search for: anaylsis

Hi, I have developed a logistic regression model in the form of (factor_1~ numeric + factor_2) and would like to perform a cross-validation or some similar form of sensitivity analysis on this model. using cv.glm() from the boot package: # dataframe from which model was built in 'z' # model is called 'm_geo.lrm' # as suggested in the man page for a binomial model: cost <-

I'm looking for someone to explain the difference between these procedures. The function prcomp() does principal components anaylsis, and the function cmdscale() does classical multi-dimensional scaling (also called principal coordinates analysis). My confusion stems from the fact that they give very similar results: my.d <- matrix(rnorm(50), ncol=5) rownames(my.d) <- paste("c", 1:10, sep="") # prcomp...

...owever I can't make them plot in the 11:20 slot. I have read all the help files for plot, dotchart etc and can't figure it out. I am after an elegant solution as I have many hundreds of data files that I will need to do this for and I have been creating all my other graphs and doing other anaylsis using a loop and all the files have varying numbers of events to be plotted. Any help would be greatly appreciated. Regards Surrey Jackson

Anyone have a good R tutorial for time series? Or know of a good book? Any advice would be helpful. I've been using matlab and programming things directly (not using canned functions), but now I'm having difficulty figuring out how to say, do freq domain anaylsis and get a CI on my periodogram, or plotting the coherence, etc. Or how to change certain parameters, e.g. fit AR(p) with p determined by BIC not AIC. Also, I'm a little uncertain as to what formula certain functions are using. A tutorial (or any suggestions) would be great as the refman is n...

...ing the call if it continued. Here are some sanitized Perl based AGI excerpts that accomplish this: sub callfwd_loop_check { my %v; ($v{callednum},$v{cfnum}) = @_; $v{num} = $AGI->get_variable($v{cfnum}); if ($v{num}) { debug(" Call Loop Anaylsis for ".$v{callednum}." = LOOPING"); return(1); } else { debug(" Call Loop Anaylsis for ".$v{callednum}." = NO LOOP"); $AGI->exec('Set',"__".$v{cfnum}."=".$v{callednum...

...range. True values of alpha, theta, beta and sigma^2 are chosen with a specific mean and variane tau^2. I have a function which generates the yi from the other variables, then a function that does a linear regression using lm to create the estimates. I then want to use this data to do a meta-anaylsis with the above repeated between 10-20 times. Within this, I want to use lme to create estimates for the average true value, sample mean and average standard error for alpha, theta, beta and the respective tau^2 values for each of these. For the lme part, I'm using this a<-summary(lme(alp~...

...measured each of 37 variables. I want to find those variables that best discriminate between the two groups, and I want to visualise that and create a classification function. Please note at this stage it is a proof of concept problem - I realise that I must follow this up with a much more robust anaylsis involving cross-validation. 1) First problem, I got this error message: > z <- lda(C0GRP_NA ~ ., dpi30) Warning message: variables are collinear in: lda.default(x, grouping, ...) I guess this is not a good thing, however, I *did* get a result and it discriminated perfectly between my grou...

hello, I am using the ROC package to evaluate predictive models I have successfully plot the ROC curve, however ?is there anyway to obtain the value of operating point=optimal threshold value (i.e. the nearest point of the curve to the top-left corner of the axes)? thank you very much, jose daniel anadon area de ecologia universidad miguel hernandez espa?a

Atheros support is not ''built in'' for 3.4, so I need some pointers on adding it. Is it in 4.0? It is in the current Novell Linux desktop professional (we used that on a system the other week). The reason for Atheros support, is that all the network anaylsis tools work well with it (and I have one!).

Is anybody interested in cleanly separating encode and decode in vorbis? I'm trying to take a stab at it myself from the head of cvs as of this morning, but it looks like a lot of files contain both encode-only and decode-only functions. An obvious one is mdct.c, which contains mdct_forward and mdct_backward (which isn't that big of a deal, since both are pretty well-contained, but it

The virtio_net driver never sends the multicast address list to the host. This is because send command takes a pointer to scatter list to send but only inserts that one entry into the outgoing scatter list. This bug has been there since: commit f565a7c259d71cc186753653d978c646d2354b36 Author: Alex Williamson <alex.williamson at hp.com> Date: Wed Feb 4 09:02:45 2009 +0000 virtio_net:

The virtio_net driver never sends the multicast address list to the host. This is because send command takes a pointer to scatter list to send but only inserts that one entry into the outgoing scatter list. This bug has been there since: commit f565a7c259d71cc186753653d978c646d2354b36 Author: Alex Williamson <alex.williamson at hp.com> Date: Wed Feb 4 09:02:45 2009 +0000 virtio_net: