Memorizing the entire table can be difficult. Neil Kazoross developed a simple way to calculate most of the figures without a lot of memorization, called "Neil's Numbers".
The numbers on top represent the number of points the trailer has to go.
The numbers on bottom represent what each point the leader is leading is worth over 50%.
For example, suppose you are ahead 5-away 8-away.
The trailer has 8 points to go, and Neil's number for 8 is 6 (the number below the 8 in the table).
The difference in the scores is 3. So, multiply 3 * 6 = 18, add to 50%, and you come up with 68%.
If you check Woolsey/Heinrich match equity table, you will see that the equity for being ahead 8-away, 5-away is 68%.
If there is no number in the table, do the appropriate interpolation.
For example, suppose you are ahead 3-0 in a 7 point match.
The trailer has 7 points to go, so each point of lead is worth 6 1/2 points over 50% to you -- thus your equity is about 69 1/2% (my table says 70%).
Suppose you are ahead 8-away 12-away.
There is no number for 12, but it is 1/4 of the way between 11 and 15, and the numbers for these are 5 and 4.
Therefore we can interpolate and use 4 3/4. The difference in the scores is 4, so we multiply 4 * 4 3/4 = 19, add to 50%, and get 69%.
This matches the 8-away 12-away entry in my table.
If you happen to be playing a very long match, the table can be extended.
Neil's numbers are: 19 is 3 1/2, and 25 is 3.
Remembering Neil's numbers is easy. The first four entries are trivial.
After that, all you need to remember is the phrase "8 is 6, 11 is 5, 15 is 4", and you've got it.
For most scores, using Neil's numbers will either match or come within one percent of the entry in the match equity table.
Neil's numbers are incredibly accurate if the leader has 3 or more points to go.
However, if the leader has one or two points to go, Neil's numbers do not give accurate results.
It is recommended that you memorize the equities when the leader has one or two points to go, and use Neil's numbers for other scores.
--Kit Woolsey
