Displaying 20 results from an estimated 81 matches for "mu2".
Did you mean:
m32
2012 Oct 05
2
problem with convergence in mle2/optim function
Hello R Help,
I am trying solve an MLE convergence problem: I would like to estimate
four parameters, p1, p2, mu1, mu2, which relate to the probabilities,
P1, P2, P3, of a multinomial (trinomial) distribution. I am using the
mle2() function and feeding it a time series dataset composed of four
columns: time point, number of successes in category 1, number of
successes in category 2, and number of success in ca...
2012 Sep 27
0
problems with mle2 convergence and with writing gradient function
Dear R help,
I am trying solve an MLE convergence problem: I would like to estimate
four parameters, p1, p2, mu1, mu2, which relate to the probabilities,
P1, P2, P3, of a multinomial (trinomial) distribution. I am using the
mle2() function and feeding it a time series dataset composed of four
columns: time point, number of successes in category 1, number of
successes in category 2, and number of success in ca...
2012 Oct 11
2
model selection with spg and AIC (or, convert list to fitted model object)
...0L, 0L, 0L, 0L,
0L)), .Names = c("tv",
"n1", "n2", "n3"), row.names = c(NA, -20L), class =
"data.frame")
# Negative log likelihood functions
NLL1 <- function(par, y){
p1 <- par[1]
p2 <- par[2]
mu1 <- par[3]
mu2 <- par[4]
n1 <- y$n1
n2 <- y$n2
n3 <- y$n3
t <- y$tv
P1 <- (p1*((-1 + exp(sqrt((mu1 + mu2 + p1 + p2)^2 -
4*(mu2*p1 + mu1*(mu2 + p2)))*t))*((-mu2)*(mu2 - p1 + p2) +
mu1*(mu2 + 2*p2)) - mu2*sqrt((mu1 + mu2 + p1 + p2)^2 -
4*(mu2*p1 + mu1*(mu2 + p2))) -...
2011 Jan 27
1
Errors in Integrate
Hello,
I have written the function I would like to integrate in two ways:
denfxn <- function(yy,vv,a2,b2,mu2) {
pp <- 1-pnorm(yy/sqrt(vv))
part1 <- pp^(a2-1)
part2 <- (1-pp)^(b2-1)
part3 <- dnorm(yy,mu2,sqrt(vv))
return(part1*part2*part3) }
denfxnorg <- function(yy,vv,a2,b2,mu2) {
pp <- 1-pnorm(yy/sqrt(vv))
pp <- if (pp < .001) .001
else if (pp > ....
2007 Oct 23
1
How to avoid the NaN errors in dnbinom?
...duced
I know from the help files that for dnbinom "Invalid size or prob will
result in return value NaN, with a warning", but I am not able to find a
workaround for this in my code to avoid it. I appreciate the help. Thanks.
Below is the reproducible code:
mixnbinom=function(y,k1,mu1,k2,mu2,prob,eps=
1/100000){
new.parms=c(k1,mu1,k2,mu2,prob)
err=1
iter=1
maxiter=100
hist(y,probability=T,nclass=30,col="lightgrey",main="The EM algorithm")
xvals=seq(min(y),max(y),1)
lines(xvals,prob*dnbinom(xvals,size=k1,mu=mu1)+
(1-prob)*dnbinom(xvals,size=k2,mu=mu2),col="green...
2006 May 21
2
nls & fitting
...6
5 894.4272 130.390552
6 1264.9111 36.727069
7 1788.8544 52.848587
8 2449.4897 25.128742
9 3464.1016 7.531766
10 4472.1360 8.827367
11 6123.7244 6.600603
12 8660.2540 4.083339
I would like to fit N as a function of x according to a function
depending on 9 parameters (A1,A2,A3,mu1,mu2,mu3,myvar1,myvar2,myvar3),
namely
N ~
(log(10)*A1/sqrt(2*pi)/log(myvar1)*exp(-((log(x/mu1))^2)/2/log(myvar1)/log(myvar1))
+log(10)*A2/sqrt(2*pi)/log(myvar2)*exp(-((log(x/mu2))^2)/2/log(myvar2)/log(myvar2))
+log(10)*A3/sqrt(2*pi)/log(myvar3)*exp(-((log(x/mu3))^2)/2/log(myvar3)/log(myvar3)))
(i.e....
2009 Jul 17
6
Solving two nonlinear equations with two knowns
Dear R users,
I have two nonlinear equations, f1(x1,x2)=0 and f2(x1,x2)=0. I try to use optim command by minimize f1^2+f2^2 to find x1 and x2. I found the optimal solution changes when I change initial values. How to solve this?
BTW, I also try to use grid searching. But I have no information on ranges of x1 and x2, respectively.
Any suggestion to solve this question?
Thanks,
Kate
2005 Nov 09
2
About: Error in FUN(X[[1]], ...) : symbol print-name too long
...ogram is to compare means of two independent samples
that results
in Beherens-Fisher posterior and in the model.file of WinBUGS "d2.bug"
there is the following codes:
model
{
for( i in 1 : 30 ) {
x[i] ~ dnorm(mu1,sig1)
}
for( i in 1 : 30 ) {
y[i] ~ dnorm(mu2,sig2)
}
mu1 ~ dnorm(50,1.0E-6)
sig1 ~ dgamma(0.001,0.001)
mu2 ~ dnorm(50,1.0E-6)
sig2 ~ dgamma(0.001,0.001)
lbda <- mu1 - mu2
}
I??m a new user of WinBUGS and if someone detect error in the model codes
too, I??m grateful.
Thanks for help!
Gilberto Matos.
-----...
2013 Feb 01
2
How does this function print, why is n1 which equals 1 printed as 2?
...I have two questions, (i) how is the function printing when there is no code to print and (ii) how is n1 which equals 1 being reported as 2? I suspect there is something fundamental about R that I don't know.
Thank you for the help.
John
library(epicalc)
n.for.2means.js <- function (mu1, mu2, sd1, sd2, ratio = 1, alpha = 0.05, power = 0.8)
{
n1 <- (sd1^2 + sd2^2/ratio) * (qnorm(1 - alpha/2) - qnorm(1 - power))^2/(mu1 - mu2)^2
n1 <- round(n1)
n2 <- ratio * n1
if (length(alpha) == 1) {
alpha1 <- NULL
}
else {
alpha1 <- alpha
}
if (length(power) ==...
2007 Mar 06
2
Estimating parameters of 2 phase Coxian using optim
Hi,
My name is Laura. I'm a PhD student at Queen's University Belfast and have
just started learning R. I was wondering if somebody could help me to see
where I am going wrong in my code for estimating the parameters [mu1, mu2,
lambda1] of a 2-phase Coxian Distribution.
cox2.lik<-function(theta, y){
mu1<-theta[1]
mu2<-theta[2]
lambda1<-theta[3]
p<-Matrix(c(1, 0), nrow=1, ncol=2)
Q<-Matrix(c(-(lambda1 + mu1), 0, lambda1, -mu2), nrow=2, ncol=2)
q<-Matr...
2006 Jun 07
2
help with combination problem
hello:
I have 3 data.frame objects.
First df object:
Of dim (149,31). Columns 2:31 are marked as T1..T14
and N1..N16.
Name T1 T2 N1 T3 N2 N3 N4 T4
mu1 10 10 9 10 9 9 8 10
mu2 11 11 9 11 9 9 9 11
...
muN 12 12 9 11 9 9 8 12
Second df object:
of Dim (50000,31). Columns 2:31 are maked as T1...T14
and N1..N16.
Name T1 T2 N1 T3 N2 N3 N4 T4
J1 2 3 20 2 22 21 29 3
J2 4 1 20...
2009 Mar 30
0
Problem in S4 object displaying from within a Java application using JRI
I am using JRI (Java R Interface) library in order to call R from within my
Java application. But since the "rmu1" and "rmu2" ,see the following code,
are objects of type S4 once i run the application the value of Null will be
returned for both of them. On this regard, i would appreciate it if anyone
can tell me how i am going to display and/ or convert these objects to Java
objects or any other way to get the resul...
2013 Apr 09
0
[R-SIG-Finance] EM algorithm with R manually implemented?
...gt; likelihood of some observations is zero and therefore the log is -Inf.
>
> Where is my mistake?
>
> My code:
>
> # EM algorithm manually
> # dat is the data
>
>
> # initial values
> pi1<-0.5
> pi2<-0.5
> mu1<--0.01
> mu2<-0.01
> sigma1<-0.01
> sigma2<-0.02
> loglik[1]<-0
> loglik[2]<-sum(pi1*(log(pi1)+
> log(dnorm(dat,mu1,sigma1))))+sum(pi2*(log(pi2)+log(dnorm(dat,mu2,sigma2))))
>
>
>
> tau1<-0
> tau2<-0
> k<-1
>
> # loop...
2008 Feb 15
1
Questions about EM algorithm
Dear all:
Assume I have 3 distributions, x1, x2, and x3.
x1 ~ normal(mu1, sd1)
x2 ~ normal(mu2, sd2)
x3 ~ normal(mu3, sd3)
y1 = x1 + x2
y2 = x1 + x3
Now that the data I can observed is only y1 and y2. It is
easy to estimate (mu1+m2), (mu1+mu3), (sd1^2+sd2^2) and
(sd1^2+sd3^2) by EM algorithm since
y1 ~ normal(mu1+mu2, sqrt(sd1^2+sd2^2)) and
y2 ~ normal(mu1+mu3, sqrt(sd1^2+sd3^2))
However,...
2010 Jun 13
1
using latticeExtra plotting confidence intervals
...to have to the
left side of the formula. This is the example code:
library(lattice)
library(latticeExtra)
sample1<-rnorm(100,10,2)
sample2<-rnorm(100,50,3)
sample3<-rnorm(100,20,2)
sample4<-rnorm(100,40,1)
mu1<-mean(sample1)
ci.upper1<-mu1+2*2
ci.lower1<-mu1-2*2
mu2<-mean(sample2)
ci.upper2<-mu2+2*3
ci.lower2<-mu2-2*3
mu3<-mean(sample3)
ci.upper3<-mu3+2*2
ci.lower3<-mu3-2*2
mu4<-mean(sample4)
ci.upper4<-mu4+2*1
ci.lower4<-mu4-2*1
categories<-c("A","B")
mu<-cbind(mu1,mu2,mu3,mu4)
ci.upper<-cb...
2009 Oct 31
1
Help me improving my code
...age
> bpw <- pennw$bp1000
> dur <- pennw$inuidur1
> fw <- factor(wage)
> Ik <- model.matrix(~fw-1)
> I1 <- Ik[,1]
> I2 <- Ik[,2]
> I3 <- Ik[,3]
> I4 <- Ik[,4]
> I5 <- Ik[,5]
> yelmon <- function(theta,x){
+ mu1 <- theta[1]
+ mu2 <- theta[2]
+ mu3 <- theta[3]
+ mu4 <- theta[4]
+ mu5 <- theta[5]
+ beta <- theta[6]
+ logL <-
sum((Ik*log((exp(mu2-(x*beta))/(1+exp(mu2-(x*beta))))-(exp(mu1-(x*beta))/(1+exp(mu1-(x*beta))))))+(Ik*log((exp(mu3-(x*beta))/(1+exp(mu3-(x*beta))))-(exp(mu2-(x*beta))/(1+exp(mu2-(x*...
2010 Mar 20
2
EM algorithm in R
Please help me in writing the R code for this problem. I've been solving this
for 4 days. It was hard for me to solve it. It's a simulation problem in R.
The problem is
My true model is a normal mixture which is given as
0.5 N(-0.8,1) + 0.5 N(0.8,1). This model has two components.
I will get a random sample of size 100 from this model. I will do this 300
times.
That means, I will have
2009 May 22
0
EM algorithm mixture of multivariate
...ha0*f1+(1-alpha0)*f2
scatterplot3d(y[,1], y[,2], p , highlight.3d=TRUE, col.axis="blue",
col.grid="lightblue",main="val iniz mistura normali multivariata",
angle=120, pch=20)
#verosimiglianza iniziale
l0<-sum(log(p))
l1<-l0
alpha<-alpha0
mu1<-mu01
mu2<-mu02
sd1<-sd01
sd2<-sd02
for (iter in 1:itermax)
{
#passo E
for (i in 1:n) {
tau[i,1]<-(alpha*f1[i])/p[i]
tau[i,2]<-((1-alpha)*f2[i])/p[i]
}
#passo M
alpha= mean(tau[,1])
mu1=colSums(tau[,1]*y)/sum(tau[,1])
mu2=colSums(tau[,2]*y)/sum(tau[,2])
ycen1<-(y-mu1)
ycen2<-(y-m...
2008 Apr 05
2
How to improve the "OPTIM" results
...11764954, 5.92662106, 1.03932953,
-6.21987657,
-0.54763352, 0.20263192) # data
theta0= c(log(2),0,c(0,-.3,.3),log(c(10,.05,.05))) # initial value(In fact,
true parameter value)
n = length(x)
fr2 = function(theta)
{
a1 = theta[1]; a2 = theta[2]
mu1 = theta[3]; mu2 = theta[4]; mu3 = theta[5]
g1 = theta[6]; g2 = theta[7]; g3 = theta[8]
w1=exp(a1)/(1+exp(a1)+exp(a2))
w2=exp(a2)/(1+exp(a1)+exp(a2))
w3=1-w1-w2
obj =((w1^2)/(2*sqrt(exp(g1)*pi))
+ (w2^2)/(2*sqrt(exp(g2)*pi))
+ (w3^2)/(2*sqrt(exp(g2)*pi))
+ 2*w1*w2*dnorm((mu1-mu2)/sq...
2008 Apr 05
2
How to improve the "OPTIM" results
...11764954, 5.92662106, 1.03932953,
-6.21987657,
-0.54763352, 0.20263192) # data
theta0= c(log(2),0,c(0,-.3,.3),log(c(10,.05,.05))) # initial value(In fact,
true parameter value)
n = length(x)
fr2 = function(theta)
{
a1 = theta[1]; a2 = theta[2]
mu1 = theta[3]; mu2 = theta[4]; mu3 = theta[5]
g1 = theta[6]; g2 = theta[7]; g3 = theta[8]
w1=exp(a1)/(1+exp(a1)+exp(a2))
w2=exp(a2)/(1+exp(a1)+exp(a2))
w3=1-w1-w2
obj =((w1^2)/(2*sqrt(exp(g1)*pi))
+ (w2^2)/(2*sqrt(exp(g2)*pi))
+ (w3^2)/(2*sqrt(exp(g2)*pi))
+ 2*w1*w2*dnorm((mu1-mu2)/sq...