similar to: Statistician Needed

Hi, Our discussions about 64 bit R has led me to another thought. I have a nice dual core 3.0 chip inside my Linux Box (Running Fedora 11.) Is there a version of R that would take advantage of BOTH cores?? (Watching my system performance meter now is interesting, Running R will hold a single core at 100% perfectly, but the other core sites idle.) Thanks! -- Noah

Hi, I want to create variable names from within my code, but can't find any documentation for this. An example is probably the best way to illustrate. I am reading data in from a file, doing a bunch of stuff, and want to generate variables with my output. (I could make a "list of lists" and name all the elements, but I really want separate variables.) ################# #This is

Hi, I need a bit of guidance with the sapply function. I've read the help page, but am still a bit unsure how to use it. I have a large data frame with about 100 columns and 30,000 rows. One of the columns is "group" of which there are about 2,000 distinct "groups". I want to normalize (sum to 1) one of my variables per-group. Normally, I would just write a huge

Hi, I use the max function often to find the top value from a matrix or column of a data.frame. Now I'm looking to find the top 2 (or three) values from my data. I know that I could sort the list and then access the first two items, but that seems like the "long way". Is there some way to access "max_2" or similar? Thanks! -- Noah

I'm running a long MCMC chain that is generating samples for 22 variables. I have each run of the chain as a row in a matrix. So: Chain[,1] is the column with all the samples for variable one. Chain[,2] is the column with all the samples for variable 2, etc. I'd like to fit all 22 on a single page to print a nice summary. It is OK if the graphs are small, I just need to show the

Hello, I was just assigned to perform a cost effectiveness study in healthcare. We are studying the cost effectiveness of a proposed diagnostic vs. current screening procedures. One of the team members suggest a commercial software package called "TreeAge Pro". Looking at the description, it appears to be a nice GUI to some very simple models that could be easily constructed in R.

I'm trying to draw an arrow with a curved shaft on the graph as a straight one looks messy on a detailed graph. I've looked in arrows but it doesn't seem to give an option. larrows doesn't look much more promising. I had a look in the archive and couldn't find anything. Any thoughts? Thanks Paul -- View this message in context:

Hi, I have a data.frame that I need to scale. I've been using the scale function and it works nicely. Some of the libraries I'm testing won't accept negative values for data, so I need to find a way to scale the data from 0 to 1 Any ideas? Thans!

Hello, I need to design a fairly simple front-end for someone to use an R script system that I've built. My thought was to just use the text based menus available in the base R package, perhaps in some kind of loop. How have other people done this? Any "best practices" that you can recommend? Thanks! -- Noah Silverman UCLA Department of Statistics 8117 Math Sciences Building

We have two small business that run out of our office. One business has 3 phone lines, and the other has only one. In a perfect world, Asterisk would indicate WHICH line (or group) the outsider caller called, so that we would know which way to answer the phone. The incoming calls would go through a voice mail menu first - different for each company. (Press one for sales, two for

Hi, I'm looking at the "cocktail party" classic problem. I can see how to use ICA to separate the components. But, How do I then create new wav files of the separated sounds so that they can be played? Thanks -- Noah Silverman UCLA Department of Statistics 8208 Math Sciences Building Los Angeles, CA 90095 [[alternative HTML version deleted]]

Hello, I have a time series object (xts) that I iterate over in a loop. Works fine. My challenge is that I want to be able to reference other entries in the series by math. i.e. For today's observation, what were the last 5 observations? If indexed numerically, it is trivial, but I can figure out how to do this with dates. This is slightly more difficult as there may not be an

I have a bunch of data sets that were created for the libsvm tool. They are in "colon separated sparse format". i.e. 1 5:1 27:3 345:10 Is a row with the label of "1" and only has values in columns 5, 27, and 345. I want to read these into a data.frame in R. Is there a simple way to do this? -- Noah Silverman, M.S. UCLA Department of Statistics 8117 Math Sciences

Dean - > if you are having these troubles and everyone keeps advising you to use > asterisk@home why aren't you doing this? Not to be rude, but I believe you are the only one who suggested he use asterisk@home. asterisk@home is a great (actually stupendous) product for those that want to have a PBX with a GUI up and running within a few minutes. It does not, however, force users

Hello, I need to calculate a moving average and an exponentially weighted moving average over a fairly large data set (500K rows). Doing this in a for loop works nicely, but is slow. ewma <- data$col[1] N <- dim(data)[1] for(i in 2:N){ data$ewma <- alpha * data$ewma[i-1] + (1-alpha) * data$value[i] } Since the moving average "accumulates" as we move through the data,

Hello, I'm using the svm function from the e1071 package. It works well and gives me nice results. I'm very curious to see the actual coefficients calculated for each input variable. (Other packages, like RapidMiner, show you this automatically.) I've tried looking at attributes for the model and do see a "coefficients" item, but printing it returns an NULL result.

Hi, I am trying to figure out a "short" way to access two values output from the sort function. >x <- c(3,4,3,6,78,3,1,2) >sort(x, index.return=T) $x [1] 1 2 3 3 3 4 6 78 $ix [1] 7 8 1 3 6 2 4 5 It would be great to do something like this (doesn't work.): c(y, indexes) <- sort(x, index.return=T) But that doesn't work. I CAN grab the output of sort in a

Hi, Next challenge today. I have a script that I call within R: source("foo.R") When it finishes, I get the dreaded output: "There were 50 or more warnings (use warnings() to see the first 50)" So, I type warnings() and get a nice list. (Same error repeatedly, so probably something I'm using in a loop.) The difficult part is I have no idea *where* the warning is

Hi, I've been testing some models with the MCMCpack library. I can run the process and get a nice model "object". I can easily see the summary and even plot it. I can't seem to figure out how to: 1) Access the final coefficients in the model 2) Turn the coefficients into a model so I can then run predictions using them. A summary command will SHOW Me the coefficients, but

Hi, Looking at a large data set with many factors. I would like to expand each factor variable into multiple new variables for each level. (0,1) coding. My first though was just to code a big nasty loop, to take each level and cbind a column onto my data set. But, that seems painful. There must be a better way. Is there an "easy" way to do this in R? (Note, I don't want to