similar to: matrix creation

Hello, I am trying to use the projection.matrix( ) function and am following the example given. I have my data formatted very similar to the test.census example. > str(AsMi05mat) `data.frame': 1854 obs. of 6 variables: $ Tag : num 501 502 503 504 505 506 507 508 509 510 ... $ Year : int 1995 1995 1995 1995 1995 1995 1995 1995 1995 1995 ... $ Length : num 34

Dear All, I am analysing a dataset on levels of herbivory in seedlings in an experimental setup in a rainforest. I have seven classes/categories of seedling damage/herbivory that I want to analyse, modelling each separately. There are twenty maternal trees, with eight groups of seedlings around each. Each tree has a TreeID, which I use as the random effect (blocking factor). There are two

Hi all, I am trying to set up a simple path analysis in the SEM package, but I am having some trouble. I keep getting the following error message or something similar with my model, and I'm not sure what I'm doing wrong: Error in solve.default(C) : system is computationally singular: reciprocal condition number = 2.2449e-20 In addition: Warning message: In sem.default(ram = ram, S = S,

Dear members of the R help list, I want to do a hierarchical glm with binomial family but am unsure about how to write the syntax which involves nesting. I want to test whether the risk of being attacked by Herbivores for Meadowsweet plants is significantly dependent on the Distance to heterospecific source plants. Dependent variable = Herbivory (yes/no) Explanatory continuous variable =

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 Seed reduction due to herbivory (SR) = continuous explanatory variable Herbivore species (HS, 2 levels) = categorical explanatory variable Population (Pop, 24 levels) =

Hello, I'm trying to compare the allozyme data from two taxa. I have several columns of data (19 loci) for each species. I want to do a Mann-Whitney U-test or the wilcox.test (two sample Wilcoxon). When I try to run my code (the first two columns are 1:name of the species, 2:name of individual) I get the error message: "Error in wilcox.test.default(CaScSc, CaScCo, alternative

Hello, I'm in need of running a PVA and want to load {popbio}. However, I can't find it. I can't see where or how to load it. I have added repositories and changed the CRAN mirror site. I see {polynom} and {popgen} but no {popbio} between. What am I doing wrong? Thanks, Michelle [[alternative HTML version deleted]]

Hello, I am creating a 3D scatter plot with the cloud function. I ask it to group my rows by a "Treatment" column (there are 4 different groups). I need to know which points in the plot correspond to which rows (which treatment). By default it assigns pchs and cols to each group. When I try to define the colors or point shapes it seems to use the first color and pch for both the first

Hello, We are trying to find a function to compute "stress" in our multidimensional scaling analysis of a dissimilarity matrix. We've used "dist()" to create the matrix and "cmdscale()" for the scaling. In order to determine the number of dimensions we would like to plot stress vs. dimensions. However, we cannot find a pre-made command. It seems that other

Hello, I am trying to plot lines in 3 dimensions from a multiple linear model to illustrate the interaction of two of the explanatory variables. I'm trying to use the cloud function (though I'm open to a different function if an easier one exists). I keep getting the error message: Error in cloud(lmPeHa061201, data = PeHa061201, cex = 0.8, main = "Table 99: PeHa", :

Hello, I am running the plot from countCDFxt (popbio). I would like to report the y-axis as a percent instead of the log scale (e^01...). I can add an axis with axis(2, 0:1, line =2) but I'm having trouble understanding how to assign the tic marks (with 'at ='). I'd like to tell it to make tics with the percent value (or decimal if that's my only option) at the equivalent of

I am trying to make some plots for a poster. Each one needs to be 6 inches by inches. Right now the fonts are too small and the plots don't read well on my poster. I am pretty much an R newbie and I can't figure out how to change the fonts. It would also be nice to know how to specify the size of the plot and maybe how to save the plots as jpeg files. Any help would be much appreciated! I

Dear all, I'm attempting to use a piecewise regression to model the trajectory of reproductive traits with age in a longitudinal data set using a mixed model framework. The aim is to find three slopes and two points- the slope from low performance in early age to a point of high performance in middle age, the slope (may be 0) of the plateau from the start of high performance to the

I'm trying to learn statistics and R at the same time. I have an undergraduate science degree and one year of calculus (30 years ago), but never took a stats course. I hope to take some stats courses in the next year, but thought I would start to see how much I could teach myself. I work for an organization that analyses behavior change communication programs regarding HIV/AIDS and

Dear all, I have a undirected network (g), representing all the sexual relationships that ever existed in a model community. I also have a directed edgelist (e) which is a subset of the edgelist of g. e represents the transmission pathway of HIV. Now I would like to superimpose the picture of the sexual relationships with arrows in a different colour, to indicate where in the network HIV was

I'm working with a linear model with four factors as explicatory variables, being all of them significally (e.g. y ~ a + b + c + d). I thought that the residuals of a linear model keep the variance not explained by the model, so if I use my model with just three factors (y ~ a + b + c) and keep the residuals is expected that in a new model with the residuals as dependent variable and the four

Hi all, I am very new to R and this might be a simple question but I have looked everywhere you suggest before writing to you. I am trying to change font type from san-serif to a serif (Times New Romans) on all labels and axis of my boxplot. I have used this function in other plots before, e.g.: plot(residuals~lnlifespan, data=mydata, pch=psymb, font=6, xlab="ln reproductive

Dear list, i'm a new R user, so I apologize if the topic is already being addressed by some other user. I'm trying to determine if the reproductive success of a species of bird is related to a list of covariates. These are the covariates: ? elev: elevation of nest (meters) ? seadist: distance from the sea (meters) ? meanterranova: records of temperature ? minpengS1: records

Often, when exploring a dataset, I'd like to plot several very different Y variables against the same X variable, in panels stacked one over the other. Is there an easy way to do this? I'd like to achieve an elegant look similar to the look achieved by lattice in conditioned plots--for instance no space between panels. But unlike in straightforward conditioned plot, each panel may be on a

Hi, I need to analyze the influences of several factors on a variable that is a measure of fecundity, consisting of 73 observations ranging from 0 to 5. The variable is continuous and highly positive skewed, none of the typical transformations was able to normalize the data. Thus, I was thinking in analyzing these data using a generalized linear model where I can specify a distribution other than