Displaying 20 results from an estimated 20000 matches similar to: "PerMANOVA of community data"
2011 Sep 09
2
NMDS plot and Adonis (PerMANOVA) of community composition with presence absence and relative intensity
Hi!
Thanks for providing great help in R-related statistics. Now, however I'm
stuck. I'm not a statistics person but I was recommended to use R to perform
a nmds plot and PerMANOVA of my dataset.
Sample(treatment) in the columns and species (OTU) in the rows. I have 4
treatments (Ambient Temperature, Ambient temperature+Low pH, High
temperature, High temperature+low pH), and I have 16
2012 Feb 02
0
Two-Way PERMANOVA with Repeated Measurements
Hello,
I want to perform a permanova where the first factor called Treatment
has four levels. The second factor involves sampling the same research
plots for four consecutive years, hence the repeated measurements.
I have been able to use the adonis function from the package vegan to
run this analysis.
code below:
TC.perMANOVA.adonis<-adonis(TC.PerMANOVA ~ Treatment*Year,
2013 Jul 10
0
permanova for multivariate repeat measures toxicology data set
Hello,
I would like to use a permanova to analyze my repeated measures,
multivariate data set using the package vegan (adonis function). I
have several explanatory variables and many clinical
biochemistry/hematological response variables (all continuous,
non-normally distributed).
My explanatory variables are:
ID - 29 levels - individual subjects
Treatment - 2 levels
Sex - 2 levels
Time -
2010 Aug 09
0
permanova on MICE object
Hi everyone!
I have data consisting of several response variables and several explanatory
variables. I wish to do a permanova on this using the vegan library and the
adonis() function. However, my data had several missing values in it. In
order to 'fix' this I used the mice() function from the mice library to make
5 imputations for all the missing values. To do analysis on the 5 datasets
2006 Mar 08
1
RES: survival
Dear Thomas,
The head of my dataset
> head(wsuv)
parcel sp time censo treatment
species
1 S8 Poecilanthe effusa ( Hub. ) Ducke. 1 1 1 1
2 S8 Poecilanthe effusa ( Hub. ) Ducke. 1 1 1 1
3 S8 Poecilanthe effusa ( Hub. ) Ducke. 1 1 1 1
4 S8 Poecilanthe effusa ( Hub. ) Ducke. 1 1 1
2010 Mar 16
1
memory failure in adonis function (permanova)
Dear all,
I am trying to get a PERMANOVA with quite large data set. I am reading a lot
about this question, but I do not get the answer about it. Although I know
that the R function is adonis () (vegan package), it does not work:
adonis(Pha.env~SPha, data=Pha, permutations=10)
The error message:
Error: cannot allocate vector of size 334.2 Mb
In addition: Warning messages:
1: In vegdist(lhs,
2010 Apr 16
0
Blocking and Nested ANOVA Design. Am I using the aov() function correctly?
Dear list members,
I am new member and fairly new into R world! I hope what I have is not
beyond the purpose of this list. I did first search for similar
experimental designs without success.
I want to perform an ANOVA analysis using the aov() function. I am not
100% sure that I have it right. If anyone can help me, that will be
greatly appreciated. My design is not balanced for any of the
2009 Jul 23
1
simple lme question
Hi everyone,
I am trying to analyse my data from a small plant experiment (for a meeting tomorrow afternoon) and am a beginner to R so I apologise if this is a very basic question.
I carried out a plant experiment examining plant interactions between two species (A and B) under different watering treatments. I had:
- 7 watering treatments (7 different watering frequencies labelled 1-7)
- 3
2008 May 15
2
mixed effects models with nested factors
Hi everybody,
I am trying to fit a model with the lmer function for mixed effects. I have an experimental design consisting of 5 field plots. Each plot is divided in 12 subplots where the influence of three factors on the growing of tree seedlings is tested: (1) seed (1 = presence; 0 = absence); (2) seedling species (oak holm vs. pine); (3) treatment (three different treatments). In each of
2009 Sep 11
0
R - box design-scatter plot für means/regression/lme?
Dear All!
It's now weeks that I'm going crazy with R, and as I'm a new user I now ask for help (also because I still have only a few days to finish..)...
So shortly I describe you my Experiment in which I was looking for the decomposition of herbivore dung under different treatments:
I made a box design experiment which is structured in the following way:
I collected dung from 2
2013 May 14
1
Post hoc test for GLM with poisson distribution
Hi R-people,
I performed controlled experiments to evaluated the seeds germination of
two palms under four levels of water treatments. I conducted a generalized
linear model (GLM) with a Poisson distribution to verify whether there were
significant differences in the number of seed germination (NS-count
variable) between treatments and species (explanatory variables). Thus, my
model and output
2006 Jun 05
0
CCA Plot
I am a beginner with R and have managed to use vegan to run a CCA on
my data. I am evaluating the habitat relationships of select species
in riparian areas around creeks before and after logging across three
sampling intervals (pre-logging, two-years post-logging,. and 10
years post-logging). I sampled from 18 sites of 3 treatments (n = 6
sites for each treatment). When I plot my
2007 Feb 25
1
nested design in lme, need help with specifying model
Hi,
I wonder if anyone can help me with specifying a right model for my analysis. I am a beginner to lme methods and though have spent already many hours studying from various books an on-line helps, I was unfortunately not able to find a solution to my problem on my own.
Data structure:
I studied escape behavior of three species of a prey to a predator. The prey specimens (many) were in a
2009 May 01
3
adding zeros to dataframe
Greetings,
I am new to R and am hoping to get some tips from experienced R-programmers.
I have a dataset that I've read into R as a dataframe. There are 5 columns: Plot location,species name, a species number code (unique to each species name), abundance, and treatment. There are 272 plots in each treatment, but only the plots in which the species was recorded have an abundance value. For
2005 Sep 22
3
anova on binomial LMER objects
Dear R users,
I have been having problems getting believable estimates from anova on a
model fit from lmer. I get the impression that F is being greatly
underestimated, as can be seen by running the example I have given below.
First an explanation of what I'm trying to do. I am trying to fit a glmm
with binomial errors to some data. The experiment involves 10
shadehouses, divided between
2011 Aug 21
0
Split split plot analysis for unbalanced data using lmer
Hello,
I'm attempting to analyze a split-split plot model, currently using
lmer. My design is similar to that used in Casella's Experimental
Designs Ozone Example (example 5.7, p 197), but I have been unable to
find any coding help for split-split plot models through searches of
several textbooks and the R list serve. I have three treatments of
interest (A,B,C), each with 2 treatment
2011 Mar 28
1
ordination in vegan
Hi all,
I have site data with plant species cover and am looking for trends. I'm
kind of new to this, but have done lots of reading and can't find an answer.
I tried decorana (I know it's been replaced by ca.) and see a trend, but I'm
not sure what it means. Is there a way to get the loadings/eigenvectors of
the axes (like in PCA)? Is there a way to do this with rda() too? How
2010 Jul 18
2
simple loop(?) analysing subsets
Hi All,
I have a large data set with many columns of data. One of these columns is a
species identifier and the remainder are variables such as temperature or
mass. Currently I am carrying out a single regression on subsets of the data
set, e.g. separated data sets with only the data from one species at a time.
I have been searching for a thread that will help me to understand how best
to repeat
2010 Mar 11
0
Multiple comparisons with a mixed effects model
Hello,
I have used R in the past to conduct multiple comparisons on standard linear models, but am a bit confused as to how to go about doing it with a mixed effects model.
I am conducting a bioindication study using carabid beetles in which I have four treatment types (forest harvest types with varying levels of canopy structure retention), and am using canopy closure percent as a covariate in
2009 May 01
0
Apologies: example of data needing zeros-no NA values
Many thanks for your responses. I realize I made the first-time-poster's error of not giving an example of the data. There actually are no NA values, so I'm not simply replacing values in the data frame. So, the number of species (and therefore abundance values) listed in each treatment differs, even though they all have the same number of plots sampled.
Sample_ID Spec_num Species_ID