similar to: discriminant analysis

Hello everyone, I am totally new to the R program. I have had a look at some pdf documents that I downloaded and that explain how to do many things in R; however, I still cannot figure out how to do what I want to do, which is to perform Discriminant Correspondence Analysis on a rectangular matrix of data that I have in an Excel file. I know R users frown upon Excel and recommend converting Excel

I am trying to use the function gl (generate levels), and would like to make levels with different number of replications. Does anyone know how to generate different number of replications in each level? Something like: [1] Site1 Site1 Site1 Site1 Site1 Site1 Site1 [8] Site2 Site2 Site2 Site2 Site2 Thanks in advance -- Rog?rio R. Silva MZUSP http://www.mz.usp.br Linux/Debian User # 354364

Hello R list, I'm looking to do some stepwise discriminant function analysis (DFA) based on the minimization of Wilks' lambda in R to end up with a composite signature (of metals "Al","Sb","Bi","Cr","Ba") capable of discriminating 100% of the source factors (LANDUSE: "A","B","C"). The Wilks' lambda

Dear all, I am trying to extract rows from a data.frame based on the rowSums != 0. I want to preserve rownames in the first column in the subset. Does anyone know how to extract all species that don't have rowSums equal to zero? Here it is: # dataset x <- data.frame( species=c("sp.1","sp.2","sp.3","sp.4"), site1=c(2,3,0,0), site2=c(0,0,0,0),

Hi all, is it possible to do stepwise discriminant analysis (linear amnd non-linear) in R? If yes- which package does it|? Thanks Janine -------------------------------------------- "El gesto y la palabra son el pensamiento del hombre" Isabel Allende Janine Illian lecturer in statistics SIMBIOS School of Computing University of Abertay Dundee Bell Street Dundee, DD1 1HG Scotland,

Dear all As part of an ongoing study on the ecomorphology of ant communities, I have obtained a matrix with 156 row (species) and 20 columns (several measurements of body shape) for 4 localities. For each community, I calculated a matrix of Euclidean distances between all pairs of species. From this matrix, I extracted two measures of community structure: i) I identified the distance from a

I don't understand which is the problem Could you help me please? Thanks in advance Marta > str(data_indiciN2) 'data.frame': 200 obs. of 36 variables: $ gruppo: Factor w/ 2 levels "0","1": 2 2 2 2 2 2 2 2 2 2 ... $ I001N2: num 19.32 8.22 28.35 7.24 14.7 ... $ I002N2: num 2.92 2.54 0.11 1.6 7.12 ... $ I003N2: num -22.362 -0.222 -19.291

Hello, I not have attached in this e-mail the zipped list of matrices I am using because it has 1 meg once zipped and anyway we cannot send attached files on r-help mailling list. First, after running the code that is written bellow, I realized that the printout of dudi.pca gives me for both of my matrices $cw length that are unequal to either respective $rank or $eig lengths. Is that

Hello, I'm a new user of R, and unsure of why I'm getting an error reading external files on my Mac OS 8.6 machine. I've read through posts that would seem related (and 'R Import/Export' and 'Introduction to R') but to no avail. If anyone has any suggestions, I'd be very grateful. Here's the problem: When I enter the command: > guilds <-

Hello Dears. I have a 2 questions about Discriminant Analysis in R. 1- In "ade4" package I perform this analysis for both quantitative and qualitative variables using "discrimin" function. R gives me "Canonical weights/ Loadings" and "Canonical scores" but doesn't give "*F* or *t *or *X-square *statistic" and "P-value" to determine

Hello, Does logistic regression really provide better results than lda or qda ? (my purpose is not classification but highlighting of discriminant variables). If this is true, where could I get an R script performing stepwise logistic regression ? Thanks -- Daniel AMORESE Lab. M2C "Morphodynamique Continentale et C?ti?re" UMR CNRS 6143 Caen/Rouen Centre de G?omorphologie UCBN

Dear R users, I have some environmental variables and I need to find the best combination of them in order to separate two main groups (coded 1 and 2). I have performed a discriminant analysis using the stepclass function as a method for selecting the most relevant environmental variables. The problem is that this function includes a parameter (start.vars) and my results change a lot when I

Dear List: I have the following simple program: x<- sample(site) VarGuilda1<- var(tapply(x,site,func1)) VarGuilda2<- var(tapply(x,site,func2)) VarGuilda3<- var(tapply(x,site,func3)) VarGuilda4<- var(tapply(x,site,func4)) VarGuilda5<- var(tapply(x,site,func5)) VarGuilda6<- var(tapply(x,site,func6)) VarGuilda7<- var(tapply(x,site,func7)) VarGuilda8<-

Hi everyone, I'm trying to solve a problem about how to get the Fisher's discriminant functions of a "lda" (linear discriminant analysis) object, I mean, the object obtained from doing "lda(formula, data)" function of the package MASS in R-project. This object gives me the canonical linear functions (n-1 coefficients matrix of n groups at least), and only with this

Hi, In my data set I have created a matrix of distances. How can I get a list of minimum value in each row? thanks a lot, Rog?rio

Dear All, I am looking at discriminating among several individuals based on a few variable sets (I think some variables do not make sense unless they are entered together, so I "force" them into the models together, hence datasets). I have done so with linear discriminant analysis (LDA) using "MASS::lda", with acceptable results. However, one of my collaborators

Dear Forum, I have a class variable 1 (populations A-E), and two other class variables, variable 2 and variable 3. What I want is to see if the combination of var 2 and var 3, will give me a pattern that allows to distinguish populations. I found several packages like ade4, with pcaiv function and factoMineR. but there are not working. Using the ade4 package, when I try to build the pca: pca1

Dear List, I've around 1000 *.txt files, I've generate with other software. I've now done the following code (below). My question is how can I automate this (with do.call () ?), so it could be done for all the *.txt files. Thanks in advance, Rog??rio names<- list.files() file <- "BLU_Var_%04d.txt" for(i in 1:1000){

Hi, a colleague ran a stepwise discriminant analysis twice in a row and got different results, suggesting some "sochasticity" in the algorithms involved. I looked at her data and found that there was a lot of collinearity, so that I reckoned that maybe "stepclass" (klaR) cannot find a clear winner when trying to include a new variable and makes a random choice. Is that true?

Dears R users, Is there a way to add a column of results to an exported data.frame (exported with write) ? Thanks Rog?rio