Displaying 20 results from an estimated 500 matches similar to: "State Space Modelling"
2006 Apr 29
2
[LLVMdev] Register allocation in LLVM
Hello, all,
I want to implement the register allocation algorithm described in the
paper "Register Allocation via Coloring of Chordal Graphs, APLAS'05" in
LLVM. This is a graph coloring algorithm that can find an optimal coloring
of the interference graph in most of the cases. I've downloaded LLVM last
week, and started studying the code. Basically, I have to implement:
1) A
2006 May 01
0
[LLVMdev] Register allocation in LLVM
On Sat, 29 Apr 2006, Fernando Magno Quintao Pereira wrote:
> I want to implement the register allocation algorithm described in the
> paper "Register Allocation via Coloring of Chordal Graphs, APLAS'05" in
> LLVM. This is a graph coloring algorithm that can find an optimal coloring
> of the interference graph in most of the cases. I've downloaded LLVM last
> week,
2005 Dec 01
1
Kalman Smoothing - time-variant parameters (sspir)
Dear R-brains,
I'm rather new to state-space models and would benefit from the extra
confidence in using the excellent package sspir.
In a one-factor model, If I am trying to do a simple regression where
I assume the intercept is constant and the 'Beta' is changing, how do
I do that? How do i Initialize the filter (i.e. what is appropriate to
set m0, and C0 for the example below)?
2001 Sep 14
1
Supply linear constrain to optimizer
Dear R and S users,
I've been working on fitting finite mixture of negative exponential
distributions using maximum likelihood based on the example given in MASS.
So far I had much success in fitting two components. The problem started
when I tried to extend the procedure to fit three components.
More specifically,
likelihood = sum( ln(c1*exp(-x/lambda1)/lambda1 +
c2*exp(-x/lambda2)/lambda2
2007 Nov 15
3
kalman filter estimation
Hi,
Following convention below:
y(t) = Ax(t)+Bu(t)+eps(t) # observation eq
x(t) = Cx(t-1)+Du(t)+eta(t) # state eq
I modified the following routine (which I copied from: http://www.stat.pitt.edu/stoffer/tsa2/Rcode/Kall.R) to accommodate u(t), an exogenous input to the system.
for (i in 2:N){
xp[[i]]=C%*%xf[[i-1]]
Pp[[i]]=C%*%Pf[[i-1]]%*%t(C)+Q
siginv=A[[i]]%*%Pp[[i]]%*%t(A[[i]])+R
2006 Mar 11
1
Non-linear Regression : Error in eval(expr, envir, enclos)
Hi..
i have an expression of the form:
model1<-nls(y~beta1*(x1+(k1*x2)+(k1*k1*x3)+(k2*x4)+(k2*k1*x5)+(k2*k2*x6)+(k3*x7)+(k3*k4*x8)+(k3*k2*x9)+(k3*k3*x10)+ (k4*x11)+(k4*k1*x12)+(k4*k2*x13)+(k4*k3*x14)+(k4*k4*x15)+(k5*x16)+(k5*k1*x17)+(k5*k2*x18)+(k5*k3*x19)+
2009 Sep 11
3
State Space models in R
Hello everybody,
I am writing a review paper about State Space models in R, and I would
like to cover as many packages as I reasonably can.
So far I am familiar with the following tools to deal with SS models:
* StructTS, Kalman* (in stats)
* packages dse[1-2]
* package sspir
* package dlm
I would like to have some input from users who work with SS models:
are there any other packages for SS
2005 Dec 14
1
Kalman Filter Forecast using 'SSPIR'
Dear R Users,
I am new to state-space modeling. I am using SSPIR
package for Kalman Filter. I have a data set containing one dependent
variable and 7 independent variables with 250 data points. I want to use
Kalman Filter for forecast the future values of the dependent variable
using a multiple regression framework. I have used ssm function to
produce the state space (SS)
2008 Jan 24
2
boxplot axis labelling
Hi,
i'm very new to R, so sorry for what i'm sure is a very basic question. I'm
producing a boxplot with the data below:
df3<-data.frame(
x=c(10,11,115,12,13,14,16,17,18,21,22,23,24,26,27,28,29,3,30,32,33,34,35,4,4
1,45,5,50,52,56,58,6,67,6738,68,7,8,9),
fq=c(8,11,1,2,4,4,2,2,6,3,4,2,2,1,1,1,4,51,3,1,1,1,1,35,1,1,19,2,1,1,1,14,1,
1,1,10,13,5),
2006 Apr 29
1
SSPIR problem
I am having a problem with the package SSPIR. The code below
illustrates it. I keep getting the message: "Error in y - f :
non-conformable arrays."
I tried to tweak the code below in many different ways, for example,
substituting rbind for cbind, and sometimes I get a different error
message, but I could not find a variation of this code that would
work.
Any help will be greatly
2004 Oct 04
3
Beginners problem
Hi,
I'm new to R and have a problem with a little test program (see below).
Why doesn't <<- in function rk4
assign the new value to y so that it is seen in rktest. I thought that
<<- does exactly this. But it seems that I
didn't get it right. I would be very appreciative for an explanation of
that behaviour of <<-. I know how to
write the whole thing so that it
2008 Feb 01
2
the "union" of several data frame rows
Hi,
I have a question about how to obtain the union of several data frame
rows. I'm trying to create a common key for several tests composed of
different items. Here is a small scale version of the problem. These
are keys for 4 different tests, not all mutually exclusive:
id q1 q2 q3 q4 q5 q6
1 A C
2 B D
3 A D B
4 C D B D
I would like
2009 Aug 03
3
Help with reshaping data.frame
I'm having trouble reshaping a data.frame from long to wide.
(I think that's the right terminology; feel free to educate me.)
I've looked at the reshape function and package and plyr package,
but I can't quite figure out how to do this after a dozen variations.
I have a data.frame with more levels than this, but similar to:
> tst
K1 K2 K3 V1 V2 V3
1 10 D a 0.08 99
2008 Jul 14
2
long data frame selection error
Hello,
I am trying to select the following headers from a data frame but when I try
and run the command it executes halfway through and give me an error at V188
and V359.
Temp <- data.frame(V4, V5, V6, V7, V8, V9, V10, V11, V12, V13, V14, V15,
V16, V17, V18, V19, V20, V21, V22, V23, V24, V25, V26, V27, V28, V29, V30,
V31, V32, V33, V34, V35, V36, V37, V38, V39, V40, V41, V42, V43, V44, V45,
2006 May 01
1
Problem with optim()
I am having a problem with optim() using the "L-BFGS-B" method. When I
set the lower limit for the third parameter equal to zero I get an
error message:
> low.lim.3 <- 0
> phi_opt <- optim(phi_, model_lik, NULL, method = "L-BFGS-B", lower=c(0.2, -100, low.lim.3, 0), upper= c(10, 100, 10, 10), control = list(maxit = 1000, parscale = c(0.2, u1, 0.002, 0.002), trace =
2012 Apr 12
1
Help with vectorization
Hi every one. I have a exponential function (3 fitting parameters) that I
would like to use to produce data (6 series) without having to use a loop.
Here
wl = seq(300,500,1)
k1 = c(1.2e-6, 4.9e-6, 9.6e-6, 2.7e-10, 6.7e-8, 7.44e-6)
k2 = c(726, 352, 128, 5232, 1538, 128)
k3 = c(-176, -224, -257, 88.7, -111, -256)
stations = c('R5d', 'R5a', 'R9', '108',
2013 Apr 25
2
Vectorized code for generating the Kac (Clement) matrix
Hi,
I am generating large Kac matrices (also known as Clement matrix). This a tridiagonal matrix. I was wondering whether there is a vectorized solution that avoids the `for' loops to the following code:
n <- 1000
Kacmat <- matrix(0, n+1, n+1)
for (i in 1:n) Kacmat[i, i+1] <- n - i + 1
for (i in 2:(n+1)) Kacmat[i, i-1] <- i-1
The above code is fast, but I am curious about
2007 Mar 22
2
dynamic linear models in R
Hi all,
I've just started working my way through Mike West and Jeff Harrison's
_Bayesian Forecasting and Dynamic Models_, and I was wondering if
there were any publically-available packages to handle dynamic linear
models, as they describe.
I found the "dynlm" package, but either I don't yet understand what's
going on or that package uses a different sense of the phrase
2006 Dec 14
3
Model formula question
Hi all,
I'm not familiar with R programming and I'm trying to reproduce a
result from a paper.
Basically, I have a dataset which I would like to model in terms of
successive increments, i.e. (y denote empirical values of y)
y_1 = y1,
y_2 = y1 + delta1,
y_3 = y1 + delta1 + delta2.
...
y_m = y1 + sum_2^m delta j
where delta_j donote successive increments in the y-values, i.e.
delta
2016 Sep 25
3
Variable Progresiva
Hola Comunidad,
Tengo una duda,
Queria que en un For si fuese ejecutando un proceso desde 1 hasta 5 por poner un ejemplo , y que el resultado se fuese guardando en variables que se llamar Ki, es decir k1, k2, k3...
Un ejemplo de como crei que funcionaria y no lo hizo xD
for (i in 1:3) {
paste("k", i, sep = "") <- sum(1:i)
}
Esperaba se crearan las variables k1 =