Well, don't kill me if I'm wrong but...
i think Emission Spectrum... the color of the light emitted by a star should be the best indicator for how hot it is... the wavelengths of light it emits determines the energy (how hot... like red hot versus white hot)
Absorption Spectrum... not sure...
Doppler Shift tells you if its moving towards or away, and at what speed
Refraction... light is refracted through varying media... it is not a property of a star to the best of my knowledge.
