Displaying 20 results from an estimated 3000 matches similar to: "score test for logistic regression"
2007 Aug 31
2
memory.size help
I keep getting the 'memory.size' error message when I run a program I have
been writing. It always it cannot allocate a vector of a certain size. I
believe the error comes in the code fragement below where I have multiple
arrays that could be taking up space. Does anyone know a good way around
this?
w1 <- outer(xk$xk1, data[,x1], function(y,z) abs(z-y))
w2 <- outer(xk$xk2,
2005 Dec 01
2
Minimizing a Function with three Parameters
Hi,
I'm trying to get maximum likelihood estimates of \alpha, \beta_0 and
\beta_1, this can be achieved by solving the following three equations:
n / \alpha + \sum\limits_{i=1}^{n} ln(\psihat(i)) -
\sum\limits_{i=1}^{n} ( ln(x_i + \psihat(i)) ) = 0
\alpha \sum\limits_{i=1}^{n} 1/(psihat(i)) - (\alpha+1)
\sum\limits_{i=1}^{n} ( 1 / (x_i + \psihat(i)) ) = 0
\alpha \sum\limits_{i=1}^{n} (
2007 Aug 28
1
alternate methods to perform a calculation
Consider a data frame (x) with 2 variables, x1 and x2, having equal values.
It looks like:
x1 x2
1 1
2 2
3 3
Now, consider a second data frame (xk):
xk1 xk2
0.5 0.5
1.0 0.5
1.5 0.5
2.0 0.5
0.5 1
1.0 1
1.5 1
2.0 1
0.5 1.5
1.0 1.5
1.5 1.5
2.0 1.5
0.5 2
1.0 2
1.5 2
2.0 2
I have written code to calculate some differences between these
2008 Jul 29
3
finding a faster way to do an iterative computation
useR's,
I am trying trying to find out if there is a faster way to do a certain
computation. I have successfully used FOR loops and the apply function to
do this, but it can take some time to fully compute, but I was wondering if
anyone may know of a different function or way to do this:
> x
[1] 1 2 3 4 5
> xk
[1] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
I want to do:
2007 Jun 15
1
complex contrasts and logistic regression
Hi,
I am doing a retrospective analysis on a cohort from a designed trial,
and I am fitting
the model
fit<-glmD(survived ~ Covariate*Therapy + confounder,myDat,X=TRUE,
Y=TRUE, family=binomial())
My covariate has three levels ("A","B" and "C") and therapy has two
(treated and control), confounder is a continuous variable.
Also patients were randomized to
2012 Nov 16
1
Interpretation of davies.test() in segmented package
My data:
I have raw data points that form a logit style curve as if they were a time
series. Which is to say they form 3 distinct lines with 3 distinct slopes
in backwards z pattern. A certain class of my data looks essentially flat
to the eye with marginal oscillation. What is important to me is the x
value at which the state change is occurring, in other words, the break
point
Use of
2010 Sep 17
1
How to compare, match two columns from diferent dataframe and assign values from one datafram to the other
Dear R experts,
I'm new to R. It seems to be a simple question but I just can't find a way to do it. Please help me.
I have two data sets x and y as shown in the following. I want to compare the first two columns in x and y, find the matched ones and assign the relative value from column 2 of y to generate the third column of x. Any help wil be appreciated. Thanks.
> x
[,1]
2011 May 04
1
hurdle, simulated power
Hi all--
We are planning an intervention study for adolescent alcohol use, and I
am planning to use simulations based on a hurdle model (using the
hurdle() function in package pscl) for sample size estimation.
The simulation code and power code are below -- note that at the moment
the "power" code is just returning the coefficients, as something isn't
working quite right.
The
2008 Sep 12
1
Error in "[<-"(`*tmp*`, i, value = numeric(0)) :
I use "while" loop but it produces an errro. I have no idea about this.
Error in "[<-"(`*tmp*`, i, value = numeric(0)) :
nothing to replace with
The problem description is
The likelihood includes two parameters to be estimated: lambda
(=beta0+beta1*x) and alpha. The algorithm for the estimation is as
following:
1) with alpha=0, estimate lambda (estimate beta0
2008 Aug 22
2
WinBUGS with R
Dear Users,
I am new to both of things, so do not blame me too much...
I am busy with semiparametric regression and use WinBUGS to sample
posteriors.
The code to call Winbugs is as follows:
data <- list("y","X","n","m") #My variables
inits.beta <- rep(0,K)
inits.beta0 <- 0
inits <-
2008 May 05
7
iscsi conn error: Xen related?
Hello all,
I got some severe iscsi connection loss on my dom0 (Gentoo
2.6.20-xen-r6, xen 3.1.1). Happening several times a day.
open-iscsi version is 2.0.865.12. Target iscsi is the open-e DSS product.
Here is a snip of my messages log file:
May 5 16:52:50 ying connection226:0: iscsi: detected conn error (1011)
May 5 16:52:51 ying iscsid: connect failed (111)
May 5 16:52:51 ying iscsid:
2012 Aug 07
6
Decimal number
HI
>i have a little problem please help me to solve it
>this is the code in R:
>> beta0
[1] 64.90614
> beta1
[1] 17.7025
> beta
[1] 17 64
>her beta<- c(beta0, beta1)
thank you in advance
hafida
--
View this message in context: http://r.789695.n4.nabble.com/Decimal-number-tp4639428.html
Sent from the R help mailing list archive at Nabble.com.
2007 Dec 04
1
Metropolis-Hastings within Gibbs coding error
Dear list,
After running for a while, it crashes and gives the following error message: can anybody suggest how to deal with this?
Error in if (ratio0[i] < log(runif(1))) { :
missing value where TRUE/FALSE needed
################### original program ########
p2 <- function (Nsim=1000){
x<- c(0.301,0,-0.301,-0.602,-0.903,-1.208, -1.309,-1.807,-2.108,-2.71) # logdose
2006 Aug 26
1
problems with loop
Dear all,
I am trying to evaluate the optimisation behaviour of a function. Originally
I have optimised a model with real data and got a set of parameters. Now I
am creating simulated data sets based on these estimates. With these
simulations I am estimating the parameters again to see how variable the
estimation is. To this end I have written a loop which should generate a new
simulated data
2012 May 27
7
Customized R Regression Output?
Hello R-Experts,
I am facing the problem that I have to estimate several parameters for a lot
of different dependent variables.
One single regression looks something like this:
y = beta0 + beta1 * x1 + beta2 * x2 + beta3 * x1 * x2 + beta4 * x4 + beta5 *
lag(x4,-1)
where y is the dependent variable and xi are the independent ones. Important
to me are the different estimates of betai and their
2012 Jul 02
1
How to get prediction for a variable in WinBUGS?
Dear all,I am a new user of WinBUGS and need your help. After running the following code, I got parameters of beta0 through beta4 (stats, density), but I don't know how to get the prediction of the last value of h, the variable I set to NA and want to model it using the following code.Does anyone can given me a hint? Any advice would be greatly appreciated.Best
2008 Jan 07
1
Avoiding FOR loops
useR's,
I would like to know if there is a way to avoid using FOR loops to perform
the below calculation.
Consider the following data:
> x
[,1] [,2] [,3]
[1,] 4 11 1
[2,] 1 9 2
[3,] 7 3 3
[4,] 3 6 4
[5,] 6 8 5
> xk
Var1 Var2 Var3
1 -0.25 1.75 0.5
2 0.75 1.75 0.5
3 1.75 1.75 0.5
4 2.75 1.75 0.5
5 3.75 1.75
2012 Dec 04
1
Winbugs from R
Hi,
I am trying to covert a Winbugs code into R code. Here is the winbugs code
model{# model’s likelihoodfor (i in 1:n){time[i] ~ dnorm( mu[i], tau ) # stochastic componenent# link and linear predictormu[i] <- beta0 + beta1 * cases[i] + beta2 * distance[i]}# prior distributionstau ~ dgamma( 0.01, 0.01 )beta0 ~ dnorm( 0.0, 1.0E-4)beta1 ~ dnorm( 0.0, 1.0E-4)beta2 ~ dnorm( 0.0, 1.0E-4)#
2010 Nov 30
1
StructTS with 2 seasons
Dear All,
I am trying to fit a structural time series model using the StructTS
function (package stats) with only 2 seasons (summer and winter). More
than 2 seasons work fine but with 2 seasons I get this error:
> fit <- StructTS(y.ts, type="BSM")
Error in T[cbind(ind + 1L, ind)] <- 1 : subscript out of bounds
I have looked at Prof. Ripley's 2002 RNews article but cannot
2020 Jun 22
2
[PATCH 13/16] mm: support THP migration to device private memory
On Mon, Jun 22, 2020 at 4:02 PM John Hubbard <jhubbard at nvidia.com> wrote:
>
> On 2020-06-22 15:33, Yang Shi wrote:
> > On Mon, Jun 22, 2020 at 3:30 PM Yang Shi <shy828301 at gmail.com> wrote:
> >> On Mon, Jun 22, 2020 at 2:53 PM Zi Yan <ziy at nvidia.com> wrote:
> >>> On 22 Jun 2020, at 17:31, Ralph Campbell wrote:
> >>>> On