Big point index
A very common question we get from our users — what the heck is a big point index?
TL;DR
It is a difference between how player does on big points compared to “normal” points. Every breakpoint and every point from 30–30 on is considered big point.
Long version
Player A wins 65 % of points on his/her serve on normal points. But, wins 72 % of serve points on big points. So first part of big point index is +7 (72–65).
We do the same math for Player A on return. Wins 35 % of normal points when returning, but on big points wins 44 % of return points. And we have second part of big point index, +9 (44–35).
So total big point index for Player A is +16. That’s it ¯\_(ツ)_/¯.
As you can see on the screenshot, in this case BPI goes hand in hand with Shuai Zhang not being able to convert on break points, game points and as a result losing majority of close games (games that go through 30–30 or deuce).
This match was much closer than scoreline suggests.
