Median Expected Score (MXS) combines the two gambling numbers associated with a game – the over/under and point spread – to determine how many points Vegas expects each team to score.
The point spread measures how many points the favorite will beat the underdog by. In other words, F – U = S, where F is the favorite’s score, U is the underdog’s score, and S is the point spread.
The over/under measures the combined number of points scored by both teams. In other words, F + U = O.
With these two formulae, it is possible to solve for F and U:
F = S + U
S + U + U = O
S + 2U = O
2U = O – S
The favorite’s MXS can then be calculated as in the first line above.
I list only the MXS and not either betting line on their own, but the over/under and point spread can be extricated from the MXS rather easily.