Find the quantile function of
$$q=F(x)=[(1-\exp(-bx))^c]*[1+d-d*(1-\exp(-bx))^c]$$ , where $b, c$ are positive real
and $-1<d<1$.
Its answer is
Any help/hint is most welcome.
1 Answer
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Take the term in the first square bracket, call it $z$, then you have a quadratic in $z$. Solve for $z$ then it is easy to solve for $x$. The 2d is in the wrong place in your solution, just a type I guess. Not sure why just one root of the quadratic is used. Also think about what happens when d<0.
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$\begingroup$ thanks your help is much appreciated,and -1<d<1. $\endgroup$ Jun 15, 2014 at 7:40
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$\begingroup$ when d<0 the denominator will mean you are taking the c-th root of a -ve quantity. $\endgroup$ Jun 15, 2014 at 8:29
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$\begingroup$ when i said -1<d<1 , i really meant abs(d)<=1. It was my mistake. $\endgroup$ Jun 15, 2014 at 9:41