can't find the right way to to input the result?

Asked Feb 17 '15 at 03:32

Active Feb 17 '15 at 04:13

Viewed 53 times

In the following program I can't find the right way to get the answer. I mean, can't find the right parameter value:

f.sigma <- function(sigma, x)
{
 n <- length(x)
 sum1 <- sum(x^2)
 sum2 <- sum(log(1-exp(-1*(x/sigma)^2)))
 sum3 <- sum(x^2/(exp((x/sigma)^2)-1))

 ans <- -1*n + sum1/sigma^2 + (n/sum2+1)/sigma^2*sum3
 return(ans)
}

burrx.mle1 <- function(x, lower, upper)
{
 n <- length(x)
sigma.root <- uniroot(f.sigma, interval=c(lower,upper), x=x)
sigmahat <- **sigma.root$root**
thetahat <- -1*n/sum(log(1-exp(-1*(x/sigmahat)^2)))
ans <- list(theta.hat=thetahat, sigma.hat=sigmahat)
 return(ans)
}
burrx.mle1(c(4,1,5),1,5)

another thing what does it mean my sigma.root$root? basically what is the use of $root? here in burrx.mle1(c(4,1,5),1,5) what does it mean my c(4,1,5)?

edited Feb 17 '15 at 04:13

asked Feb 17 '15 at 03:32

anova

2

Please read this : http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example – Metrics Feb 17 '15 at 03:42
For your second question: check out `?uniroot` where the `Value` paragraph is: `A list with at least four components...`. So `uniroot` returns a list, and you can access the `root` element by using `uniroot(...)$root`. – Peter Diakumis Feb 17 '15 at 04:12
... for your edit: it's the same as this: `burrx.mle1(x = c(4, 1, 5), lower = 1, upper = 5)`. – Peter Diakumis Feb 17 '15 at 04:17
but what does it mean by c(4,1,5)? – anova Feb 17 '15 at 04:18
1

I think you need to start reading a bit more about R. `c(1, 2, 3)` is a vector. – Peter Diakumis Feb 17 '15 at 04:19

can't find the right way to to input the result?

0 Answers0