%0 Journal Article %T Common Borel radius of an algebroid function and its derivative %A Nan Wu %A Zuxing Xuan %J Mathematics %D 2009 %I arXiv %X In this article, by comparing the characteristic functions, we prove that for any $\nu$-valued algebroid function $w(z)$ defined in the unit disk with $\limsup_{r\to1-}T(r,w)/\log\frac{1}{1-r}=\infty$ and the hyper order $\rho_2(w)=0$, the distribution of the Borel radius of $w(z)$ and $w'(z)$ is the same. This is the extension of G. Valiron's conjecture for the meromorphic functions defined in $\widehat{\mathbb{C}}$. %U http://arxiv.org/abs/0906.4409v1