In a duplicate pairs event, the result of the conversion of a pair’s absolute score on any board to a ranking score. In the UK, you earn two matchpoints for every pair you beat and one for every pair with the same score. To ‘matchpoint’ is to do this conversion.
Here is an example:
Pair 9, who played N/S against pair 2, achieved a top score. Having beaten all the other 4 N/S scores, they get 8 matchpoints. Pair 7 gets 5 matchpoints; they get 4 matchpoints for beating two scores (the 430 and -50) and 1 matchpoint for tying with pair 10’s 450. Pair 4 scores 2 matchpoints. They beat the -50 but lost to all the other pairs.
You could calculate the E/W scores the same way, though it is easier just to deduct the N/S score from 8 (the top on the board).