We present a simple modification of the Rittner polarization model(1) to better represent the dipole moment of a negative ion induced by the electric field of its counterion. At high fields the traditional second-order perturbation theory treatment of ion polarization is not appropriate. The internuclear separation dependence of the induced dipole moment is better described by explicitly modeling the mixing of free ion basis states, The dipole moment function of the ion is evaluated using the ab initio value of the free ion polarizability and its experimentally determined electron affinity, We present a simple and quantitative resolution of the mysterious difference between ab initio polarizabilities and Rittner model-derived values, which previously had been optimized separately for every different counterion.