search for: q_y

Displaying 9 results from an estimated 9 matches for "q_y".

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2006 May 08
2
On the speed of apply and alternatives?
Dear all, I have to handle a large matrix (1000 x 10001) where in the last column i have a value that all the preceding values in the same row has to be compared to. I have made the following code : # generate a (1000 x 10001) matrix, testm # generate statistics matrix 1000 x 4: qnt <- c(0.01, 0.05) cmp_fun <- function(x) { LAST <- length(x) smpls <- x[1:(LAST-1)] real
2001 Feb 15
2
deviance vs entropy
Hello, The question looks like simple. It's probably even stupid. But I spent several hours searching Internet, downloaded tons of papers, where deviance is mentioned and... And haven't found an answer. Well, it is clear for me the using of entropy when I split some node of a classification tree. The sense is clear, because entropy is an old good measure of how uniform is distribution.
2005 Aug 14
1
complex expression with plotmath
Hello everyone, I want to define a function that receives the name of two variables (may include Greek letters and subscripts) and uses them into the title of a plot. My best attempt is the following: myplot <- function(var1, var2) { v=paste(var1,"==1 & ",var2,"==2"); plot(1:10, main=parse(,,v)) } But when I call it with something like myplot("Q[i]",
2011 Nov 19
1
wald test: compare quantile regression estimators from different samples
...cted conditional on a specific characteristic and I would like to test whether such characteristic indeed affect the estimators. The problem in the test anova.rq is that the response variable should be the same, therefore I cannot use different samples. Consider as an example the following: Model 1:Q_y(tau|X,I=2) = X'beta(tau|I=2) Model2;Q_y(tau|X,I=3) = X'beta(tau|I=3) The first sample consider I=2 and the second I=3. I would like to test whether, at the quantile "tau", beta(tau|I=2) = beta(tau|I=3). I have already tried to design a Wald test like: W <- ((beta(tau|I=2)-beta(...
2007 Apr 24
1
Matrix: how to re-use the symbolic Cholesky factorization?
I have been playing around with sparse matrices in the Matrix package, in particularly with the Cholesky factorization of matrices of class dsCMatrix. And BTW, what a fantastic package. My problem is that I have to carry out repeated Cholesky factorization of a spares symmetric matrices, say Q_1, Q_2, ...,Q_n, where the Q's have the same non-zero pattern. I know in this case one does
2004 Feb 03
1
Stereo mode settings
Hi everyone, I'd like a bit of information about the stereo mode settings in psych_44.h of libvorbis. Specifically, about the adj_stereo structure: typedef struct { int pre[PACKETBLOBS]; int post[PACKETBLOBS]; float kHz[PACKETBLOBS]; float lowpasskHz[PACKETBLOBS]; } adj_stereo; What I am attempting to do is bring lossless stereo coupling down to the lower quality levels in
2018 Feb 02
1
R-gui sessions end when executing C-code
Hi I'm trying to develop some C code to find the fixpoint of a contraction mapping, the code compiles and gives the right results when executed in R. However R-gui session is frequently terminated. I'm suspecting some access violation error due to the exception code 0xc0000005 In the error report windows 10 gives me. It is the first time I'm writing any C-code so I'm guessing I
2006 Dec 02
2
nonlinear quantile regression
Hello, I?m with a problem in using nonlinear quantile regression, the function nlrq. I want to do a quantile regression o nonlinear function in the form a*log(x)-b, the coefficients ?a? and ?b? is my objective. I try to use the command: funx <- function(x,a,b){ res <- a*log(x)-b res } Dat.nlrq <- nlrq(y ~ funx(x, a, b), data=Dat, tau=0.25, trace=TRUE) But a can?t solve de problem,
2007 Apr 14
6
[LLVMdev] Regalloc Refactoring
On Thu, 12 Apr 2007, Fernando Magno Quintao Pereira wrote: >> I'm definitely interested in improving coalescing and it sounds like >> this would fall under that work. Do you have references to papers >> that talk about the various algorithms? > > Some suggestions: > > @InProceedings{Budimlic02, > AUTHOR = {Zoran Budimlic and Keith D. Cooper and Timothy