Displaying 20 results from an estimated 10000 matches similar to: "Plotting questions"
2013 May 16
2
R looping help
Hey I'm not really sure what I should put on here, but I am having trouble
with my R code. I am trying to get the p-values, R^2s etc for a number of
different groups of variables that are all in one dataset.
This is the code:
#Stand counter
st<-1
#Collections
stands<-numeric(67)
slopes<-numeric(67)
intercepts<-numeric(67)
mses<-numeric(67)
rsquares<-numeric(67)
2006 Mar 01
1
a strange problem with integrate()
Dear all,
I am stuck on the following problem with integrate(). I have been out of
luck using RSiteSearch()..
My function is
g2<-function(b,theta,xi,yi,sigma2){
xi<-cbind(1,xi)
eta<-drop(xi%*%theta)
num<-exp((eta + rep(b,length(eta)))*yi)
den<- 1 + exp(eta + rep(b,length(eta)))
result=(num/den)*exp((-b^2)/sigma2)/sqrt(2*pi*sigma2)
2011 Jan 27
1
Minor typo in influence.measures.Rd ?
Dear list,
There is, I believe, a minor typo in the example section of
influence.measures.Rd. In the final example the word `does` appears
where I suspect `dose` is required:
I couldn't remember exactly what format patches should be in, so here is
one as diff would produce:
Index: devel/src/library/stats/man/influence.measures.Rd
2012 Jul 03
2
EM algorithm to find MLE of coeff in mixed effects model
I have a general question about coefficients estimation of the mixed model.
I simulated a very basic model: Y|b=X*\beta+Z*b +\sigma^2* diag(ni);
b follows
N(0,\psi) #i.e. bivariate normal
where b is the latent variable, Z and X are ni*2 design matrices, sigma is
the error variance,
Y are longitudinal data, i.e. there are ni
2011 Dec 02
1
1.6x speedup for requal() function (in R/src/main/unique.c)
Hi,
FWIW:
/* Taken from R/src/main/unique.c */
static int requal(SEXP x, int i, SEXP y, int j)
{
if (i < 0 || j < 0) return 0;
if (!ISNAN(REAL(x)[i]) && !ISNAN(REAL(y)[j]))
return (REAL(x)[i] == REAL(y)[j]);
else if (R_IsNA(REAL(x)[i]) && R_IsNA(REAL(y)[j])) return 1;
else if (R_IsNaN(REAL(x)[i]) && R_IsNaN(REAL(y)[j])) return 1;
2009 Oct 27
1
Poisson dpois value is too small for double precision thus corrupts loglikelihood
Hi - I have a likelihood function that involves sums of two possions:
L = a*dpois(Xi,theta1)*dpois(Yi,theta2)+b*(1-c)*a*dpois(Xi,theta1+theta3)*dpois(Yi,theta2)
where a,b,c,theta1,theta2,theta3 are parameters to be estimated.
(Xi,Yi) are observations. However, Xi and Yi are usually big (>
20000). This causes dpois to returns 0 depending on values of theta1,
theta2 and theta3.
My first
2010 Apr 27
1
TikzDevice and texi2dvi
Dear All,
I am starting to use the tikzDevice package, but I am experiencing some
(minor problems).
If I try to run the script at the end of the email, I get the following
error
Error in tools::texi2dvi("normal.tex", pdf = T) :
Running 'texi2dvi' on 'normal.tex' failed.
Messages:
sh: /usr/bin/texi2dvi: not found
How do I install the missing texi2dvi?
I found some
2017 Jun 14
3
about fitting a regression line
Hi R users,
I have some data points (Xi, Yi), and they may follow such a pattern Yi =
cCOS(Xi) + d, how to find the c and d in R? which function to use? Also,
how to get the R2 and p value for this correlation? Thanks for any kind of
help.
[[alternative HTML version deleted]]
2007 May 21
1
Boostrap p-value in regression [indirectly related to R]
Hello All,
Despite my preference for reporting confidence intervals, I need to
obtain a p-value for a hypothesis test in the context of regression
using bootstrapping. I have read John Fox's chapter on bootstrapping
regression models and have consulted Efron & Tibshirani's "An
Introduction to the Bootstrap" but I just wanted to ask the experts here
for some feedback to make
2011 Feb 16
2
distance between consecutive points
Dear R users,
I have two coloumns of data, say x and y, referring to a list of
points in 2D space. I am trying to develop a code that will give me
the distances (using Pythagoras) between consecutive points (xi,yi)
and (xi+1,yi+1). So far I have come up with the following:
for (i in 1:length(x)) d<-sqrt((x[i+1]-x[i])^2+(y[i+1]-y[i])^2)
For example, if I use the two points (note, I have
2017 Jun 14
0
about fitting a regression line
Start with the lm() function; i.e., see
?lm
-Don
--
Don MacQueen
Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062
On 6/14/17, 3:40 PM, "R-help on behalf of lily li" <r-help-bounces at r-project.org on behalf of chocold12 at gmail.com> wrote:
Hi R users,
I have some data points (Xi, Yi), and they may follow such a
2009 May 14
2
specify the number of decimal numbers
Hi,
I was wondering how to specify the number of decimal numbers in my
computation using R? I have too many decimal numbers for my result, when I
convert them to string with as.character, the string will be too long.
Thanks and regards!
--
View this message in context: http://www.nabble.com/specify-the-number-of-decimal-numbers-tp23538852p23538852.html
Sent from the R help mailing list archive at
2005 Aug 23
6
priority of operators in the FOR ( ) statement
Dear All,
I spent an entire evening in debugging a small, fairly simple program in R
- without success. It was my Guru in Bayesian Analysis, Thomas Fridtjof,
who was able to diagonose the problem. He said that it took a long time
for him also to locate the problem.
This program illustrates in some ways the shortcomings of the error
messages that R responds with. In this case, it was quite
2009 Mar 27
1
LME as part of meta-analysis
Hi, I'm having a problem using LME and hopefully I can get some help. Here
is what I'm doing:
I have a model like this:
yi = alpha + theta * xi + beta * zi + error, errors are normally distributed
mean 0, var sigma^2
xi and zi are generated from normal distributions within a specified range.
True values of alpha, theta, beta and sigma^2 are chosen with a specific
mean and variane
2007 Jun 14
3
how to fit y=m*x
Hi There,
I have a set of data (xi,yi).I want to fit them with the equation
y=mx.
note: in the above equation, there is no intercept.
I don't know how to use common software such as R , matlab, sas, or
spss to do this kind of regression.
Does anyone know how to do this?
I know it is easy to use least square method to do this by
programming. But I want to find if there exists some common
2010 Dec 14
2
multivariate multi regression
Hello,
I want to model my data with the following model:
Y1=X1*coef1+X2*coef2
Y2=X1*coef2+X2*coef3
Note: coef2 appears in both lines
Xi, Yi is input versus output data respectively
How can I do this in R?
I got this far:
lm(Y1~X1+X2,mydata)
now how do I add the second line of the model including the cross
dependency?
Your help is greatly appreciated!
Cheers, Bastiaan
2017 Jun 14
3
about fitting a regression line
Thanks. I thought lm() function is for linear model, such as the
correlation below:
Y= aX + b
On Wed, Jun 14, 2017 at 5:25 PM, MacQueen, Don <macqueen1 at llnl.gov> wrote:
> Start with the lm() function; i.e., see
>
> ?lm
>
> -Don
>
> --
> Don MacQueen
>
> Lawrence Livermore National Laboratory
> 7000 East Ave., L-627
> Livermore, CA 94550
>
2011 Feb 04
3
uniroot
Hi,
I am using the uniroot function in order to carry out a bivariate Monte
Carlo simulation using the logistics model.
I have defined the function as:
BV.FV <- function(x,y,a,A)
(((x^(-a^-1)+y^(-a^-1))^(a-1))*(y^(a-1/a))*(exp(-((1^(-a^-1)+y^(-a^-1))^a)+y^-1)))-A
and the procedure is as follows:
Randomly generate values of A~(0,1), y0 = -(lnA)^-1
Where: A=Pr{X<xi|Y=yi-1} and a is the
2009 Dec 15
1
Help in R
Hello,
Can anyone give me some suggestion in term of calculating the sum below.
Is there a function in R that can help doing it faster?
x1, x2, ...xn where xi can be 0 or 1. I want to calculate the following:
sum{ beta[a+sum(xi), b+n-sum(xi) ]* [ (1-x1)dnorm(0,1)+x1dnorm(2,1) ]* [
(1-x2)dnorm(0,1)+x2dnorm(2,1) ]* ...* [ (1-xn)dnorm(0,1)+xndnorm(2,1) ] }
The sum in the beginning is over all
2010 Mar 04
2
which coefficients for a gam(mgcv) model equation?
Dear users,
I am trying to show the equation (including coefficients from the model
estimates) for a gam model but do not understand how to.
Slide 7 from one of the authors presentations (gam-theory.pdf URL:
http://people.bath.ac.uk/sw283/mgcv/) shows a general equation
log{E(yi )} = ?+ ?xi + f (zi ) .
What I would like to do is put my model coefficients and present the
equation used. I am an