[MegaDeKay]

Electric cookers don't "measure" pressure. They are thermostatically controlled via a sensor touching the bottom of the bowl and, because they are sealed, that temperature directly translates to the same pressure no matter what altitude you're at.

[defrost]

The temperature at the base of the bowl is close to the temperature of the mass of liquid / solids inside and at the base of the bowl, sure.

I'm less certain the same transfer function always returns the gas pressure at the top of the sealed bowl "no matter what altitude you're at" considering that at the starting point, when first sealed, ambient room atmospheric pressure varies with altitude: for the same initial food mass to be cooked the standardised gas volume included will vary with altitude.

(Alternatively, no matter the altitude, there's always a constant volume to fill with atmospheric gas .. and the mass of that gas will vary with altitude)