Spades is all about probability

Imagine you’re playing spades. You’re down to three books (or “tricks” as the old folks say). You’re in a tough position because your team need to win two of the remaining books or y’all will be set. On top of that, you’ve been talking shit all game.

Right now your partner has the highest card on the table but you’re not sure if she’s gonna win the book. Do you cut or play over your partner to give your team the better chance of winning the book? Or do you play under with the hope that your partner’s card will hold? If you play spades regularly you’ve no doubt run into this situation. And this is not a trivial decision – the book, the hand, your reputation, and hell, even your relationship with your partner is at stake (and I promise I’m not being dramatic).

So what did you do?

Now there’s no hard and fast rule about the best move in this circumstance. Some folks say “play to win,” but if you play over your partner’s strongest card then you may cost your team a book (and the game). Alternatively, some folks believe you should NEVER play over your partner but this strategy can be problematic as well.

Now back to the question. What did you do?

I’m guessing what you ultimately decided depended on number of factors. What cards have been played?* What cards are left in your hand? What’s the probability that you can win the remaining books with those cards? What cards do you think your partner has left? What cards do your opponents have left? How many sandbags do we have?

If you were confident that you could win the last two books  you might have been more willing to play under. If y’all really needed that book and you thought you could win it, you might have been more willing to play over your partner.

So in short, what you did (whether you knew it or not) involved calculating the probabilities of winning the hand based on the competing strategies.

Like poker, spades is a game that involves the implicit calculation of probabilities. When you think “will that card walk? what’s the chance that this card is going to be cut? who’s cutting? or who has the Joker or Ace of Spades?,” you’re calculating probabilities. Probabilities describe the chance of an event occurring (usually given as a ratio or percentage).

Astute spades players intuitively recognize the probability of a specific card walking can be much different if the card is the first one played versus if it’s the third card played. The chance of a card being cut generally increases as more cards of that suit are played. Identifying who is cutting is more difficult and requires you to watch who is playing what. And if you don’t have the highest card there’s a 1/3rd chance your partner has it and a 2/3rd chance that one of your opponents has it.

Okay so spades involves probabilities. So what?

As you are playing spades you are (or should be) constantly calculating and re-calculating probabilities. I’m not talking hardcore conditional probabilities but rough calculations that you can help you choose the best option. In the forthcoming posts I’ll discuss how you can use knowledge of probabilities to help make you a better spades player.

* If you haven’t kept track please re-evaluate your life as a spades player.

Spades is all about probability