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Pearson Points (aka Rule of 15, or Cassino Count) are a hand evaluation method for opening the bidding in 4th seat. When an auction begins Pass-Pass-Pass, the player in 4th position often holds a marginal hand containing 9-12 HCP (high card points), and must decide whether to bid or pass.

Calculating Pearson Points is easy. Add your high card points and the number of spades in your hand. If the total is 15 or more, then you should open the bidding. if the total is 14 or less, then you should pass the hand out.

In my experience, Pearson Points are pretty reliable. They are predicated on the idea that when the honor cards are evenly distributed around the table, the best suit to own is spades because you can outbid the opponents at the 1- or 2-level. Hands short in spades are worth less because of the increased probability of the opponents bidding and landing in their own spade contract.

 KQ987
 AT
 J32
 873

This hand has 10 HCP + 5 spades = 15 Pearson Points. Open the bidding in 4th seat with 1.

 A9
 T987
 AK32
 J43

12 HCP + 2 spades = 14 Pearson Points. Pass.

 Q42
 QJ
 KJ85
 QJ632

12 HCP + 3 spades = 15 Pearson Points. However, rules are made to be broken. I’d pass because the high cards are soft (primarily queens and jacks), and because the short major suits make it likely that the opponents will compete successfully in hearts or spades.

		North
		2
		K75
West		QT973		East
QJ53		AQ97		KT4
J32				A964
A8		South		J54
K643		A9876		852
		QT8
		K62
		JT

West Pass Pass Pass

North Pass 2 (2)

East Pass Pass

South 1 (1) Pass (3)

1. South opens the bidding with 15 Pearson Points.
2. North barely has enough to bid 2.
3. South knows that game is impossible since North is a passed hand.

Pearson Points are named for their American inventor Don Pearson.