Abstract Analog resonances in 178Hf+p have been measured. Strong resonances are observed in the inelastic channels. The displacement energy has been determined accurately and a shift of the order of 100 keV due to deformation is found. The various contributions to the displacement energy of analog states are summarized and a phenomenological formula is given which describes all accurately known displacement energies between A ≈ 88 and A ≈ 209 within their experimental errors of about 25 keV. The determination of displacement energies constitutes a new method of measuring deformation parameters. Deformation parameters for a number of nuclei are calculated and compared to parameters from other experiments.