search for: invertebr

Dear All, I am using a Procrustes analysis to compare two NMDS ordinations for the same set of sites. One ordination is based on fish data, the other is based on invertebrate data. Ordinations were derived using metaMDS() from the {vegan} library as follows: fish.mds<-metaMDS(fish.data, distance="bray", k=3, trymax=100, wascores=TRUE, trace=TRUE, zero="add") invert.mds<-metaMDS(bugcal.a, distance="bray", k=3, trymax=100, wascores...

Hi! I wish to know if there is any R forum which is meant only for Statistics? I mean where we can clarify our statistics doubts and seek knowledge. I know there are lot many books and internet sites, but 'R forum' has altogether different standard and very high level and one can learn a lot from them. Regards Vincy [[alternative HTML version deleted]]

Hi everybody, I used randomForest to regress invertebrates abundances in least impaired river reaches from some environmental parameters. Then I used these models to predict invertebrates abundances in impaired reaches. Now I would like to model the deviation (observation - prediction) with a set of chemical parameters to see if the deviations from pr...

Greetings How do I do this in R? Checking the Cran site produces a bewildering array of packages that I can't seem to find to load. Surely the main program has this function? Cheers Kurt *************************************************************** Kurt Lewis Helf, Ph.D. Invertebrate Ecologist National Park Service Cumberland Piedmont Network P.O. Box 8 Mammoth Cave, KY 42259 Ph: 270-758-2163 Lab: 270-758-2151 Fax: 270-758-2609 **************************************************************** Science, in constantly seeking real explanations, reveals the true majesty of our wo...

...he two highest maxima in a trimodal distribution? Thanks for any help Rob Knell School of Biological and Chemical Sciences Queen Mary, University of London 'Phone +44 (0)20 7882 7720 Skype Rob Knell Research: http://www.qmw.ac.uk/~ugbt794 Giant edible caterpillars: http://www.mopane.org Invertebrate macro photography: http://web.mac.com/rknell/iWeb/Bugsite "The truth is that they have no clue why the beetles had horns, it's the researchers who have sex on the brain and everything has to have a sexual explanation. And this is reasearch?!" Correspondent known as FairOpini...

...lot(c(0,1),stationmean,xaxt='n',type="b",pch=20,col="green3", main="Foxtail Seeds Remaining vs. Station Type", ylab="Mean Number Foxtail Seeds Remaining", xlab="Station Type",ylim=c(10,20),xlim=c(-.25,1.25)) axis(1,at=c(0,1),labels=c("Invertebrate Only","Open Access")) # Poster figure 3 meantime=22.1 meancumrainfall=.4837 meanavelowt=35.4920071 meanavehight=55.3242738 meanvegcover=81.1729167 pred.veg = 33.3160 + -.2439*meantime - .8409*(.5) + 8.6833*(.5) + .5427*(meancumrainfall)-.3087*(meanavehight) + .01087*(seq(0,1...

..., 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L, 2L, 3L, 5L, 1L, 4L), .Label = c("Bird", "Fish", "Invertebrate", "Other", "Reptile"), class = "factor"), Size = structure(c(2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 1L,...

Dear R, I am using stepwise multiple glm to select a subset of variables using the step command. My question is how do you calculate the percentage variance for each parameter in the reduced model. An example of my code thus far is, fit<-glm(Abalone~offset(Area)+Sessile invertebrates+Bare rock+ NCA + Encrusting red algae, family = poisson ()) step(fit) fit1<-glm(Abalone~offset(Area)+Bare rock+NCA+Encrusting red algae, family=poisson()) Thanks in advance Beth Strain _________________________________________________________________ What are you waiting for? Join Laval...

Hello! I am working on a manuscript on sexual dimorphism in an aquatic invertebrate, where we have estimated sexual dimorphism (SD) for 7 different traits in four populations (a total of 28 SD-estimates). We have used the following formula for estimating SD: 100 * (mean male trait value - mean female trait value)/overall trait mean). Then, we have used these SD-estimates to pe...

Greetings I am attempting to plot observations of a cave aquatic invertebrate dating from 1901-2004. I can come up with a nice lattice plot of the eight sites from which I have data easily enough. However, I'd like to be able to highlight the 0 observations on the plots, i.e., attempts to find it at the site were unsuccessful. I'd like to be able to highlight t...

Dear list, I performed a multivariate analysis on freshwater invertebrates data. So I obtained coordinates of my samples on the axes defining the first factorial plane (F1 and F2). I would like to see if the positions on my factorial plan could be linked to levels of impairment ('low' vs 'significant') for several water quality pressure categories and...

..., 1168L, 1169L, 1170L), class = "data.frame") # ---------- Diet Analysis ENDS-------------------- # -----------Agresti's (2002) alligator example BEGINS------------ # The measured response is the category of primary food choice of 219 alligators caught # in four Florida lakes (fish, invertebrate, reptile, bird, other). The explanatory variables # are categorical: L = lake of capture, G =gender, S = size ( . 2.3 m, > 2.3 m) # After performing model selection, Agresti concludes that the example can be simpified by collapsing over gender # Therefore, the model is (FoodChoice ~ Lake + Si...