The pitch effect warps the pitch upwards or downwards depending on the value of the effect (i.e. positive values shift audio higher in pitch, negative values shift audio lower in pitch).
Note: a change of 10 corresponds to one half-step. So to go up a whole octave, you must set the pitch effect to 120, since there are 12 half-steps in an octave. A value of 100 will sound like a minor 7th. Same goes for negative values: to lower a sound by an octave, use a value of -120.
Right now the pitch effect works by changing the speed of the sound, although in the future the ST may change it back to only affecting a sound's pitch.
The pan effect causes the audio to shift towards the left or right output track, depending on the value of the effect (i.e. positive values shift audio to the right, negative values shift audio to the left).