Displaying 20 results from an estimated 4000 matches similar to: "bivariate normal and rho"
2002 May 01
3
bivariate normal cdf and rho
Suppose F(x, y; rho) is the cdf of a bivariate normal distribution, with
standardized marginals and correlation parameter rho. For any fixed x and
y, I wonder if F(x, y; rho) is a monotone increasing function of rho,
i.e., there is a 1 to 1 map from rho to F(x, y; rho).
I explored it using the function pmvnorm in package mvtnorm with
different x and y. The plot suggests the statement may be true.
2011 Dec 10
2
efficiently finding the integrals of a sequence of functions
Hi folks,
I am having a question about efficiently finding the integrals of a list of
functions. To be specific,
here is a simple example showing my question.
Suppose we have a function f defined by
f<-function(x,y,z) c(x,y^2,z^3)
Thus, f is actually corresponding to three uni-dimensional functions
f_1(x)=x, f_2(y)=y^2 and f_3(z)=z^3.
What I am looking for are the integrals of these three
2003 Apr 21
2
piece wise functions
Hello,
Apologies if this question has already arised, hope you can
help me to the find the solution to this or point the place to look at.
I have a multidimensional piece-wise regression linear problem, i.e.
to find not only the regression coefficients for each "interval" but
also the beginning and ends of the intervals.
To simplify it to the one dimensional case and
two intervals,
2008 Jan 23
2
from a normal bivariate distribution to the marginal one
Hello,
I'm quite new with R and so I would like to know if there is a command
to calculate an integral.
In particular I simulated a bivariate normal distribution using these
simple lines:
rbivnorm <- function(n, # sample size
mux, # expected value of x
muy, # expected value of Y
sigmax, # standard deviation of
2012 Apr 19
3
Bivariate normal integral
hello,
I'm trying to improve the speed of my calculation but didn't get to a
satisfying result.
It's about the numerical Integration of a bivariate normal distribution.
The code I'm currently using
x <-
qnorm(seq(.Machine$double.xmin,c(1-2*.Machine$double.eps),by=0.01),
mean=0,sd=1)
rho <- 0.5
integral <- function(rho,x1){
2018 Apr 12
3
Bivariate Normal Distribution Plots
R-Help
I am attempting to create a series of bivariate normal distributions. So using the mvtnorm library I have created the following code ...
# Standard deviations and correlation
sig_x <- 1
sig_y <- 1
rho_xy <- 0.0
# Covariance between X and Y
sig_xy <- rho_xy * sig_x *sig_y
# Covariance matrix
Sigma_xy <- matrix(c(sig_x ^ 2, sig_xy, sig_xy, sig_y ^ 2), nrow = 2, ncol = 2)
2003 Nov 10
1
ts package function filter: mismatch between function action and help (PR#5017)
Dear people,
I'm running
RedHat 9.0
and
R : Version 1.7.1 (2003-06-16)
from the help file
# Usage:
#
# filter(x, filter, method = c("convolution", "recursive"),
# sides = 2, circular = FALSE, init)
# init: for recursive filters only. Specifies the initial values of
# the time series just prior to the start value, in reverse
# time
2010 Oct 20
1
Generate variable with Bivariate Normal Distribution
Dear All
I want to generate variable with Bivariate Normal Distribution by
use mean1 = a, variance1 = b, mean2 = c, variance2 = d, rho = e.
How I can do this.
Many Thanks.
IRD
[[alternative HTML version deleted]]
2011 Oct 19
1
Estimating bivariate normal density with constrains
Dear R-Users
I would like to estimate a constrained bivariate normal density, the
constraint being that the means are of equal magnitude but of opposite
signs. So I need to estimate four parameters:
mu (meanvector (mu,-mu))
sigma_1 and sigma_2 (two sd deviations)
rho (correlation coefficient)
I have looked at several packages, including Gaussian mixture models in
Mclust, but I am not sure
2013 Nov 19
1
Generación de números aleatorios. Mixtura k-puntos
Saludo cordial para cada uno.
Les pido ayuda para generar números aleatorios de una mixtura k-puntos.
Sabemos que la función de distribución F es una mixtura k-puntos si es de
la forma F(x) = p_1 F_1(x) + p_2 F_2(x) + … + p_k F_k(x), donde F_j es una
función de distribución de probabilidad, p_j > 0 y suma(p_j) = 1, para j =
1, 2, …, k.
En mi caso particular F es la suavización de la
2010 Sep 08
11
problem with outer
Hello,
i wrote this function guete and now i want to plot it: but i get this error
message. i hope someone can help me.
Error in dim(robj) <- c(dX, dY) :
dims [product 16] do not match the length of object [1]
p_11=seq(0,0.3,0.1)
p_12=seq(0.1,0.4,0.1)
guete = function(p_11,p_12) {
set.seed(1000)
S_vek=matrix(0,nrow=N,ncol=1)
for(i in 1:N) {
X_0=rmultinom(q-1,size=1,prob=p_0)
2006 Nov 18
1
Questions regarding "integrate" function
Hi there. Thanks for your time in advance.
I am using R 2.2.0 and OS: Windows XP.
My final goal is to calculate 1/2*integral of
(f1(x)^1/2-f2(x)^(1/2))^2dx (Latex codes:
$\frac{1}{2}\int^{{\infty}}_{\infty}
(\sqrt{f_1(x)}-\sqrt{f_2(x)})^2dx $.) where f1(x) and f2(x) are two
marginal densities.
My problem:
I have the following R codes using "adapt" package. Although "adapt"
2006 Nov 17
0
Question regarding "integrate" function
Hi there. Thanks for your time in advance.
My final goal is to calculate 1/2*integral of
(f1(x)^1/2-f2(x)^(1/2))^2dx (Latex codes:
$\frac{1}{2}\int^{{\infty}}_{\infty} (\sqrt{f_1(x)}-\sqrt{f_2(x)})^2dx
$.) where f1(x) and f2(x) are two estimated marginal densities.
My problem:
I have the following R codes using "adapt" package. Although "adapt"
function is mainly designed
2006 Nov 17
0
questions regarding "integrate" function in R
Hi there. Thanks for your time in advance.
My final goal is to calculate 1/2*integral of
(f1(x)^1/2-f2(x)^(1/2))^2dx (Latex codes:
$\frac{1}{2}\int^{{\infty}}_{\infty}
(\sqrt{f_1(x)}-\sqrt{f_2(x)})^2dx $.) where f1(x) and f2(x) are two
marginal densities.
My problem:
I have the following R codes using "adapt" package. Although "adapt"
function is mainly designed for more
2008 Jan 04
0
Bivariate normal equal-probability curve...
Good morning and I appreciate the availability of a help-list. I am a
professional hydrologist, but not a professional statistician. Yet I
find myself using statistical tools at least part of the time. My
discovery of the R-project through a friend has been most helpful.
Here is my problem:
I'm tasked with fitting a dataset comprising correlated discharges
from adjacent watersheds to
2012 Jul 27
3
bivariate normal
Dear list members
I need a function that calculates the bivariate normal distribution for each observation. It is part of a likelihood function and I have 1000's of cases. As I understand it I cannot use packages like "mvtnorm" because it requres a covariance matrix of the same dimension as the number of observations. Basically what I need is a function that takes as arguments a
2004 Jul 10
1
Exact Maximum Likelihood Package
Dear R users,
I am a mathematics postdoc at UC Berkeley. I have written a package
in a Computational Algebra System named Singular
http://www.singular.uni-kl.de
to compute the Maximum Likelihood of a given probability distribution over
several discrete random variables. This package gives exact answers to the
problem. But more importantly, it gives All MLE solutions.
My understanding is that
2002 Nov 12
1
Probabilities for bivariate normal distribution with adapt
Dear R-List:
I`m trying to calculate the probabilities for a bivariate normal
distribution while using the mvtnorm-package(dmvnorm) and the
adapt-package for multidimensional integration.
The problem is that I can`t specify the upper bound in the adapt-package
the way I need it because I don`t need a rectangular area. I want to
calculate the probability starting at the origin under the line y=x.
2011 Aug 25
1
Bivariate normal regression in R
Hello everyone,
I need to fit a bivariate normal regression model to a dataset where the
same covariate (say, X) influences two separate but correlated responses
(say, Y1 and Y2). So, the bivariate
model would look like :
Y1 = a1 + b1*X + e1
Y2 = a2 + b2*X + e2
where e1 and e2 are error terms which can be correlated. Is there any
package in R which can help me fit this model ? Any help will be
2003 Sep 01
0
Re: Plotting bivariate normal distributions.
You'll find that it is a lot easier to do it in R:
# lets first simulate a bivariate normal sample
library(MASS)
bivn <- mvrnorm(1000, mu = c(0, 0), Sigma = matrix(c(1, .5, .5, 1), 2))
# now we do a kernel density estimate
bivn.kde <- kde2d(bivn[,1], bivn[,2], n = 50)
# now plot your results
contour(bivn.kde)
image(bivn.kde)
persp(bivn.kde, phi = 45, theta = 30)
# fancy contour with