  We have performed Ce $L_3$-edge x-ray absorption spectroscopy (XAS)
measurements on CeO$_{1-x}$F$_x$BiS$_2$, in which the superconductivity of the
BiS$_2$ layer and the ferromagnetism of the CeO$_{1-x}$F$_x$ layer are induced
by the F-doping, in order to investigate the impact of the F-doping on the
local electronic and lattice structures. The Ce $L_3$-edge XAS spectrum of
CeOBiS$_2$ exhibits coexistence of $4f^1$ (Ce$^{3+}$) and $4f^0$ (Ce$^{4+}$)
state transitions revealing Ce mixed valency in this system. The spectral
weight of the $4f^0$ state decreases with the F-doping and completely
disappears for $x>0.4$ where the system shows the superconductivity and the
ferromagnetism. The results suggest that suppression of Ce-S-Bi coupling
channel by the F-doping appears to drive the system from the valence
fluctuation regime to the Kondo-like regime, leading to the coexistence of the
superconducting BiS$_2$ layer and the ferromagnetic CeO$_{1-x}$F$_x$ layer.
