similar to: graphic representation of a qda object

Hi, I have been using some of the functions in r for classification purposes, chiefly lda, qda, knn and nnet. My problem is that the only one I can figure out how to represenent graphically is lda (using plot.lda). I have tried 'fooling' this function into accepting qda input for plotting but to no avail. I wonder if you have any suggestions? Thanks alot, Anne Marie Power Marine lab.

Hi, I am not sure if I remember correctly a mail last week to this messageboard where Prof Ripley said Fisher's discriminants are not used in lda within R and that Rao's are used instead, is this true? I looked in MASS (1996) but I couldn't find the reference to this in chapter 12 (multivariate analysis), the (help)lda doesn't tell me either. Could anyone tell me where can I

Dear R Help Members, I am aware how to plot the LD1 vs LD2 from a lda in R, using the code: plot(baseline.systat.hat$x, col=baseline.systat.hat$class,pch=as.numeric(baseline.systat.hat$class)) However, I need to use the quadratic discriminant function, qda due to data properties. Is there a way to obtain the same sort of plot for from a qda object (and the output of predict qda). I have not

Hi, What does this mean when I have something like: > qda.boot <- boot(train, qda.bootstrap, R = 500) Error in qda.default(structure(data.matrix(x), class = "matrix"), ...) : Rank deficiency in group M with my qda.bootstrap() looks something like: > qda.bootstrap <- function(data, index) { + boot.qda <- qda(x = data[index, 2:9], group = data[index, 1]) + qda.pred

z <- qda(train, cl) save(z, file = "qda.dat") load("qda.dat") predict(qda.dat, test)$class I'm trying to save z where z <-qda(train, cl) and load z for later use in predict(z, test)$class. I think I successfully saved z by save(z, file = "qda.dat") but when I tried to load by load("qda.dat") and call predict(qda.dat, test)$class, it gives me error

You need to learn how to access code for nonexported methods. See ? "::" > methods(qda) [1] qda.data.frame* qda.default* qda.formula* qda.matrix* see '?methods' for accessing help and source code Shows you that the methods are not exported from the namespace. Hence you need to use the triple colon operator to see their code: > MASS:::qda Once you have the code, I

Dear R user, I'm using qda (quadratic discriminant analysis) function (package MASS) to classify 58 explanatory variables (numeric type with different ranges) using a grouping variable (factor 2 levels "0" "1"). I'm using the qda method for class 'data.frame' (in this way I don't need to specify a formula). Using the function:

I guess the question that is being asked here is what is the scaling matrix that is being returned in the qda object. The help file on qda() says: ... scaling: for each group ?i?, ?scaling[,,i]? is an array which transforms observations so that within-groups covariance matrix is spherical. ... This is a bit ambiguous. I tried a few cases (spectral, QR decomposition, especially given that it is an

Hello, I am Souradeep Chattopadhyay and I am a graduate student at Iowa State University Department of Statistics. Can anyone please explain the mathematical formulation behind the scaling matrix returned by the qda function in MASS package. I want to understand how this scaling matrix is derived from the inputs given to the qda function. Example Code The following example is using

Hi, the following strange error appears when I use qda: > qda1 <- qda(as.data.frame(mfilters[cvtrain,]),as.factor(traingroups)) Error: function is not a closure That's also strange: > qda1 <- qda(mfilters[cvtrain,],as.factor(traingroups)) Error in qda.default(mfilters[cvtrain, ], as.factor(traingroups)) : length of dimnames must match that of dims Some backgroud: >

Dear list, (I've not upgraded to R1.4 yet) I have the following $class component in a predict.qda object: > unique(mod23S.qda.pred$class) [1] 12 17 8 10 4 9 5 13 14 19 20 15 6 3 7 1 23 11 18 21 16 2 22 NA Levels: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Nevertheless, when I try to identify the individual(s) with NA, I get: >

Dear wxruby users I''ve been trying to get wxruby-based weft-qda 0.9.6 running on a linux from scratch 6.1 system (this list had a discussion about weft-qda last year and alex fenton''s also been trying to help me out - no luck so far). I get stuck with wxruby 0.60 (I think). I compiled wxruby against wxGTK 2.4.2 (without gtk2, without unicode - gtk+ version is 1.2.10) - after

Hi all, If I run LDA on the same data (2-class classification) with default(no priors specified in the lda function) vs. "prior=c(0.5, 0.5)", the results are different. The (0.5, 0.5) priors give better 1-classify-to-1 rate, and the proportional priors(default, no priors specified in the lda function) give better 0-classify-to-0 rate, for both training and testing data sets. However,

Hi -- have just followed Christophe''s notes to get Weft QDA up and running on my IBM Thinkpad T20 w/Ubuntu 6.06 (Dapper Drake). Am just going thru the manual and trying various things, as I''m new to qualitative analysis AND new to QDA tools. Anyway, one thing I''ve found is that many (and maybe ALL?) of the CTRL-shortcuts mentioned in the documentation are not working

Hi all! I am Angela, an Italian researcher and I am looking for an application that allows working in team, making a shared codebook, share a text database and code it. I tried AnSWR (the CDC''s QDA application) but its installation is too complicated for students and it is not working on latest version of Windows. What about Weft? Is it possible to share a project or, at least, merge

can you run weft qda on mac with virtual PC? (this is how nvivo and some others work for the mac). us poor mac users...but i commend the open source effort! best, Lisa Lisa Schwartz Language Reading and Culture University of Arizona ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile.

Perhaps, I should complement my previous e-mail question: I am trying to select variables through a quadratic discriminant analysis. It seems to me that a robust criterion is the value of the discriminatory power (i.e. the ratio of the separation of the class means to within-class variance) How can I obtain this ratio from V & R's qda() output ? Thanks (I hope this question is relevant) --

Hi, my name is Leandro and im Argentinian. I plan to build a web CMS on ruby on rails, to provide CAQDAS functionality, and since im building the site in Ruby on Rails and open source, i want to know if Weft QDA engine is open source. If so, id would come in handy to be able to reuse/improve an existing ruby based CAQDAS. I''d like to emphasize the fact that i dont mean to profit from it,

Hi Just released a first version of the WxRuby project I''ve been working on. Firstly, I wanted to say thanks to everyone on this list who''s helped at various points over the past year - every time I ran into a problem someone jumped in with advice. A very brief explanation of the app - I''m a sociologist/anthropologist by trade, and the app is intended for use in

Good Afternoon, I''m new to the mailing list and was wondering if anyone could help me with my current headache. I saw in the previous posts that someone else has had the problem of shifty markings. I too am finding the text immediately above what I wrote appearing in the coding reports, even though the coding in the documents themselves remains as it should. The project involves