similar to: denoting post-hoc test differences using letters

I am trying to tweak how my categorical x-axis labels are formatted in my bar graph. Specifically, I would like to a) decrease the spacing between lines (e.g. spacing between Dialium and guianensis) b) right justify the text and c) have each species name align with the center of the corresponding bar graph. A simplified version of my code thus far is as follows. I am using RStudio v.

I am making a barplot using barplot2 from gplots where each bar represents a specific tree species. I have formatted the species names on the x-axis so that the genus name is above the species name and have then rotated the labels 45 degrees to save room. This is my code: >columncolor<-c("grey20", "grey20", "grey20", "grey70",

I am making a barplot using barplot2 from gplots and would like to format the names of my categorical variables (tree species) on the x- axis so that the genus name is above the species name (to save room). My code so far is: speciesnames<-c("Dialium guianensis", "Inga alba", "Tachigali versicolor", "Brosimum utile", "Caryocar

Hi, I have a data frame with columns as follows: tree species (independent variable) and several dependent variables (e.g. carbon, nitrogen, phosphorus). Each row represents one tree sample. Some tree samples are unique species in the data frame while other species were replicated (i.e. rows 1,2,3 may be identical for the "tree species" column but have different values for the

I am having problem loading packages in the newest version of R (2.13.0) on my Mac. I have tried to install various packages (e.g. lawstat, Rcmdr, car) and load them using the Package Installer and Package Manager menu options but I get the follow error: > library(lawstat) Loading required package: mvtnorm Error: package 'mvtnorm' could not be loaded In addition: Warning

Hi, I was trying to figure out how to do post-hoc tests for Two Way ANOVAs and found the following 2 approaches: a. Do pairwise t-tests (bonferroni corrected) if one finds significance with the ANOVA. Link- http://rtutorialseries.blogspot.com/2011/01/r-tutorial-series-two-way-anova-with.html b. Do TukeyHSD on an aov model Link-

Quick question, as I attempt to learn R. For post-hoc tests 1) Is there an easy function that will take, say the results of tukeyHSD and create a grouping table. e.g., if I have treatments 1, 2, and 3, with 1 and 2 being statistically the same and 3 being different from both Group Treatment A 1 A 2 B 3 2) I've been stumbling over the proper syntax for simple effects for a tukeyHSD

Hi, is there a specific/appropriate function/package to perform post hoc tests when running a two way repeated measures anova? I'm looking for something that will be equivalent to the 'TukeyHSD()' for between subjects anova (with 'aov()'). For one way repeated measures anova, the 'pairwise.t.test()' function seems to work correctly but the results are questionable for

Greetings all, I've done some ANOVAs and have found significant effects across my groups, so now I have to do some post-hoc tests to ascertain which of the groups is driving the significant effect. Usually one would do something like a Newman-Keuls or Scheffe test to get at this but based on googling and browsing through the r-help archives R doesn't support these and they seem to be

Hello everyone, Like a lot of people, I have been looking for functions in R doing ANOVA (ok) and performing multicomparisons (like Student-Newman-Keuls, etc.). As I have been a little bit disappointed, I have bee looking through the net for such "open source" softwares. I found one in: http://www.statpages.org/miller/openstat/OS4.html I have begun to use it, and it seems good and

Hello all R-helpers, I've performed an experiment to test for differential effects of elevated temperatures on three different groups of corals. I'm currently performing a cox proportional hazards regression with censoring on the survivorship (days to mortality) of each individual in the experiment with two factors: Temperature Treatment (2 levels: ambient and elevated) and

Listmates, I have had a few boxes where the 'matchname' message is filling my syslog with one new message ever ~40 seconds or so. No performance problems, just the log annoyance. An example of the messages are: Jan 11 13:43:03 nemesis smbd[2246]: [2010/01/11 13:43:03, 0] lib/util_sock.c:1685(get_peer_name) Jan 11 13:43:03 nemesis smbd[2246]: Matchname failed on Adrienne-PC.rbpllc.com

This is only partly an R question, but this seems a good place to ask. Like many, if not most, statistics programs, R has no post hoc tests for Kruskal Wallis or Friedman, and as far as I can make out they are not available in any of the R packages. I would be grateful if someone could point me in the right direction if I am wrong. As I said this is not uncommon. Parametric Anova procedures

dear r community... it loks like i won't be able to reach homogenity of variance for my dataset, so i end up with welch anova instead of regular anova. documentation on this test is rather scarce, so maybe someone here can enlighten me a bit: - do i understand that no two-way implementation of the welch anova has been developed yet? - is there a post-hoc test for welch anovas implemented in

To all, I'm working with code below to produce a map with station data plotted in points, but right now I'm having trouble with the mapping portion of this code states <- data.frame(map("state", plot=FALSE,xlim= c(-85,-75),ylim=c(33,37))[c("x","y")]) usamap<- ggplot(states)+geom_path(aes(x,y)) usamap When I plot this the problem is that the bounds of

Hello, I am trying to determine the most appropriate way to run post-hoc comparisons on my lme model. I had originally planned to use Tukey HSD method as I am interested in all possible comparisons between my treatment levels. TukeyHSD, however, does not work with lme. The only other code that I was able to find, and which also seems to be widely used, is glht specified with Tukey:

Greetings! I'm having an issue with the windrose produced by the windrose function from the circular package. For our weather stations in North Carolina I'm helping with a script which takes hourly wind speed and direction data to create windroses for our end users. One of the stations in the mountains frequently reaches wind speed of 40 to 60 mph and in storms can reach wind speed over

Dear R people, I have a couple of questions about post-doc analyses for 2 by 2 within subjects ANOVA. I conducted a psycholinguistic study that combined a 2 by 2 design and a latin square design. Specifically, I had 32 items each of which generated 4 conditions. Participants saw each of the 32 items only once: 8 in Condition A, 8 in B, 8 in C, and 8 in D. The table below serves as an example.

Hello: I am trying to use optim() to estimate the maximum likelihood of a function a*x^b = y. Unfortunately, I always get the error, that there is no default value for b. Could you give me an example, on how to correctly optimize this function with input data x<-c(1,3,11,14). Thanks a lot, Adrienne -- *********************************************************************** Adrienne

Hello everybody, I use the sweetpotato database included in R package: data(sweetpotato) This dataset contains two variables: yield(continous variable) and virus(factor variable). Due to Levene test is significant I cannot assume homogeneity of variances and I apply Welch test in R instead of one-way ANOVA followed by Tukey posthoc. Nevertheless, the problems come from when I apply posthoc