Goslee
Hi,

That seems a bit odd: can you provide a reproducible example, off-list
if necessary?

Sarah



On Wed, Dec 4, 2013 at 12:50 PM, Alexandre Fadigas de Souza
 wrote:
> Dear friends,
>
>My name is Alexandre and I am trying to analyze a dataset on floristic 
> composition of tropical coastal vegetation by means of variance partition, 
> according to the outlines of a Tuomisto's recent papers, specially
>
> Tuomisto, H., Ruokolainen, L., Ruokolainen, K., 2012. Modelling niche and 
> neutral dynamics : on the ecological interpretation of variation partitioning 
> results. Ecography (Cop.). 35, 961–971.
>
>I have a doubt, could you please give your opinion on it?
>
>We are proceeding a variance partition of the bray-curtis floristic 
> distance using as explanatory fractions soil nutrition, topography, canopy 
> openess and geographical distances (all as euclidean distance matrices).
>
> We are using the MRM function of the ecodist package:
>
> mrm <- MRM(dist(species) ~ dist(soil) + dist(topograph) + dist(light) + 
> dist(xy), data=my.data, nperm=1
>
> The idea is that the overall R2 of this multiple regression should be used to 
> assess the contributions of the spatial and environmental fractions through 
> subtraction :
>
> Three separate multiple regression analyses are needed
> to assess the relative explanatory power of geographical
> and environmental distances. All of these have the same
> response variable (the compositional dissimilarity matrix),
> but each analysis uses a diff erent set of the explanatory
> variables. In these analyses the explanatory variables are:
> (I) the geographical distance matrix only, (II) the environmental
> diff erence matrices only, and (III) all the explanatory
> variables used in (I) or (II). Comparing the R 2 values
> from these three analyses allows partitioning the variance
> of the response dissimilarity matrix to four fractions.
> Fraction A is explained uniquely by the environmental
> diff erence matrices and equals R2 (III) R2 (I). Fraction B
> is explained jointly by the environmental and geographical
> distances and equals R2 (I) R2 (II) R2 (III). Fraction C
> is explained uniquely by geographical distances and
> equals R2 (III) R2 (II). Fraction D is unexplained by the
> available environmental and geographical dissimilarity
> matrices and equals 100% R2 (III) (throughout the present
> paper, R2 values are expressed as percentages rather
> than proportions). [Tuomisto et al. 2012]
>
> The problem is that the R2 of the overall model (containing all the 
> explanatory variables) is smaller than most of the R2 of models containing 
> each of the explanatory matrices. So it seems not possible to proceed with 
> the approach proposed.
>
>
> Sincerely,
>
> Alexandre
>
> Dr. Alexandre F. Souza
> Professor Adjunto II Departamento de Botanica, Ecologia e Zoologia  
> Universidade Federal do Rio Grande do Norte (UFRN)  
> http://www.docente.ufrn.br/alexsouza  Curriculo: 
> lattes.cnpq.br/7844758818522706
>
> ___
> R-sig-ecology mailing list
> R-sig-ecology@r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-ecology



-- 
Sarah Goslee
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http://www.sarahgoslee.com
http://www.functionaldiversity.org

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[R-sig-eco] Community composition variance partitioning?

2013-12-04 Thread Alexandre Fadigas de Souza
Dear friends,

   My name is Alexandre and I am trying to analyze a dataset on floristic 
composition of tropical coastal vegetation by means of variance partition, 
according to the outlines of a Tuomisto's recent papers, specially

Tuomisto, H., Ruokolainen, L., Ruokolainen, K., 2012. Modelling niche and 
neutral dynamics : on the ecological interpretation of variation partitioning 
results. Ecography (Cop.). 35, 961–971.

   I have a doubt, could you please give your opinion on it?

   We are proceeding a variance partition of the bray-curtis floristic distance 
using as explanatory fractions soil nutrition, topography, canopy openess and 
geographical distances (all as euclidean distance matrices).

We are using the MRM function of the ecodist package:

mrm <- MRM(dist(species) ~ dist(soil) + dist(topograph) + dist(light) + 
dist(xy), data=my.data, nperm=1

The idea is that the overall R2 of this multiple regression should be used to 
assess the contributions of the spatial and environmental fractions through 
subtraction :

Three separate multiple regression analyses are needed
to assess the relative explanatory power of geographical
and environmental distances. All of these have the same
response variable (the compositional dissimilarity matrix),
but each analysis uses a diff erent set of the explanatory
variables. In these analyses the explanatory variables are:
(I) the geographical distance matrix only, (II) the environmental
diff erence matrices only, and (III) all the explanatory
variables used in (I) or (II). Comparing the R 2 values
from these three analyses allows partitioning the variance
of the response dissimilarity matrix to four fractions.
Fraction A is explained uniquely by the environmental
diff erence matrices and equals R2 (III) R2 (I). Fraction B
is explained jointly by the environmental and geographical
distances and equals R2 (I) R2 (II) R2 (III). Fraction C
is explained uniquely by geographical distances and
equals R2 (III) R2 (II). Fraction D is unexplained by the
available environmental and geographical dissimilarity
matrices and equals 100% R2 (III) (throughout the present
paper, R2 values are expressed as percentages rather
than proportions). [Tuomisto et al. 2012]

The problem is that the R2 of the overall model (containing all the explanatory 
variables) is smaller than most of the R2 of models containing each of the 
explanatory matrices. So it seems not possible to proceed with the approach 
proposed.


Sincerely,

Alexandre

Dr. Alexandre F. Souza 
Professor Adjunto II Departamento de Botanica, Ecologia e Zoologia  
Universidade Federal do Rio Grande do Norte (UFRN)  
http://www.docente.ufrn.br/alexsouza  Curriculo: lattes.cnpq.br/7844758818522706

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Re: [R-sig-eco] beta regression error

2013-12-04 Thread Attila Lengyel
Thank you, Peter!

Attila


2013/12/3 Peter Solymos 

> Attila,
>
> See paper and R code by Millar et al. 2011 for a solution based on 'glm':
> http://www.esapubs.org/archive///ecol/E092/146/
>
> Peter
>
> --
> Péter Sólymos, Dept Biol Sci, Univ Alberta, T6G 2E9, Canada AB
> soly...@ualberta.ca, Ph 780.492.8534, http://psolymos.github.com
> Alberta Biodiversity Monitoring Institute, http://www.abmi.ca
> Boreal Avian Modelling Project, http://www.borealbirds.ca
>
>
> On Tue, Dec 3, 2013 at 9:23 AM, Attila Lengyel wrote:
>
>> Dear All,
>>
>> I have a problem with 'betareg' function of 'betareg' package, would you,
>> please, help me? I am trying to model compositional similarity on range
>> (0;
>> 1) between pairs of sample units as a function of pairwise geographical
>> distances, and I often get an error message like this:
>>
>> "Error in chol.default(K) :
>>   the leading minor of order 3 is not positive definite
>> In addition: Warning message:
>> In sqrt(wpp) : NaNs produced
>> Error in chol.default(K) :
>>   the leading minor of order 3 is not positive definite
>> In addition: Warning messages:
>> 1: In betareg.fit(X, Y, Z, weights, offset, link, link.phi, type,
>> control) :
>>   failed to invert the information matrix: iteration stopped prematurely
>> 2: In sqrt(wpp) : NaNs produced"
>>
>> The problem occurs with any link function. I read that this error is
>> caused
>> when my matrix is not positive definite. But how should I avoid this if
>> these are the data I have?
>>
>> Thank you and best regards,
>>
>> Attila Lengyel
>>
>> [[alternative HTML version deleted]]
>>
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>>
>>
>

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