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Jourdan’s Probability Tables


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Once you install CDF Player, you'll be able to explore interactive documents in your web browser and learn some of the unyielding facts of bridge life!

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Splits

Probabilities of Splits


Move the slider to change the number of cards in both hidden hands.

The calculator produces the probabilities for available splits. The exact answer is shown as a fraction and the approximate answer is shown as per cent.

For example, 5 cards of a particular suit are out in the two unseen hands. Roughly 4% of such a situations will hazard a 5-0 split.


Shapes

Probabilities of Shapes


Move the slider to show a sublist of ten shapes in order of probability.

For the shapes displayed, the calculator produces the probabilities, which are expressed as per cent.

What are your chances that your longest suit is exactly four cards? Look up the 4-4-4-1, 4-3-3-3, 4-4-3-2 holdings and figure 2.993 + 10.54 + 21.55 to find that happens 35% of the time. What about 5 cards maximum? Happens 44% of the time, which is more often than 4 cards maximum.

What are your chances that your hand is balanced? Look up the 5-3-3-2, 4-3-3-3, 4-4-3-2 holdings and figure 15.52 + 10.54 + 21.55 to find that happens 47.6% of the time. The semi-balanced shapes (7-2-2-2, 6-3-2-2, 5-4-2-2) occur about 16.7% of the chances.

Try a few yourself! What does this mean for your bidding system?


Sides

Probabilities of Sides


Move the slider to change the number of cards held in two hands.

For the sides displayed, the calculator produces the probabilities, which are expressed as per cent.

Notice that a bit over 84% of the time you side will hold at least one 8 or more card fit.

If your side has no 8-card fit or better, you are guaranteed two 7-card fits. Choose one!


High Card Points

Probabilities of HCP


Move the slider to show the probability of high card point (HCP) holdings.

For the HCP holdings displayed, the calculator produces the probabilities, which are expressed as per cent.

How often does that 15–17 HCP holding occur? Just calculate 4.424 + 3.311 + 2.362 to find 10.097% of hands will have 15–17 HCP! Now how many of those are balanced?


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